FAMILY: MALVACEAE ORIGIN: BRAZIL
ABUTILON IS CALLED FLOWERING MAPLE because of the shape of its broad, five-lobed leaves, but it is in no way a maple. It is more closely related to the hollyhock and to the weed known as velvet leaf. When given good light and proper care, abutilon rewards its keeper by producing papery blossoms on drooping stems nearly year-round. Flowers may be red, yellow, pink, orange, or peach, depending on variety. Some varieties feature leaves mottled with yellow, but the strongest growers have solid green leaves. Abutilon plants tend toward legginess, so it is important to prune them back by one-third their size in the spring, just before the most vigorous flush of new growth begins. Also pinch back stems occasionally through the summer to promote a full, bushy shape. Regular pruning makes it easy to keep an abutilon less than 18 in/45 cm high and wide. If you want an upright plant to 36 in/1 m tall, tie long branches to sturdy stakes.
Flowering maple (Abutilon)
Light: Bright indirect light from a south or west window.
Temperature: Average room temperatures (65–75°F/18–24°C) year-round.
Fertilizer: From spring through fall, feed every 2 weeks with a balanced houseplant fertilizer. In winter, feed monthly, as plants grow more slowly.
Water: Water thoroughly and then allow plants to dry until the top inch of soil feels dry to the touch before watering again. Mist every few days in winter to prevent problems with spider mites when the air is very dry.
Soil: Any peaty potting soil; never add lime, as abutilon likes acidic soil conditions.
Repotting: Repot young plants every 6 months or so to accommodate growing roots. After plants fill an 8 in/20 cm pot, usually when they are 3 years old, propagate new plants from stem tip cuttings and discard the parent plant.
Longevity: Plants become woody and unattractive by the time they are 3 or 4 years old, but can be kept indefinitely by propagating stem tip cuttings.
Propagation: Take 4 in/10 cm-long stem tip cuttings in spring or summer and set them to root in damp seed-starting mix as described on page 299. Use rooting powder. Transplant to potting soil after 4 to 6 weeks, setting three rooted cuttings in a 6 in/15 cm container.
Selections: Abutilon has been extensively hybridized, so there are dozens of named cultivars. Those with mottled or variegated foliage are best grown as foliage plants, because they tend to be weak bloomers.
Display tips: In addition to being grown in pots or hanging baskets, abutilon can be trained to assume a treelike shape by tying the main stem to a sturdy stake and pinching off all branches that emerge from the lowest 15 in/38 cm of stem.
Plant does not bloom.
CAUSE: Not enough light, or needs additional fertilizer.
REMEDY: Move plant to a place where it will get bright natural light half the day. Switch to a high-phosphorous fertilizer. Some plants bloom very little in winter, but vigorous hybrids should bloom year-round with good light and regular feeding.
Flowers and low leaves drop.
CAUSE: Uneven watering, resulting in some roots remaining dry; too much direct sun.
REMEDY: Rehydrate pot as described on page 328. In summer, move plant to a place where it will be protected from hot midday and afternoon sun.
Sticky leaves; small insects present on leaves.
CAUSE: Aphids.
REMEDY: Prune plant to remove badly infested leaves. Clean thoroughly with plenty of water every 3 days for 2 weeks. See page 269 for more information on controlling this pest.
Leaves are pale and stippled with yellow dots; faint webbing on leaf undersides.
CAUSE: Spider mites.
REMEDY: Isolate plant, and prune off and dispose of badly infested leaves. Clean undersides of remaining leaves with warm, soapy water. Mist daily for a week and see if plant shows signs of recovery. If plant has a stem that is not infested, attempt to propagate its tip, because seriously damaged plants may not be worth saving.
FAMILY: ARACEAE ORIGIN: CENTRAL AND SOUTH AMERICA
THE COLORFUL, WAXY, HEART-SHAPED SPATHES of anthurium, which are often seen in cut-flower arrangements, are the reward for growing this tropical plant. Older anthuriums were temperamental, but advances in breeding in the last few decades have resulted in plants that are much more lush, compact, and willing to flower. Blooms, which are really bracts, last for up to 8 weeks, and many vigorous hybrids bloom nearly year-round, taking a brief break in winter. Very compact plants grow to only 12 in/30 cm tall, but larger ones may grow to 18 in/45 cm tall and wide. Flower colors include white, orange, and pink.
Flamingo flower (Anthurium hybrid)
Do provide ample humidity by keeping your anthurium on a tray filled with damp pebbles or in a room with a humidifier. To keep leaves glossy and free of pests, wipe leaves clean from time to time with a damp cloth or clean plant with a fine spray of warm water. Do not allow pets to chew on anthurium foliage, as it contains calcium oxalate crystals and several toxic proteins that can cause severe mouth burning or skin irritation in all mammals, including humans.
Light: Bright to moderate, with no direct sun.
Temperature: Average to warm (65–80°F/18–27°C). Plant grows best when there is little difference between daytime and nighttime temperatures.
Fertilizer: From spring through late summer, feed plants monthly with a high-phosphorus plant food. In fall and winter, feed every 6 weeks with a balanced fertilizer. Newly purchased plants often have time-release fertilizer in the pot and need no feeding until plant is repotted.
Water: In spring and summer, water frequently to keep soil lightly moist. Leach pots once or twice in summer as described on page 263. In fall and winter, water less, but do not allow soil to dry out. Maintain moderate to high humidity.
Soil: A peaty potting soil, such as African violet mix.
Repotting: Repot annually in spring, shifting plant to a slightly larger pot. Set plant high, so the crown sits just above the soil line. If roots show at the surface between repottings, cover them with moss or a light sprinkling of potting soil.
Longevity: 5 years or more; indefinitely when propagated by division.
Propagation: When plant produces a new crown more than an inch away from the main one, gently pull it away when repotting plant and set it in a small container. With good care, it should begin blooming after about a year.
Selections: Look for named varieties, many of which will have trademarks on the plant tags. These are hybrids bred for compact growth and heavy flowering.
Display tips: Keep plant in a handsome ceramic pot that coordinates well with the color of the blooms. Snip out central flower to prolong the life of the colorful spathes and to avoid pollen on tabletops.
Plant does not bloom.
CAUSE: Young age; too little light; too much nitrogen fertilizer.
REMEDY: Plants do not bloom until they are about 1 year old. To promote bud formation, move plant to a bright place, such as filtered light from a south or west window. After buds open, move plant to lower light. Check the fertilizer analysis to make sure the second number (phosphorous) is higher than the first one (nitrogen).
Leaves turn yellow.
CAUSE: Overwatering.
REMEDY: Check drainage holes to make sure they are not plugged by debris. Water less, and consider repotting plant using a peaty soil mix that includes perlite. Anthuriums need a little air around their roots.
Lower leaves are yellow with brown tips.
CAUSE: Overfertilization.
REMEDY: Leach pot as described on page 263. Resume feeding after a month, mixing fertilizer at half the normal strength. Brown leaf tips without yellowing may be a sign of extremely dry air. In this case, increase humidity.
Small insects flit about at soil’s surface.
CAUSE: Fungus gnats.
REMEDY: Allow surface to dry between waterings. See page 270 for other control measures for this pest.
FAMILY: ACANTHACEAE ORIGIN: BRAZIL
APHELANDRA’S GLOSSY GREEN LEAVES marked with bold white leaf veins are reason enough to grow this plant, which matures into a 4-foot-tall, evergreen shrub in its tropical homeland of Brazil. Potted plants usually grow to no more than 15 in/38 cm tall and are best kept in pots no larger than 6 in/15 cm in diameter. Most people obtain a blooming aphelandra, which shows a lovely cluster of yellow bracts from which emerge delicate, yellow, tubular flowers. The flowers last only a few days, but the bracts often persist for 4 to 8 weeks. After the bracts deteriorate, clip them off and allow the plant to rest in a cool room for about 2 months. As light becomes more abundant in late spring, move plant to a bright place near a south or west window, but not in direct sunlight. Or, shift it to a shady porch or patio. When exposed to bright light for 3 months, aphelandra will usually rebloom in the fall, its natural bloom season. Light intensity rather than day length triggers flowering. A zebra plant may not bloom when kept in low light, but it will earn its place with its exotic foliage.
Zebra plant (Aphelandra squarrosa)
Light: In spring and summer, bright. In fall and winter, moderate.
Temperature: Warm (65–80°F/18–27°C).
Fertilizer: From spring through fall, feed every 2 weeks. Leach pots twice during the summer (see page 263). In winter, feed only every 6 weeks.
Water: Keep soil constantly moist. Do not let this plant dry out. Maintain moderate to high humidity.
Soil: Potting soil amended with peat moss or African violet mix.
Repotting: Annually in spring to refresh soil. Keep plants slightly rootbound.
Longevity: 1 to several years; indefinitely if propagated from rooted cuttings.
Propagation: Take stem tip cuttings in spring and root as described on page 299. Use rooting powder to speed rooting.
Selections: The most common cultivar, ‘Dania’, has emerald green leaves with white veins. The white venation is more dramatic in ‘Apollo’. ‘Red Apollo’ features stems and leaf undersides blushed with red.
Display tips: Wipe leaves often with a damp cloth to keep them glossy. Display in a prominent place in fall, when the plant is in bloom.
Leaves become crinkled or curled.
CAUSE: Too much light.
REMEDY: Move plant to a shadier location.
Growing tips wilt.
CAUSE: Soil too dry.
REMEDY: Aphelandra requires constant moisture, which can be a challenge in summer when the plant is kept in bright light. Rehydrate pots that may have dried out in the center (see page 328). This often happens with rootbound plants grown in a peaty potting mix.
Lowest leaves wilt and drop off.
CAUSE: Too dry; too wet; excessive fertilizer.
REMEDY: Maintain constant moisture and reduce strength of fertilizer solution. Leach pots to remove possible accumulated salts (see page 263).
Small yellow spots on leaves; tiny flying insects are present.
CAUSE: Whitefly.
REMEDY: Isolate plant and install sticky traps as described on page 278.
Plant is weak; grows slowly; small flying insects present.
CAUSE: Fungus gnats.
REMEDY: The moist, peaty soil aphelandra prefers is attractive to this irritating pest. Keep soil slightly dry for several days, then trap larvae with potato pieces as described on page 271.
White cottony masses on stems.
CAUSE: Mealybug.
REMEDY: Remove mealybugs with a cotton swab dipped in alcohol or vegetable oil. Follow other control measures described on page 273.
Small sucking insects on leaf undersides and new leaves.
CAUSE: Aphids.
REMEDY: Clean plant thoroughly with water, then spray with insecticidal soap. See other control measures on page 269.
NAMED AFTER SEVENTEENTH-CENTURY, French-born plantsman Michel Begon, the begonia family includes more than 900 species, and there are ten times that many named hybrids. Most begonias grown as houseplants come from tropical regions, so they are warm-natured plants. All begonias have fleshy stems and lopsided leaves, with half of the leaf larger than the other half. Leaves vary in shape from elongated hearts to pointed, ivylike forms, and some begonias have rounded leaves with scalloped edges. Begonia flowers are either male or female. The male flowers tend to be short lived, while the female flowers persist for weeks as enclosures for winged seedpods.
Angel-wing begonia (Begonia × corallina)
Numerous “outdoor” begonias can be grown indoors for short periods, including the wax begonias used as indestructible bedding plants in the summer garden, and tuberous begonias, often grown in hanging baskets kept outdoors in shady areas. Yet three types of begonia make superior houseplants: angel-wing begonias, fancy-leafed begonias, and winter-blooming begonias. Each type is discussed in detail on pages 12–14, since each has unique characteristics.
Begonias vary in size, longevity, and their most remarkable features. Angel-wing begonias make wonderful houseplants, since they produce showy leaves and pretty flowers. They are also reasonably long lived and easy to propagate by rooting stem cuttings. Fancy-leafed begonias are more challenging to grow, but their stained-glass leaves are among the most painterly plants in existence. Most people use winter-blooming begonias as short-lived color plants for winter windowsills. When the last flowers fade, you can discard the plants or keep them long enough to propagate new plants from rooted stem cuttings.
Light: Begonias need moderate light in summer, so they fare well when grown near an east window or under fluorescent lights. Those that bloom benefit from increased light in winter, when they perform best near a south or west window.
Temperature: Protect plants from chilling, as they are easily damaged by temperatures below 55°F/13°C. A temperature range of 65–75°F/18–24°C is ideal for most begonias.
Fertilizer: A steady diet of liquid fertilizer diluted to half the normal strength will keep begonias happy. Feed plants every 2 weeks while they are actively growing. Flowering begonias benefit from a high-phosphorous plant food. With fancy-leafed begonias, a balanced plant food is fine.
Water: Begonias are easily damaged by overwatering, yet they also suffer when their soil becomes extremely dry. Watering practices vary slightly with begonia type, but as a general practice it is prudent to allow the top inch of soil to become nearly dry between waterings. Begonias need moderate to high humidity. Make use of trays filled with dampened pebbles or use a humidifier in areas where you grow begonias. Avoid frequent misting, which can lead to problems with powdery mildew. Because of their need for humidity, begonias are good plants to grow in the same room with orchids, bromeliads, or ferns.
Soil: Provide begonias with a peaty yet well-drained soilless mix, such as African violet soil. Many good-quality potting soils that include perlite, which lightens the mix texture, are satisfactory for these plants. Heavy soil that dries slowly is not a good choice for begonias.
Repotting: Begonias often are sorted according to their root types, which can be fibrous or tuberous or include a thick rhizome that spreads over the surface of the soil. Root type influences container size and shape. Angel-wing begonias have fibrous roots and grow best when slightly rootbound in smallish pots. Most fancy-leafed selections develop rhizomes that grow near the soil’s surface, so the best containers for them are broad and shallow. Winter-blooming begonias usually need no repotting unless you want to shift them to a more decorative container.
Be careful not to plant any begonia in a large pot, as this can lead to problems with overwatering and root rot. After repotting, tap on the sides of the pot to tamp soil into place, but do not press it down hard with your fingers. A bit of air left in the potting mix is good for begonias.
Winter-blooming begonia (Begoni × hiemalis)
Propagating: All begonias can be propagated by setting stem tip cutting to root in a warm, humid environment. Fancy-leafed types can be propagated from petiole leaf cuttings, as is done with African violets (see page 302). They have the further distinction of being the only commonly grown houseplants that will develop plantlets when a leaf is pinned to the surface of dampened seed-starting mix. Although interesting, this method is slow compared to rooting petiole leaf cuttings, and not nearly as dependable. Some begonias can also be grown from seed, though hybrids are best propagated vegetatively, by rooting stem cuttings or leaves.
Small details: Begonias often react badly to changes in their environment, so it is wise to provide special care when bringing a new one into your home or office. Buy from a local source if possible, or purchase a small plant if it must be shipped. Reputable suppliers will ship plants only in warm weather. When you get the plant home, protect it from exposure to drafts and dryness by enclosing it in a loose plastic bag for a few days. Babying the plant along during its first few weeks in its new location can make a dramatic difference in a begonia’s short- and long-term welfare.
Pruned stems from angel-wing begonias make good cut flowers.
Leaves turn yellow or brown and fall off.
CAUSE: Overwatering.
REMEDY: Keep plants in small pots and water only after the surface becomes dry. Cool conditions and oversized pots contribute to this problem.
Tan spots on leaves; plants rot at the base.
CAUSE: Botrytis, a fungal disease.
REMEDY: If possible, remove affected leaves and propagate new plants from clean stem tip cuttings. This disease is common with rooted cuttings, and is best prevented by using a clean, pathogen-free rooting medium.
Spots with yellow halos on leaves.
CAUSE: Bacterial leaf spot.
REMEDY: On angel-wing and fancy-leafed begonias, remove affected leaves and increase air circulation. Dispose of infected winter-blooming begonias, as they carry this disease throughout their systems.
Flowers twisted and distorted, especially on winter-blooming begonias.
CAUSE: Thrips or mites.
REMEDY: See page 276 and check for presence of thrips. If present, pinch off affected leaves and buds and dispose of them. With good care, plants should rebloom in a few weeks. Mites are a more persistent pest. If flowers and new leaves are distorted, but no thrips are present, assume mites are the problem and dispose of the infested plant.
White powdery patches on leaves.
CAUSE: Powdery mildew, a fungal disease.
REMEDY: Remove affected leaves at the first sign of this disease. Increase air circulation around the plants. Older leaves are more susceptible than young ones, so propagating new plants annually is a good preventive strategy.
White cottony creatures on stems and leaves.
CAUSE: Mealybugs.
REMEDY: Isolate plant, and remove mealybugs by hand using a cotton swab dipped in alcohol. Repeat every 5 days until problem is controlled. Do not use oil sprays on begonias to control mealybugs or other pests.
Leaves of fancy-leafed begonias become pale and brittle.
CAUSE: Excessive light; dry air.
REMEDY: Move plant to a spot with reduced light and increase humidity. When new leaves appear with good color, propagate a few to grow a new plant.
In addition to the three types of begonias described below, there are many more available from specialty greenhouses and collectors.
Fancy-leafed begonias show mesmerizing variegation patterns.
FAMILY: BEGONIACEAE ORIGIN: SOUTH AMERICA
WITH MARVELOUSLY MARKED LEAVES and elegant pendant flower clusters, angel-wing begonias are the best types to grow as house-plants. There are dozens of species and named hybrids, which vary in size, leaf variegation, and flower color. Dwarf selections grow to only 12 in/30 cm and can be kept as table plants, while large ones become nearly shrublike within a few years’ time, often growing more than 36 in/90 cm tall and wide. Bloom time varies with cultivar, but most angel-wings bloom best in late winter and spring. The varieties named below are among the strongest rebloomers, often producing several flushes of flowers at different times of year.
Angel-wing begonia (Begonia × corallina)
Light: In spring and summer, bright filtered light with no direct sun. In fall and winter, bright light, including up to 4 hours of direct sun.
Temperature: Average room temperatures (65–75°F/18–24°C) year-round.
Fertilizer: Feed every 2 weeks with a high-phosphorous plant food mixed at half the normal strength.
Water: Allow soil to become dry to within 1 in/2.5 cm of the surface between thorough waterings.
Soil: A light, peaty soilless mix such as African violet potting soil.
Repotting: Repot annually in spring, shifting plant to a slightly larger container. Add pebbles or broken crockery to the bottom of the pot to increase weight and improve drainage. Very large specimens may need staking.
Longevity: 4 to 5 years, or indefinitely when propagated from stem tip cuttings.
Propagation: In spring or summer, root nonflowering stem tip cuttings in perlite, seed-starting mix, or a half-and-half mixture of peat moss and sand, as described on page 300.
Selections: ‘Bubbles’ is naturally dwarf, and produces orange-red flowers almost continuously. Pink-flowered ‘Looking Glass’ grows 12–36 in/30–90 cm tall, and features metallic silver leaves with olive green veins and red undersides. The dark reddish leaves of ‘Cracklin Rosie’ are speckled with pink, while long-limbed ‘Sophie Cecile’ has green leaves speckled with white. For hanging baskets, white-flowered ‘Orococo’ is a real beauty, with ivy-shaped, green-gold leaves edged with dark red.
Display tips: Angel-wing begonias are beautiful year-round, and deserve a prominent position where they can be admired constantly.
FAMILY: BEGONIACEAE ORIGIN: INDIA AND SOUTHEAST ASIA
BREATHTAKING TO BEHOLD, fancy-leafed begonias produce large leaves, to 6 in/15 cm long, dramatically marked with silver, green, pink, and burgundy. They need slightly less light than blooming begonias, and do well when grown under fluorescent lights. Pinching off buds and blossoms helps to maintain large, healthy leaves. To provide the high humidity these begonias crave, cover plants with a plastic tent at night, which works like a humidity chamber.
Fancy-leafed begonias sometimes shed their leaves and become dormant in winter. When this happens, clip off the withered leaves, allow the soil to become almost dry, and enclose the pot in a plastic bag. Keep it at 60°F/16°C until new growth appears, 6 to 10 weeks later.
Rex begonia (Begonia rex) and iron cross begonia (B. masoniana)
Light: Bright indirect light or fluorescent light year-round.
Temperature: Average room temperatures (65–75°F/18–24 cm) year-round.
Fertilizer: From spring through fall, feed every 2 weeks with a balanced houseplant fertilizer. In winter, feed plants monthly unless they are dormant.
Water: Water lightly yet frequently to keep soil constantly moist, but avoid overwatering. Plants need moderate to high humidity, but heavy misting can cause spots to form on leaves. Use trays filled with moist pebbles, a humidifier, or a plastic tent instead.
Soil: Use a light-textured, fast-draining medium such as African violet mix.
Repotting: Using shallow pots, repot plants in early spring so the rhizome is barely visible at the soil’s surface. Repot dormant plants as soon as new growth appears.
Longevity: Individual plants grow for 2 to 3 years, but can be kept indefinitely when propagated from stem or leaf cuttings.
Propagation: You can divide rhizomes when repotting, but it’s safest to root medium-sized leaves in early summer; handle these like petiole leaf cuttings see page 302.
Selections: ‘Iron Cross’ begonia (B. masoniana) features apple green leaves marked with dark brown crosses; leaves have a distinctively puckered texture. Leaves of various B. rex and B. boweri hybrids may be spotted, as in varieties with ‘Tiger’ in their name. Other hybrids show flaming variegation patterns in pink, silver, and various shades of green.
Display tips: Young plants are ideal for tank-sized terrariums. Larger plants demand exacting care and high humidity.
FAMILY: BEGONIACEAE ORIGIN: HYBRID OF TUBEROUS AND WAX BEGONIA SPECIES
CREATED IN 1955, WINTER-BLOOMING BEGONIAS are usually called Reiger hybrids. Ongoing breeding work continues to improve these plants, which are increasingly available on the brink of bloom in early winter. Mature plants in full flower stand 12–18 in/30–45 cm tall. They feature numerous camellia-like blossoms, to 2 in/5 cm wide, that may be red, pink, salmon, orange, or yellow. To prolong flowering time, gingerly pinch off individual flowers as they fade.
These plants are bred for a single season of enjoyment, but it is possible to keep them from year to year. When flowering subsides, taper off water and allow plants to become nearly dry. Cut foliage back to 3 in/7.5 cm, allow plants to rest for 6 weeks, then commence watering. When new stems are 3 in/7.5 cm long, cut them off and root them; discard the parent plant. In the fall, keep plants in natural light, since short days (less than 12 hours long) and cool nights trigger the formation of buds.
Winter-blooming begonia (Begonia × hiemalis)
Light: Near a cool, bright window.
Temperature: At night, 60°F/16°C. During the day, 70–75°F/21–24°C year-round.
Fertilizer: Feed every 3 weeks with a high-phosphorous fertilizer mixed at half the normal strength.
Water: Allow soil to dry to 1 in/2.5 cm below surface between thorough soakings. Keep plants on trays filled with damp pebbles to increase humidity.
Soil: Fast-draining mix that includes peat and perlite, such as African violet potting soil.
Repotting: Should plants become rootbound, shift them to slightly larger pots.
Longevity: 6 months, or indefinitely when propagated from stem tip cuttings.
Propagation: After plants have been cut back, rested, and begin to regrow, take 3 in/7.5 cm–long stem cuttings and root them in damp perlite, seed-starting mix, or a half-and-half mixture of peat moss and sand, as described on page 300.
Selections: Labeled as ‘Eliator’ or ‘Reiger’ hybrids, it is best to buy plants that show good bud color but have not yet begun to bloom.
Display tips: These are ideal plants for a sunny winter windowsill, where they can be teamed with amaryllis, cyclamen, and other winter-blooming plants.
COMMONLY KNOWN AS THE PINEAPPLE FAMILY, bromeliads grow wild in the rain forests of South America. The first bromeliad brought to Europe was indeed the pineapple, which Columbus found growing in the West Indies in 1493. After that, nearly 300 years passed before other bromeliads were introduced to the civilized world. These plants were grown in the conservatories of wealthy Europeans, and only gradually made their way into the houseplant world. Compared to other houseplants, bromeliads are definitely newcomers.
Blushing bromeliad (Neoregelia carolinae ‘Tricolor’)
All bromeliads are members of the Bromeliaceae family, which includes many plants that grow in the crotches of tree limbs, others that anchor themselves to rocks, and some that sink their roots into the forest floor. Bromeliads are unique in their ability to absorb moisture and nutrients from the air through tiny leaf scales, called trichomes. In addition, many species form rosettes of stiff leaves that overlap at the base to form a reservoir that holds water. Often called a cup or tank, this reservoir provides the plant with water and nutrients, which are released as insects and forest debris caught in the cup slowly decay.
In homes and offices, most bromeliads need a moderately moist environment where they can receive direct light for half the day. Some species tolerate dry air better than others, but all bromeliads grow best when humidity levels hover around 50 percent. They are therefore good plants to partner with ferns and other plants that need moist air. Bromeliad roots are quite skimpy, so they can be kept in smallish pots. For a dramatic display, you can grow young plants tethered to pieces of wood or large stones, with their roots wrapped in sphagnum moss.
The bracts of many bromeliads, such as this scarlet star (Guzmania lingulata), color up as the plants prepare to bloom.
All bromeliads bloom, usually when the plants are 3 to 5 years old. The blooms are actually clusters of colorful bracts, from which small, often vividly colored flowers emerge. The bracts persist for several weeks. After a bromeliad blooms, it slowly dies. But before it expires, the parent plant produces several offsets, or pups, which grow from the leaf crevices of the outermost leaves. When the pups are a third the size of the failing parent plant, they can be cut away, repotted, and grown into the next generation (see page 20).
Read below about the best potting soil and watering and fertilization practices for bromeliads. Never use any type of oil to clean bromeliad leaves or control pests, since oil can interfere with the work of the leaf scales. Also be careful where you place bromeliads, since the plants easily fall over when they become top-heavy, and some species have sharp spines along the edges of the leaves.
Light: Bromeliads vary in their preferences for light. Those with stiff leaves, such as urn plant and variegated pineapple, need more light than species that have more pliable foliage, such as queen’s tears. The plant profiles that follow give specific light recommendations, but you also can memorize the phrase “soft leaf/soft light, hard leaf/hard light,” as a good rule of thumb. In simple terms, bromeliads with soft leaves do well when grown near an east window, while those with hard leaves prefer the stronger light found by a west window. Soft-leafed bromeliads are often kept indoors year-round, while those with stiff leaves enjoy spending part of the summer outdoors in a place that receives a few hours of morning or afternoon sun.
Temperature: Average room temperatures are fine for most bromeliads, which should never be chilled by temperatures below 60°F/16°C. Some species, such as scarlet star (Guzmania) and flaming sword (Vriesea) resent temperatures above 80°F/27°C, so they are best kept indoors in climates with very warm summers. Others, particularly air plant (Tillandsia) and variegated pineapple (Ananas), are much more likely to bloom if treated to a warm summer outdoors. When moving plants outdoors in summer, gradually accustom them to increasing light levels, and never place them where they must endure intense midday sun. When shifted to bright light too quickly, bromeliad leaves can sunburn.
Fertilizer: Bromeliads are not heavy feeders, but they grow better when fed regularly in summer. Most grow best with an all-purpose liquid plant food diluted to half the normal strength. With most bromeliads, it is best to spray the fertilizer solution on the leaves and into the tank, while also dribbling a small amount into the soil. See the plant profiles for specific feeding recommendations for each species.
As bromeliads reach maturity, which usually takes 3 years or more, you can encourage the formation of flowers by feeding them a small pinch of Epsom salts (magnesium sulfate). Mix it into the water or fertilizer. The magnesium helps to initiate flowers. Another method for encouraging flower formation is to enclose a mature plant in a clear plastic bag along with a ripe apple or several apple cores for 1 to 2 weeks. The ethylene gas given off by the apple helps initiate bud formation. To avoid overheating, be sure to keep the plant out of direct sun when it is enclosed in a plastic bag.
Water: Most bromeliads gather water in their tanks, or reservoirs, and only a little moisture from natural rainfall penetrates the leaves to reach the roots. Keep this in mind when watering bromeliads. Many bromeliads are sensitive to minerals and chemicals in tap water, so they prefer rainwater or distilled water. Slow growth or browning of leaf tips can be due to hard water.
When watering bromeliads, spray a little water on the leaves, replenish the water in the reservoir, and dampen the soil only when it becomes very dry. A few species need more moisture in their soil, but as with other houseplants, overwatering greatly increases the risk of root rot, especially in winter when temperatures may be cooler. It is also good maintenance to dump out any water left in the reservoir after 10 days or so before refilling it with a fresh supply. If lifting the plant to empty the reservoir is too cumbersome, you can remove the old water with a bulb-type turkey baster. Place slightly less water in the reservoir when the plants produce a flowering spike. Excessive water left sitting in the cup can cause the base of a flower spike to rot.
Soil: Most bromeliads take up nutrients and moisture through their leaves and cups, so they do not depend on their roots for sustenance the way most other plants do. And, because many bromeliads are tree-dwellers, their roots are accustomed to sudden flushes of moisture followed by periods of dryness. Fast drainage is therefore important, along with some air in the root zone. To meet these needs, use a special bromeliad mix comprised of 1 part peat moss, 1 part sand or perlite, and 1 part chopped, decomposed tree bark or pine needles. This is an acidic mix, which is good. Never add lime to potting mixes used for bromeliads. If you prefer, potting soil developed for use with orchids is suitable for bromeliads.
Repotting: Bromeliads have scant root systems, and most grow best when kept in small pots. Restricted roots also control the plants’ size and may help them to flower, too. Young plants that are actively growing usually benefit from yearly repotting, which is best done in spring. After 2 to 3 years, plants often can be held in a 5–6 in/12.5–15 cm pot until they bloom and produce offspring. Whether you are repotting a large plant or small offsets, watch the planting depth and be careful not to set plants too deeply. Deep planting can cause a bromeliad to rot. If the plant has such skimpy roots that it will not stay upright in its new container, surround it with a “fence” of wood skewers pushed into the soil. Remove them in a month or two, after the plant has established a sound anchor of new roots.
Graceful queen’s tears (Billbergia nutans) gets its common name because of the drops of nectar that frequently “weep” from its pendulous blossoms.
Propagating: Bromeliads are grown from offsets, often called pups. Some species develop offsets before they flower, but it is more typical to see pups emerging after the parent plant has bloomed and begun to decline. If desired, you can trim back the failing leaves of the parent plant to give the pups more light, but do not remove it too soon. The offsets feed off of the deteriorating tissues of the parent plant.
Remove and repot the pups when they are one-third to one-half the size of the parent. It is usually best to do this by repotting the entire family. Use a sharp knife to separate the pups, and pot them in a lightly moist potting mix. Planting the offsets in a very wet medium can cause them to rot. Offsets that grow quickly may need repotting in only six months, but most grow slowly, and can wait until spring to be moved into a slightly larger container.
Wait until bromeliad pups are at least one-third the size of their parent plant to cut them away and repot them in small containers.
Small details: Patience is important with bromeliads, which must be mature before they will bloom. Under ideal conditions, the bromeliad life cycle is completed in 3 years, but plants often need a year or two longer when grown indoors. When buying plants, choose those that have not yet bloomed or have just begun to show a flower spike. Bromeliads in full bloom will expire within a few weeks, and you will have to wait years for another good show of flowers.
Giving pink quill (Tillandsia cyanea) a cool winter’s rest increases the chance that mature plants will bloom.
Tips of leaves turn brown.
CAUSE: Conditions are too hot or too dry. In winter, increase humidity by placing plant near a humidifier or misting it every other day. In summer, move plant to a shady place outdoors. Use a spray bottle to water the leaves, reservoir, and roots of the plant. Bromeliad pots should never be allowed to become completely dry.
Brown spots on leaves.
CAUSE: Sunburn.
REMEDY: Expose plants to direct sun gradually, especially in summer when sunlight is very intense.
Plant rots at the base without blooming.
CAUSE: Soil is too wet; insufficient air circulation.
REMEDY: Plants that develop root rot often cannot be saved.
Plant does not bloom.
CAUSE: Immature; receives insufficient light.
REMEDY: Move to a slightly brighter location. Keeping plants in small containers helps encourage flower formation. Most bromeliads do not bloom until they are at least 3 years old. See “Fertilizer” on page 18 for more tips on promoting bromeliad flowers.
Flower spike rots at the base.
CAUSE: Too much water in reservoir.
REMEDY: Reduce the amount of water placed in the reservoir after the flower spike emerges. Instead, water plants by spraying the leaves until thoroughly wet, then dribbling water into the pots.
Offsets die without rooting.
CAUSE: Offsets taken when too small; humidity too low.
REMEDY: Wait until the parent plant is nearly dead to remove pups. For the first 3 to 4 weeks after repotting offsets, enclose them in a plastic bag to maintain very humid conditions.
Brown disks on leaves.
CAUSE: Scale insects.
REMEDY: These sucking insects occasionally infest bromeliads. Gently remove by hand by scraping them off with your fingernail. Repeat every few days, then spray plants with insecticidal soap after testing plant for tolerance. See page 273 for more on this pest.
White woolly patches on leaves, especially in crevices between leaves.
CAUSE: Mealybugs.
REMEDY: Mealybugs are an occasional problem on bromeliads. Remove with a cotton swab dipped in alcohol; repeat every 3 days until the plants are clean.
Bromeliads with soft, arching leaves, such as queens’ tears (Billbergia nutans), require less light than those with stiffer leaves.
In the following pages, eight of the most popular, easy-to-grow bromeliads are described in detail. They are listed in alphabetical order by botanical name, but you may not know a bromeliad’s botanical name if you bought it without benefit of an identification tag. This chart will help you identify which bromeliad you have, so that you can then turn to the appropriate plant profile to get to know your bromeliad better.
FAMILY: BROMELIACEAE ORIGIN: BRAZIL
THE STIFF, UPRIGHT SHAPE OF URN PLANT serves it well in its natural habitat — the floor of South American rain forests. The tough, arching leaves have a waxy finish, which helps the plant gather water in its reservoir. Individual leaves can grow to 15 in/37.5 cm long, and well-grown plants may reach 20 in/50 cm in height. Mature plants produce a quilled, pinkish orange bract that persists for 4 to 6 weeks. If a 4-year-old plant shows no signs of blooming, try pushing it along with Epsom salts and ethylene gas released by fresh fruit (see page 18). Spring is the best season to induce bloom; bright light also promotes flowering. After flowering, urn plant usually produces two to three pups.
Urn plant (Aechmea fasciata)
FAMILY: BROMELIACEAE ORIGIN: BRAZIL AND PARAGUAY
THE SAME SPECIES AS THE EDIBLE PINEAPPLE, ivory pineapple is grown primarily for its long leaves with creamy margins studded with sharp spines. Plants can get quite large, to 36 in/90 cm tall and 6 ft/1.8 m across, but keeping them in 8 in/20 cm pots helps to control their size. Plants that are 5 to 6 years old produce a pinkish fruiting spike that slowly grows into a small brown pineapple over a period of 3 months. Although it lacks the sweet flavor of cultivated pineapples, which grow in hot sun, it is fun to watch as it matures.
Potted pineapples benefit from strong light and warm temperatures, so it is best to move them outdoors in summer. Gradually accustom the plants to increased light. Move the plants back indoors when nights begin to cool in the fall, and then place them in a very warm, brightly lit location.
Ivory pineapple (Ananas comosus ‘Variegatus’)
Light: In summer, move plant outdoors to partial sun. In fall, winter and early spring, a half day of direct light from an east or west window.
Temperature: In winter, warm (above 65°F/18°C). In summer, very warm (to 85°F/29°C).
Fertilizer: From late spring through summer, feed plant every 2 weeks with liquid plant food mixed at half the normal strength. In winter, feed monthly.
Water: In summer, provide moisture by thoroughly spraying the leaves with water twice weekly. Also water the roots when the top half of the soil becomes dry. In winter, plants kept indoors need less water due to lower temperatures and less sun. Use similar practices about once a week.
Soil: Orchid potting mix or African violet soil. This bromeliad needs a heavier soil than most other species.
Repotting: Every 2 years in spring. When repotting, do not press the soil down, as this plant likes a little air around its roots. Wear gloves and long sleeves when handling this spiny plant.
Longevity: Individual plants live 5 to 6 years.
Propagation: If the plant produces a fruit, cut off its top when the leaves in the rosette are 4 in/10 cm long, allow it to dry for a day, and then pot it in a lightly dampened mixture of peat moss and sand. You also can pot up offsets that emerge after the parent plant begins to die.
Selections: You can grow a regular pineapple by cutting off the top and rooting it, but the variegated form makes a much more attractive houseplant.
Display tips: This plant needs plenty of room and abundant sun. It makes a good floor plant in rooms with large windows, particularly when grown in close company with tropical-looking palms.
FAMILY: BROMELIACEAE ORIGIN: ARGENTINA AND BRAZI
POPULAR AND EASY TO GROW, queen’s tears gets its name from the tendency of the flowers to weep droplets of nectar. It is also a willing producer of offsets, which can be shared among friends, hence its other common name, friendship plant. Young plants grow into upright rosettes. As the leaves age, they arch outward. Mature plants are typically 16 in/40 cm tall and up to 30 in/75 cm wide. Plants bloom when they are 2 to 3 years old, usually in spring, bearing pendant red or pink bracts with green, purple, or yellow flowers inside. Too much light can make the leaves take on a reddish cast, but increased light levels available outdoors in summer encourage mature plants to bloom the following spring. This bromeliad tolerates dry indoor air better than others, but still benefits from being kept in a spot where it can be misted often to increase humidity.
Queen’s tears (Billbergia nutans)
FAMILY: BROMELIACEAE ORIGIN: BRAZIL
A SMALL BROMELIAD, earth star is an excellent choice for humid rooms where space is limited. Mature plants are only 5 in/12.5 cm high and 6 in/15 cm across. Unlike other bromeliads, earth star’s flowers are small and hidden, so it is grown primarily for its starry, sharp-tipped wavy leaves. The coarse leaf scales are easily seen on most cultivars, and they do a good job of absorbing moisture and nutrients. Strong light intensifies the leaf colors of pink or variegated earth stars. Older plants often flatten out a bit before they bloom, and then slowly fail. Use scissors to trim back the leaves by half their length, which speeds the growth of the emerging offsets.
Because of its small size, earth star is the preferred bromeliad for growing in homes. Its unique texture brings surprising drama when earth star is grouped with ferns and other foliage plants that like high humidity.
Earth star (Cryptanthus acaulis)
FAMILY: BROMELIACEAE ORIGIN: CENTRAL AND SOUTH AMERICA
MANY OLDER STRAINS OF SCARLET STAR grew quite tall, but most modern named varieties are smaller, reaching a mature size of 10 in/25 cm tall and 12 in/30 cm wide. This bromeliad has a rather upright posture, and its glossy green leaves add to its appeal. A flamboyant bloomer, in its third or fourth year scarlet star produces a brightly colored quilled spike, which emerges just above the foliage in the plant’s center. As the flower spike fades, usually 6 or more weeks after it appears, pups emerge from near the base of the plant. Although scarlet star appreciates high humidity, it is less demanding of light than other bromeliads, and often grows beautifully in the bright artificial light of offices.
Scarlet star (Guzmania lingulata)
FAMILY: BROMELIACEAE ORIGIN: BRAZIL
BLUSHING BROMELIAD GETS ITS NAME from the way the leaves in the center of the plant turn bright red as the plant begins to flower (see photo). The blossom itself is not showy and stays nestled deep in the crown. However, the colored vase persists for a few months, until the parent plant dies back and makes way for three or more new offsets. Full-sized blushing bromeliads, sometimes called “neos,” become broad, flat-topped plants, 25 in/62.5 cm wide and 12 in/30 cm tall, and plants of any size need abundant warmth and humidity. To grow well, they must feel convinced that they are in a jungle, yet they also need abundant sun. This bromeliad is therefore not for everyone, but is a good choice if you have a bright sunroom that is kept humid at all times.
Blushing bromeliad (Neoregelia carolinae ‘Tricolor’)
Light: Bright light with a half day of direct sun year-round. Responds well to being grown in a sunny yet humid place outdoors in summer.
Temperature: Average to warm room temperatures (65–80°F/18–27°C), with no chilling below 50°F/10°C.
Fertilizer: Feed monthly with a high-phosphorous (low-nitrogen) fertilizer mixed at half the normal strength. Feed the leaves, roots, and reservoir.
Water: Keep roots lightly moist, and replenish water in reservoir every 10 days, or more often in summer. This bromeliad grows best in high humidity, above 50 percent.
Soil: Potting soil amended with one-third part peat moss, or African violet soil.
Repotting: Repot annually in spring until plant fills a 5 in/12.5 cm pot.
Longevity: Individual plants live 3 to 4 years.
Propagation: Wait until the parent plant dies back to pot up offsets, which often have very skimpy roots. Keeping newly potted offsets in a warm, humid enclosure, such as a roomy plastic bag, speeds the rooting process.
Selections: There are numerous named varieties, most of which have cream stripes in their leaves. ‘Martin’ is quite vigorous, as is the slightly smaller ‘Compacta’.
Display tips: Because of its large, spreading shape, this bromeliad needs plenty of space. It is at its best when viewed from above.
FAMILY: BROMELIACEAE ORIGIN: CENTRAL AND SOUTH AMERICA
TILLANDSIA BROMELIADS are the rootless wonders of the plant world. Some species do have roots, but these are used primarily to anchor the plants in place. Tillandsias take up moisture and nutrients through the leaves, and only one species, T. cyanea (pink quill), can be grown in a pot. Others can be pinned, tied, or even glued onto a mount, such as a gnarled piece of wood or a seashell. All are small plants with thin, gray-green leaves that seldom spread more than 6 in/15 cm high and wide. Like other bromeliads, tillandsias bloom and then produce offsets. Giving them a cool winter rest increases the probability that mature plants will bloom. Most tillandsias reach maturity in 3 to 5 years.
Pink quill (Tillandsia cyanea)
FAMILY: BROMELIACEAE ORIGIN: TROPICAL AMERICA
ONE OF THE SHOWIEST BROMELIADS, flaming sword features stiff, arching leaves banded with maroon, which form a tight vase in the center. Mature plants grow 20 in/50 cm tall and 24 in/60 cm wide. Flaming sword is not as easy to grow as some other bromeliads, but it will succeed when provided with bright light, warm temperatures, and moderate to high humidity. If all goes well, a 3- to 4-year-old plant will reward you with a tall, flattened flower spike, which is usually bright red, with small yellow flowers emerging from the bracts. The spike persists for several weeks, after which the plant slowly declines while producing one or more offsets. Wait until the parent plant is quite far gone to propagate a new plant from the pup.
Flaming sword (Vriesea splendens)
Light: Bright indirect light year-round, with some direct sun in winter.
Temperature: Warm (70–80°F/21–27°C) year-round.
Fertilizer: Feed monthly with an all-purpose houseplant fertilizer mixed at half the normal strength. Feed the leaves, roots, and reservoir.
Water: Keep soil lightly moist at all times, and refill reservoir every 2 weeks with fresh water. Mist weekly, and keep in a humid room.
Soil: Bromeliad mix or orchid potting soil.
Repotting: Repot young plants after 2 years, and limit pot size for mature plants to 6 in/15 cm.
Longevity: Individual plants live for 3 to 4 years.
Propagation: After flowering, this bromeliad usually produces one robust pup. Allow it to grow until it is at least 8 in/20 cm tall before detaching it, potting it up, and discarding the parent plant.
Selections: There are many named varieties, which vary in leaf variegation and the shade of the flowering spike. Purchase plants that have not yet bloomed, or have just begun to produce a flowering spike.
Display tips: The dramatic leaf colors make this plant a strong focal point even when it is not in bloom. Because of its width, it is a good plant to display on a raised platform, with smaller ferns or other low-light plants beneath it.
GROWING BEAUTIFUL INDOOR FLOWERING PLANTS from onion-shaped bulbs, nubby corms, or fleshy tubers planted in pots carries with it the same excitement as growing flowers from seeds, only better. Bulbs, corms, and other types of storage roots are packed with the nutrients plants need to grow and bloom, and some actually contain the cells of the flowers to come. Provide these plants with light and temperature regimens that suit them, and you will be delighted with the bursts of color at different times of the year.
Bright tulips, forced into bloom in pots, are an easy way to bring springtime indoors.
This chapter includes twelve blooming plants that are grown by planting dormant roots of one kind or another. Those included here are commonly sold as indoor plants, and can be expected to bloom for more than 3 weeks when given adequate care. Some, such as oxalis, bloom almost year-round.
A summer-blooming bulb in the garden, clivia can be forced for early bloom indoors in February or March.
Bulbs, corms, and tubers vary in their need for and tolerance of cold, so they are broadly divided into two groups: spring-flowering bulbs and warm-natured bulbs. Most spring-flowering bulbs are planted in fall, after which they must have several weeks of chilling before they will bloom in spring. Warm-natured bulbs, corms, and tubers that do not require chilling are regarded as “summer” bulbs, though some of them bloom in winter and spring. Most warm-natured bulbs need a dry rest period between cycles of active growth.
The plants in this section are organized into the two broad groups listed below. I refer to all as “bulbs” in the interest of simplicity, though some grow from corms and tubers, which are quite different from true bulbs in terms of botanical structure. See the chart for further guidance on plant characteristics and seasonal growth cycles. The plant profiles, which are listed by botanical name, provide detailed information on how to grow each plant for maximum satisfaction.
When spring-flowering bulbs are grown for indoor bloom, the process is called “forcing” because it tricks the bulbs into behaving as if they have been grown outdoors through a long, cold winter. With the exception of paperwhite narcissus, spring-flowering bulbs require a minimum chilling period of 8 to 15 weeks before they will bloom. Part of the chilling period can take place in your refrigerator, but most spring-flowering bulbs also need time to grow roots in cold soil before they start expending their energy putting out leaves and flowers.
Very fragrant signs of spring, grape hyacinth (Muscari species) are ideal bulbs for forcing.
Stores and mail-order companies begin selling spring-flowering bulbs in late summer and early autumn. As soon as you buy them, put the bulbs in your refrigerator (keep them in perforated plastic bags). Store them away from apples and other fruits, which give off ethylene gas that can cause bulbs to rot. On a calendar, write down the date when you put your bulbs in the refrigerator — the official beginning of their chilling period.
Spring-flowering tulips and hyacinths frame this bright arrangement of other seasonal favorites (from top to bottom, cineraria, winter-blooming begonia, primrose).
How you approach the next step, planting the bulbs, depends on two things: your climate, and whether or not you have a place where the planted bulbs can be held at temperatures between 35–45°F/2–7°C for another couple of months.
Where winters are cold. Rig up a “chilling chamber” by placing the planted, lightly dampened pots in a cooler, plastic storage bin, or stout cardboard box kept on your porch or patio, or perhaps in an unheated garage. Then fill the box with chopped bark or other loose mulch material. If you want to keep the pots clean, enclose them in plastic bags before filling in around them with mulch. Stored in such a box, the bulbs should not actually freeze, and will be out of the reach of mice and squirrels, who like to eat bulbs for breakfast.
Where winter are warm. If your winter temperatures stay above 50°F/10°C or you simply have no space outdoors to use as a chilling chamber, you can plant bulbs in pots, water them lightly, enclose them in plastic bags, and return them to your refrigerator. This takes up refrigerator space, but most people can find room for a few small pots on the back of a middle shelf. Another option is to find a garden center (or mail-order company) that sells pre-chilled bulbs. These can be planted as soon as you buy them, though you’ll still need to keep them in a cool place for a few weeks while the bulbs grow roots.
Fragrant paperwhite narcissus need no chilling period, and they can even be grown in a container filled with pebbles and water.
You can force bulbs in any containers that have drainage holes in the bottom and are at least three times as deep as the height of the bulbs. These can be the same containers in which you plan to display the bulbs when they bloom, or you can use small individual pots. Later on, when the chilling period is over and the bulbs produce their first green growth, you can gently transplant them to prettier containers if you like.
All-purpose potting soil is fine for forced bulbs, and you can mix in some small pebbles or gravel if desired to give the pots extra weight. Plant bulbs pointed side up, only so deep that the tops of the bulbs are barely covered with soil. Water the pots until the soil around the bulbs is thoroughly dampened, and move them to their chilling chamber. Then forget about them until the chilling time is up.
Hyacinths fill the room with their heavy fragrance.
When your calendar says that the bulbs have chilled long enough (counting any time they spent in the refrigerator), examine the containers and look for the two signs that the bulbs are ready to come inside: roots showing in the pots’ drainage holes, and a green shoot emerging from the tops of the bulbs. Move the containers to a cool room where temperatures are 50–60°F/10–16°C, such as your basement or a spare bedroom where the heat can be turned off. If the coolest spot you can manage has little light, don’t leave the bulbs there for more than a week or so. If the place has light, the bulbs can stay there for 2 to 3 weeks. During this time they will slowly grow leaves and the flower buds will begin to appear. If you can, step up light but not temperature during this period.
Three weeks after being brought indoors, your bulbs will be well on their way to blooming. At this point they need abundant light and constant gentle moisture, but they may grow too fast if kept in a very warm spot. To make flowers last as long as possible, keep the bulbs in your coolest room at night. This is also the best way to handle purchased plants that are already coming into bloom (be sure to choose pots in which the buds have not yet opened).
Forced spring-flowering bulbs grow in such cramped conditions that it is difficult for them to store up the nutrients needed to bloom again if forced a second time the following year. However, small bulbs such as grape hyacinth and other “little” bulbs, discussed on page 36 in “Spring Surprises from Small Packages,” can sometimes regain the strength they need to prosper if they are fed and watered regularly until they can be transplanted to the garden in mid- to late spring. In general, it is best to discard forced hyacinths, daffodils, and tulips after they have bloomed. If you want to grow bulbs that can be brought back into bloom year after year, the best candidates are achimenes, amaryllis, and some of the other warm-natured bulbs discussed on the following pages. But do not bypass spring-flowering bulbs just because they are one-shot wonders. A plant-lover’s life is incomplete without the occasional fragrance of hyacinths or the cheery company of miniature daffodils.
Muscari are the most dependable and long-flowering of the so-called “little” spring-flowering bulbs, but several other species, described below, can be forced into bloom in the same way. Garden centers sell these bulbs alongside tulips and daffodils in the fall. Plant little bulbs close together in small pots, and allow them 12 to 15 weeks of chilling time. Expect the flowers to last about 2 weeks indoors. Like grape hyacinth, these little bulbs often do well when transplanted to the garden after their indoor blooms have faded. Here are some others to try:
• Chinodoxa luciliae, often called glory-of-the-snow, produces 8 in/20 cm–tall stems studded with up to a dozen small, starry, blue or pink flowers.
• Crocus hybrids bloom only for a week or so, but they are a beautiful way to celebrate the coming of spring on a cool windowsill. Plants grow to only 6 in/15 cm tall.
• Iris reticulata, or dwarf iris, features showy but shortlived blossoms in shades of blue, often with white or yellow markings, that grow only 4–8 in/10–20 cm tall.
• Puschkinia scilloides, or striped squill, looks like a tiny, 6 in/15 cm–tall hyacinth, with blue blossoms marked with darker blue stripes.
• Scilla species, including S. bifolia, S. mischtschenkoana, S. peruviana, and S. siberica, feature dainty little blue or white blossoms on stems that grow 4–8 in/10–20 cm tall.
Framed by their dark green foliage, the white trumpets of Easter lilies appear especially pristine.
Pots of caladiums can be sunk in the garden in summer, and brought back indoors when temperatures drop in the fall.
The bulbs in this group come from different parts of the world, from the tropics to the arid temperate climate of South Africa, so they are not all grown the same way. Oxalis is nearly perpetual, hardly ever needing a rest period, while amaryllis, clivia, and most others do best when allowed a period of dormancy. Indeed, the seasonal light and temperature cycles of warm-natured bulbs vary so much that few generalizations can be made.
Most warm-natured bulbs that grow well indoors need a period of bright light or cool temperatures to coax them into bloom; many respond well to winter sun. In summer, they are best grown in shadier spots and can be moved outdoors onto a porch or patio provided they are not exposed to temperatures below about 55°F/13°C. If you have a garden, you can even bury the pots halfway in loose soil, which insulates the roots from daily temperature fluctuations and helps keep them moist at the same time.
Most warm-natured bulbs have in common a need for regular fertilization before and after they bloom. You might expect this with plants that, while somewhat seasonal, still grow for a long time. A high-phosphorous plant food is ideal for these plants.
Perhaps the best thing about warm-natured bulbs is that they provide bursts of color at different times of the year. You can have achimenes and caladiums through the summer, amaryllis in winter, clivia in late winter, and calla lilies in spring. While one species is at rest, there is always another ready and waiting to take its place. Whether you start with purchased plants or dormant roots, most warm-natured bulbs can be counted upon to reward their keepers with several seasons of delight. The plant profiles provide detailed information on the life cycles and cultural requirements for these beautiful plants.
Potted amaryllis bulbs fill a bright window in winter.
No leaves or flowers.
CAUSE: Bulbs have died, usually because fungi entered them. Infected bulbs rot and feel light or mushy when you remove them from the pots. Spring-flowering bulbs that freeze hard for a long time frequently rot when they thaw.
REMEDY: Discard bulbs and potting soil, and thoroughly clean pots. Start over in the proper season with bulbs from a reputable supplier. Use clean, uncontaminated potting soil.
Leaves appear, but no flowers.
CAUSE: Improper storage, especially at high temperatures, can cause the flowering parts of the bulb to die, though the leaf-producing tissues survive. Small, low-quality bulbs may lack sufficient specialized cells to develop flowers. High-nitrogen fertilizer also can cause plants to produce lush leaves and few flowers.
REMEDY: Buy bulbs soon after they become available, bypassing those that have been on store shelves a long time. Obtain the biggest and best bulbs or tubers you can find, and buy from a reputable dealer.
Leaves emerge from near the side of the pot.
CAUSE: Bulb or corm was planted upside down.
REMEDY: The tops of bulbs and corms are usually pointed, but if you can’t tell the top from the bottom, plant the root on its side.
Leaves grow slowly and buds drop off before flowers open.
CAUSE: Dry conditions; trauma from environmental change.
REMEDY: Increase water and humidity. Avoid moving plants at the early bud stage of development.
Leaves look fine but buds drop off before flowers open.
CAUSE: Sudden change from cold to warm conditions.
REMEDY: When spring-flowering bulbs are moved from their chilling chamber, keep them in a cool room for at least a week. The change from cold to warm should be as gradual as possible.
Plants grow tall and have trouble staying upright.
CAUSE: Too warm during early growth phase, or not enough light.
REMEDY: Crowding bulbs helps dwarf their topgrowth, as does growing them in a cool room. Do not move to a warm place until buds are ready to open. Light-starved plants stretch toward the brightest light.
Leaves look unhealthy and show tiny yellow dots.
CAUSE: Spider mites.
REMEDY: See page 274 for the best ways to control this pest. Discard infested plants that are short lived, because spider mites can easily spread to other plants. When purchasing plants, check them thoroughly for this and other pests.
Container-grown bulbs and tubers each have distinctive bloom seasons, making it easy to share the company with blooming bulbs during every season of the year. Clockwise, from top left: Oxalis, achimenes, paperwhite narcissus, and freesia
FAMILY: GESNERIACEAE ORIGIN: CENTRAL AND SOUTH AMERICA
THERE IS AN UNDENIABLE ALLURE to a beautiful blooming plant that grows from tiny rhizomes planted indoors in spring, blooms prolifically from summer to fall on a bright windowsill or shady patio, and then becomes dormant in winter, when space is needed by other plants. This is the life cycle of achimenes, a relative of African violet that can be grown in hanging baskets or pots, and blooms in colors ranging from rich blues and purples to yellow, salmon, red, and pink.
Cupid’s bow (Achimenes hybrid)
Plant the dormant rhizomes, which resemble tiny pinecones, in a 3–6 in/7.5–15 cm container in spring. Set them 1 in/2.5 cm deep in African violet potting soil, and keep the container lightly moist at around 70°F/21°C. Pinch the stem tips when they are 3 in/7.5 cm long to promote branching. Through the summer, grow the plants indoors or out, in a bright location where temperatures range in the 70°sF/20°sC. Fertilize weekly with a high-phosphorous plant food. In October, allow the plants to dry until the foliage withers to brown. Gather the rhizomes and store them in bags, padded with a handful of dry peat moss or vermiculite and kept at 60°F/16°C. In spring, discard any rhizomes that are small or shriveled, and replant the rest.
Light: Bright filtered light.
Temperature: Nearly constant at about 70–75°F/21–24°C.
Fertilizer: Feed weekly with a high-phosphorous fertilizer while plants are actively growing. Stop feeding in late summer.
Water: Provide as much lukewarm water as needed to maintain constant, even moisture.
Soil: African violet mix.
Repotting: Replant the best rhizomes in spring in fresh soil.
Longevity: Many years.
Propagation: Replanting of rhizomes; rooted stem tip cuttings.
Selections: Grown in hanging baskets, the cascading types are easy and rewarding. Fine varieties include pink ‘Charm’ and blue ‘Blue Monarch’. The best reds are hybrids such as ‘Inferno’ and ‘Scorpio’.
Display tips: Achimenes are spectacular when grown in a hanging basket at eye level.
FAMILY: ARACEAE ORIGIN: SOUTH AMERIC
CALADIUMS DON’T REALLY BELONG among the flowering plants, since they only occasionally produce finger-shaped flowers. Yet each colorful heart-shaped leaf easily does the work of ten flowers. Caladiums are among the showiest houseplants you can grow, with large nodding leaves in pink, green, red, and white, often with contrasting veins and edges.
Angel wings (Caladium hybrid)
Grow caladiums in summer, when warm temperatures and abundant light prevail. Purchase tubers in spring and plant them in pots, no more than 3–6 in/7.5–15 cm pot; cover tubers with 1 in/2.5 cm of potting mix. Water well, and set in a warm place, such as atop your refrigerator. Leaves will begin to unfurl in a few weeks, and will get bigger and better as they are exposed to more light and warmth. Move them outdoors only if temperatures there will not dip below 60°F/16°C at night. If you want to keep plants from year to year, allow the pots to dry until the leaves wither in the fall. Clip off the old leaves, and then store the pots in a closet or other dark place where temperatures will remain above 55°F/13°C. Repot the tubers in fresh soil the following spring.
Light: Bright to moderate light.
Temperature: Warm to very warm (70–85°F/21–29°C) during active growth.
Fertilizer: Feed plants weekly with a high-nitrogen foliage plant food. Caladiums are all leaf, so they benefit from abundant nitrogen.
Water: Keep soil constantly moist, and maintain high humidity.
Soil: Any good potting soil.
Repotting: Move to larger pots if the plants become rootbound during the growing season.
Longevity: Showy season lasts 6 months or more. Tubers can usually be grown in pots for 2 years before they lose quality, evidenced by sparse, undersized leaves.
Propagation: In spring, cut off any sections of root that appear shriveled and dead, and replant the healthy section.
Selections: Dwarf ‘Miss Muffet’ has creamy white leaves liberally sprinkled with red spots. All varieties with ‘Florida’ in their name tolerate cool conditions better than most larger caladiums.
Display tips: Place caladiums where you want to evoke a tropical feel. They are a wonderful way to color up collections of tropical foliage plants.
FAMILY: AMARYLLIDACEAE ORIGIN: SOUTH AFRICA
FIRST COLLECTED IN 1815, clivia is easy and exciting to grow as an indoor-outdoor houseplant. Plants more than 3 years old can be counted upon to bear clusters of 10 to 20 tubular orange, salmon, red, yellow, or white flowers in late winter. Atop thick, ropelike roots, deep green strappy leaves 2 in/5 cm wide and 24 in/60 cm long persist year round, and the plants get bigger and better with time. A special temperature regimen is needed to make a clivia bloom, but this is easily accomplished by keeping the plant outdoors in fall during the last month before the first frosts arrive, and then moving it to your coolest indoor room and keeping it rather dry until midwinter. After this cool, dry rest, a gradual increase in water, coupled with normal room temperatures, leads to a beautiful show of blossoms in February or March.
Clivia (Clivia miniata)
Light: Indoors in winter, moderate light from an east window. Outdoors from late spring to fall, mostly shade with no midday sun.
Temperature: From midwinter to spring, average room temperatures (60–75°F/16–24°C) indoors. In summer, warm temperatures (70–80°F/21–27°C) outdoors. In fall, cool temperatures (35–55°F/2–13°C) outdoors.
Fertilizer: Spring to fall, feed every 2 weeks with a balanced or high-phosphorous plant food. In winter, do not feed.
Water: Spring to fall, keep soil lightly moist. Leach pots in summer to remove accumulated salts (see page 263). In fall and early winter, allow a dry period, watering only enough to keep leaves from wilting. During the second half of winter, gradually increase water.
Soil: Orchid potting mix.
Repotting: Plants like to be root-bound, and need repotting only every 3 years. Use a broad, heavy pot to prevent toppling.
Longevity: 10 to 20 years, or indefinitely when divided every 5 to 7 years.
Propagation: Purchased plants are grown from seed. At home, it is best to cut off the flower stalk at the base when the blossoms shrivel, and propagate clivia by carefully dividing old plants. Young, growing crowns survive repotting better than older ones.
Selections: Orange, red, and salmon strains are much more affordable than comparatively rare yellow or white clivias.
Display tips: Celebrate clivia’s bloom season by moving the plant to your most often-used room when the flowers appear.
FAMILY: IRIDACEAE ORIGIN: SOUTH AFRICA
THE SAME SWEET FREESIA FRAGRANCE found in bath and body products can be experienced straight from the blossom when you grow these delightful flowers indoors. Doing so requires that you mimic the climate in their native home of South Africa — this is not difficult, but it is quite different from the way other blooming bulbs are handled. The temperature regimen freesias need is easily accommodated by planting them in early fall.
Freesia (Freesia corymbosa)
Begin in summer by keeping little freesia corms in a very warm (80°F/27°C) spot for two months, such as atop your refrigerator or hot-water heater. Plant the conditioned corms in well-drained pots, six to eight to a 6-inch pot. After watering, keep the pots at average room temperatures for a month. Move them to a cooler (60°F/16°C), brightly lit room for 2 weeks while the buds form. Get them situated in a cool window as the blooms open. Freesia stems often grow 18 in/45 cm long and need to be taped or staked to hold them upright. After the flowers fade, continue to feed and water the plants until they die back. Allow the pots to dry completely, gather up the corms, and repeat the cycle.
Light: Bright light from an east or west window.
Temperature: Cool (55–65°F/13–18°C) during their active growth period.
Fertilizer: Feed every 10 days with a balanced or high-phosphorous plant food.
Water: Keep soil lightly moist during the growth period, but avoid overwatering the plants.
Soil: Any well-drained potting soil.
Repotting: Replant yearly, after the annual warm-temperature conditioning period.
Longevity: Several years.
Propagation: When repotting, sort the corms and discard very small ones or those that are old and woody, then replant the healthiest specimens.
Selections: Freesias are available in single- and double-flowered types, in individual colors or mixtures. Those with single flowers are not as prone to falling over as are heavier double-flowered strains.
Display tips: Freesias in full flower will fill a window and perfume a room. If they become too rangy, cut the stems and use them as cut flowers.
FAMILY: AMARYLLIDACEAE ORIGIN: SOUTH AMERICA
A FAVORITE BULB TO BRING INTO BLOOM in winter, amaryllis often are sold in kits that are marketed especially for the Christmas holiday season. These big, dependable bulbs bloom in red, white, or pink, and there are many bicolors.
Amaryllis (Hippeastrum hortorum)
All amaryllis bloom 6 to 8 weeks after planting. Set bulbs in a container that leaves only 2 in/5 cm to spare between the bulb and the pot’s edge. Good drainage is essential, as is setting the bulb high in the pot, so the top third of the bulb is exposed. Water well and place the planted bulb in a cool (60°F/16°C) place for a month, until a 6 in/15 cm shoot appears. Then move it to good light and feed it with a balanced fertilizer every 10 days. Most big bulbs produce two flower stalks. After the flowers fade, cut off the stalks and continue to feed and water the plants. In late summer, allow the plants to dry very gradually. Cut off the old leaves, and let the bulbs rest in a cool (50°F/10°C) place for at least 10 weeks. Repot firm, healthy bulbs 6 to 8 weeks before you want a repeat show of flowers.
Light: Bright light during active growth period
Temperature: Cool (55–70°F/13–21°C) during early growth and flowering, followed by warmer temperatures (70–85°F/21–29°C) after the flowers fade.
Fertilizer: Feed with a balanced all-purpose plant food every 10 days.
Water: Keep soil lightly moist during the active growth period. Induce dormancy by allowing the pots to gradually dry out in midto late summer.
Soil: Any good potting soil, or a three-way mixture of peat moss, sand, and potting soil.
Repotting: Replant each year in winter, after bulbs have rested for 10 to 15 weeks.
Longevity: Several years.
Propagation: Very vigorous varieties may produce offset bulbs around the mother bulb. Allow these to remain attached for two seasons before breaking them off and planting them in their own pots.
Selections: Pale pink and white ‘Appleblossom’ is an old favorite. ‘Scarlet Baby’ and ‘Baby Star’ are more compact and often produce numerous blooms followed by offset bulblets.
Display tips: Tall amaryllis look best when grouped with low-growing foliage plants, so that the dramatic flowers rise from a sea of green.
FAMILY: LILIACEAE ORIGIN: TURKEY
BEAUTY, FRAGRANCE, AND EASE OF CULTURE have made hyacinths the most popular bulb to grow indoors. Each bulb produces a robust spike packed with sweetly scented florets, which come in various shades of blue and pink, as well as white, red, yellow, and coral. Tremendously reliable, an old Persian saying summarizes their allure: “If you have two coins, use one to buy bread, the other to buy hyacinths, for the joy of your spirit.”
Hyacinth (Hyacinthus orientalis)
To coax hyacinths into bloom indoors, follow the instructions in the section “Forcing Spring-Flowering Bulbs,”, allowing at least 12 weeks of chilling time. Hyacinths can be left out in the cold for much longer, and bringing forced bulbs indoors one at a time helps stretch the bloom season. You can grow hyacinths in soil, decorative pebbles, or in plain water. Garden gift shops sell hourglass-shaped hyacinth vases that hold the bulb in place while allowing sufficient room for the roots. Hyacinth flowers last about 2 weeks when the plants are kept in a cool room. Sadly, hyacinths that are forced to bloom indoors never regain their strength and are best discarded after the flowers fade.
Light: Bright.
Temperature: Cool (45–65°F/7–18°C) during indoor growth period.
Fertilizer: None required, but a little liquid fertilizer added to water helps to support long-lasting flowers.
Water: After the bulbs begin to grow, water them lightly yet frequently to keep the soil lightly moist. When grown in water, only the roots should be suspended in water.
Soil: Any fast-draining potting soil; hyacinths can also be grown in water, pebbles, or glass marbles.
Repotting: If desired, shift growing bulbs to decorative containers when you bring them indoors in late winter.
Longevity: 6 months.
Propagation: Discard bulbs after they bloom. Buy new ones each fall.
Selections: Choose varieties based on color, such as pink ‘Anna Marie’, blue ‘Delft Blue’, or soft coral ‘Gipsy Queen’. Although less uniform, ‘Festival’ French-Roman hyacinths produce multiple flower spikes from each bulb.
Display tips: Enjoy the fragrance of hyacinths by keeping them in frequently used rooms during the day. To prolong flower life, move them to your coolest room at night.
FAMILY: LILIACEAE ORIGIN: JAPAN
THE PURE WHITE BLOSSOMS of Easter lilies signify the sacred side of spring, and they are among the most popular of all blooming house-plants. Yet they do not naturally bloom in spring, but rather in summer. Greenhouse growers coax them into bloom at exactly the right time by using elaborate temperature, light, and water regimens.
Easter lily (Lilium longiflorum)
To make sure that a purchased plant keeps its good looks for a long time indoors, choose one that shows only one or two partially opened buds. When you get the plant home, remove any plastic or foil wrapping that blocks the drainage holes (see “Fixing Floral Wrappings,”), water as needed to keep the pot moist, and keep the plant in a cool room where temperatures are 60–65°F/16–18°C, especially at night. When the blossoms open all the way, use a small pair of scissors to snip out the anthers, which prolongs flower life and prevents the scattering of pollen on furniture. After the blooms fade, Easter lilies can be planted outdoors, where they are hardy to Zone 5. Following a year of adjustment, they normally bloom in early summer when grown outdoors.
FAMILY: LILIACEAE ORIGIN: ASIA MINOR
THERE ARE MANY FORMS OF MUSCARI, all of which produce unusual rounded flower clusters on upright stems that resemble elongated bunches of grapes. Most bloom in shades of purple, and there are white forms, too. The flowers are very slightly fragrant; they often last a month when grown indoors under cool conditions.
Unlike other spring-flowering bulbs, grape hyacinths have a dual life cycle. A few grasslike leaves emerge soon after the bulbs are planted in fall, and more leaves appear with the flowers in spring. If planted outdoors after they have been forced for one season in a pot, the bulbs become dormant in summer. They then grow a thick tuft of leaves in the late summer which persists well into winter.
Grape hyacinth (Muscari armeniacum)
Follow the instructions in “Forcing Spring-Flowering Bulbs”, allowing a 10-week chilling period. White selections need 14 weeks of chilling. Flowers appear about 3 weeks after the pots are brought into warmer quarters. If you have no garden yourself, don’t hesitate to give your tired muscari to a friend who has a place to put them into the ground.
Light: Bright.
Temperature: Cool (40–65°F/4–18°C) during active growth period.
Fertilizer: Feed actively growing plants every 10 days with an all-purpose plant food.
Water: Water lightly yet often to keep soil a bit moist at all times.
Soil: Any potting soil that drains well, or a half-and-half mixture of potting soil and sand.
Repotting: Plant out in the garden after blossoms fade, setting bulbs 3 in/7.5 cm deep.
Longevity: 6 months to many years; these are excellent bulbs for naturalizing in the garden.
Propagation: Seldom needed. (Outdoors, very crowded clumps can be dug and divided in summer after the foliage fades.)
Selections: ‘Christmas Pearl’ requires less chilling than other varieties. ‘Valerie Finnis’ has refined pale lavender blooms.
Display tips: Tuck pots into a pretty basket and hide the containers from view with moss or pine needles. Purple muscari look great with dwarf yellow daffodils or white Easter lilies.
FAMILY: AMARYLLIDACEAE ORIGIN: SOUTHERN EUROPE AND ASIA
THE LARGE DAFFODILS that are commonly grown outdoors can be forced into bloom in pots, but smaller selections, such as those found within the N. cyclamenius species, often do a better job of holding their lovely heads high. They also feature backswept petals that suggest the presence of wind. Mature height is usually less than 12 in/30 cm, though height varies with variety. To grow them, follow the instructions in “Forcing Spring-Flowering Bulbs”, allowing 12 weeks of chilling. Expect the plants to bloom about 4 weeks after the containers are brought indoors. The flowering period lasts 2 to 3 weeks, so if you buy the plants in pots, choose specimens that have not yet begun to bloom.
Paperwhite narcissus (Narcissus jonquilla)
Paperwhite narcissus (Narcissus jonquilla, Tazetta type) are from warmer regions of Asia, and they need no chilling to promote bloom. Bulbs begin growing as soon as they are planted, with fragrant blossoms appearing after 3 weeks. Flowers last 2 to 3 weeks, so it’s important to purchase plants that are just beginning to bloom. Growing paperwhites sold in kits is a good introduction to the art of growing indoor bulbs.
Light: Bright.
Temperature: Cool (45–65°F/7–18°C) during the active growth period.
Fertilizer: Feed weekly with an all-purpose plant food when plants are growing.
Water: Keep soil moderately moist at all times.
Soil: Any potting soil, with pebbles added to improve drainage and add weight.
Repotting: Not necessary.
Longevity: 3 months for paper-whites, which are best discarded after they bloom. Miniature daffodils can be shifted to the garden, where they are likely to prosper for many years.
Propagation: Not needed.
Selections: Among little daffodils, yellow ‘February Gold’ is dependable in pots and often persists in the outdoor garden. ‘Jenny’ opens yellow and ripens to pure white. If you find the fragrance of paperwhites too musky for your taste, seek out ‘Grand Soleil d’Or’, which has a sweeter scent. Paper-whites often need staking to remain upright.
Display tips: Slip containers of yellow daffodils into small wicker baskets. With close attention to watering, paperwhites can be grown in damp pebbles in containers that lack drainage holes.
FAMILY: OXALIDACEAE ORIGIN: SOUTH AMERICA
THIS IS ONE OF THE EASIEST flowering houseplants to grow, often producing white or soft pink flowers continuously, except for a brief break in winter. The dainty flowers are held above the triangular, clover-like leaves. Oxalis plants do not require a period of dormancy, but if they are forced into one by dryness or an infestation of spider mites, you can cut off all the leaves, repot the bulblike pips, and have a healthy flowering plant in a matter of weeks.
Shamrock plant (Oxalis hybrid)
Oxalis is happy to grow in filtered sun indoors year-round, or you can move it outside to a shady patio or balcony in the summer. Good light intensifies the leaf colors with strains of burgundy or variegated leaves. Very hot, humid conditions may slow down the production of flowers, and low light levels in winter often lead to a short period of no flowers. Oxalis is sensitive to salt buildup in containers, but you can prevent damage to roots by flushing the pots thoroughly with plenty of clean, room-temperature water every 2 months.
FAMILY: LILACEAE ORIGIN: ASIA MINOR
OF ALL THE BLOOMING PLANTS you can grow indoors, tulips offer the widest range of color, and even carefully selected mail-order bulbs are quite inexpensive. You can force any type of tulip, but varieties that grow very tall or produce extremely large flowers often fall over when grown indoors. Triumph tulips seldom have these problems, so they are the favorite type for forcing.
Tulips (Tulipa hybrid)
Follow the instructions in “Forcing Spring-Flowering Bulbs”, allowing 14 weeks of chilling time. Deep containers help accommodate tulip bulbs’ extensive roots. When buying potted tulips in December and January, look for plants with buds that have not yet opened, and keep them in a cool, well-lighted room. Warmth makes potted tulips bloom very quickly, and also limits how long the flowers last. Even in a cool room, forced tulips usually hold their blossoms only 2 weeks. Large-flowered tulips that are forced to bloom indoors are best discarded after the flowers fade, but you may have luck transplanting smaller “species” tulips to your garden when the weather begins to warm in the spring.
Light: Bright.
Temperature: Cool (45–65°F/7–18°C) during active growth.
Fertilizer: None required, but a little liquid fertilizer added to water helps to support long-lasting flowers.
Water: Keep soil lightly moist while the plants are actively growing.
Soil: Any clean potting soil, with pebbles added to increase weight.
Repotting: If desired, shift growing bulbs to decorative containers when you bring them indoors. When tulip roots are too restricted, they may fail to flower well.
Longevity: 6 months for large-flowered tulips, which are best discarded after they bloom. (Small species tulips that are transplanted to the garden may persist for many years.)
Propagation: Not needed.
Selections: Triumph tulips are uniform and dependable, growing about 14 in/35 cm tall. Smaller, more long-lived species tulips, such as fragrant T. batalinii and T. humilis, grow to only 6 in/15 cm tall and make fine companions for other spring-flowering bulbs.
Display tips: Make the most of tulips’ formal demeanor by slipping the plants into ceramic or brass containers. To prolong flower life, move blooming tulips to your coolest room at night.
FAMILY: ARACEAE ORIGIN: SOUTH AFRICA
IN STORES AND FLORAL SHOPS, Easter lilies often share company with lovely potted calla lilies, which bear colorful, cupped, spade-shaped blossoms in pink, yellow, white, rust, and many bicolors. The flowers usually last 4 to 6 weeks, and many varieties also feature pretty speckled foliage. Callas grown outdoors often reach 36 in/90 cm in height, but those bred for container culture are usually 12 in/30 cm high and wide. Plants may be brought back into bloom in future seasons provided you give them a dry rest period in late summer. Allow the plants to dry until the leaves wither, clip off the old foliage, and keep the pots very lightly moist in a cool, shady spot. In winter, a fresh pot of soil, along with warmth, moisture, and bright light, will quickly bring them back to life.
Calla lily (Zantedeschia)
Light: Bright.
Temperature: Cool (60–75°F/16–24°C) in winter and spring, warming to moderate (70–85°F/21–29°C) from summer to fall.
Fertilizer: Feed plants every 3 weeks with a high-phosphorous plant food while the plants are actively growing.
Water: Keep soil lightly moist when rhizomes are just beginning to grow. Increase water as plants attain full growth so that roots stay constantly moist. Reduce water in late summer, allowing plants to dry almost completely while they are dormant.
Soil: Any good potting soil that drains well.
Repotting: In early summer, shift newly purchased plants to onesize-larger pots, disturbing roots as little as possible. In subsequent seasons, repot tubers in late fall, smooth side down, before coaxing them out of dormancy.
Longevity: 3 to 5 years.
Propagation: Unless you live in Zones 8 to 10, where callas can be grown outdoors as perennials, discard rhizomes that fail to produce a good show of flowers, and replace them with newly purchased plants or rhizomes. Pot-grown callas usually become weaker rather than stronger after several seasons.
Selections: Choose plants based on flower color and health. Most callas grown in containers are compact hybrids of Z. rehmanii.
Display tips: Clip off stems as flowers fade, and enjoy your calla as a foliage plant for 2 to 3 more months.
A GEOLOGIC DRAMA occurring slowly over a period of about 20 million years is credited for the emergence of cacti. Sixty million years ago, in the “before cactus” era, regions such as the American Southwest, central Mexico, and southern Brazil, now rich in cacti, enjoyed moist, tropical climates. As mountains pushed up, stopping the inflow of moisture, plants adapted to increasingly dry conditions by storing up water in their leaves and stems. Gradually leaves became spines, useful for protection from predators and as built-in sunscreens, and stems fattened into globes, columns, and other shapes designed to retain moisture. In the “after cactus” era (which began 40 million years ago), cacti became well established in numerous niches: on sandy ground, between rocks, and even growing on trees. Because most cacti produce flowers loaded with pollen that is spread from plant to plant by bees and other insects, cacti constantly cross-bred, resulting in thousands of diverse species.
The ghostly gray leaves of an Echeveria keep their calm cool year round, and the plants require very little care.
And so, though it is tempting to think of cacti as very primitive plants, the opposite is true. They are actually highly refined flowering perennials. Classification of cacti is incredibly complex and confusing, and even the most knowledgeable cactus experts sometimes have trouble identifying obscure species. The one characteristic that wins a plant a place in the Cactaceae family is the presence of areoles — the specialized buds from which spines and new bodies (stems) grow. In some genera, for example Echinopsis, the areoles are easily visible. In others they may be impossible to see unless you are a sharp-eyed botanist, but they are there.
All cacti are native to the Western Hemisphere. Succulents, which owe their existence to climate changes not quite as extreme as those that created cacti, are found on all continents, but most come from Africa, Asia, Europe, and Australia. Some succulents, such as living rocks (lithops), use their entire bodies to store moisture, but most have stems studded with juicy, water-retentive leaves. Sorting through the two groups is difficult enough without mixing them up, so they are listed separately in this chapter. The descriptive chart of nine easy-to-grow cacti on page 65 is followed by individual plant profiles. In similar fashion, eleven succulents are summarized in the page chart, followed by detailed profiles of each species. However, because cacti and succulents have similar cultural needs and share pest problems, general aspects of their care will be discussed together, and the Troubleshooting instructions covers both.
If you have a bright south window or other spot that gets strong sun for at least 4 hours a day, you have a good place to grow cacti and succulents. All cacti and succulents tolerate dry indoor air well, though they vary in how dry they like conditions to be. Species that come from jungle environments, such as the well-known Christmas cactus or the tiny succulents known as haworthias, demand regular watering, while desert cacti and agave are able to go weeks or months without any watering at all. Learn the preferences of each plant you adopt, not only in terms of water but in terms of rest period. Cacti are never fully dormant, but all of them need a rest period if they are to produce flowers. The same goes for many succulents — for example, kalanchoe. The timing and temperature of the rest period for various species are included in the plant profiles that follow. To fulfill the rest requirements of any cactus or succulent, appropriate changes in location are usually needed.
Cacti and succulents grown together in dish gardens are lovely, and some people grow their collection in a large tray that fills an entire windowsill. Arid dish gardens work well as long as the plants have similar seasonal needs. However, if cactus flowers are a high priority, it is often simpler to meet a plant’s needs for water, light, fertilizer, and temperature if it is kept in an individual pot. Cactus flowers last only 1 to 3 days, but the flowers are often gigantic compared to the size of the plants that bear them.
A columnar cereus cactus will grow slowly for decades with minimal care.
Cacti and succulents often show best if the surface of the soil is covered with small stones, gravel, or sand, so that it mimics a desert landscape. You can arrange a pebble mulch in a pattern by using two or three different colors to form an attractive design. The pots themselves can be plain terra cotta, or you can use more colorful ceramic or painted pots. Any container that provides excellent drainage will do for cacti and succulents.
Light: Most cacti and succulents are pleased to spend part of their time in baking sun, so they love spending the summer outdoors. Place them where they will get some direct sun but are sheltered from heavy rain. Cacti and succulents are indeed sun-loving plants, but they can get sunburn; to keep this from happening, gradually expose plants to increasing amounts of light. For example, if you plan to move a plant outdoors in summer, first shift it to a sunny west window for a few weeks in spring. After nights warm into the 60°F/16°C range, move the plant to a shady spot outdoors. After 2 weeks, it should be ready for partial sun. When kept outdoors in summer, most cacti and succulents are happiest with no more than 5 hours of direct sun; some grow best with only 2 or 3 hours. And, although some species may be fine in a very sunny spot, if you acclimate them to full sun it becomes more challenging to get them ready to come back indoors in the fall. This, too, should be a gradual process, in which the plants are moved as needed to slowly accustom them to reduced amounts of light. You also can keep your cacti and succulents indoors year-round. Bright light from a south or west window is needed in summer.
Summering outdoors, two agaves share quarters with a selection of other succulents. Many succulents propagate themselves so freely that they are often traded among friends.
Indoors in winter or outdoors in summer, the varied colors and textures of succulents make them ideal plants for displaying in groups.
Temperature: In winter, when most cacti and succulents prefer a cooler place to rest, a minimally heated room in which temperatures drop below 60°F/16°C at night is ideal. See the plant profiles for the temperature preferences of individual species. Some cacti must have a very cool resting place in winter if they are to set flowering buds.
Fertilizer: Cacti and succulents grow slowly, so they have less need for nitrogen than many other houseplants. The typical analysis of special cactus fertilizers is 2-7-7, which means they have a low concentration of all nutrients, particularly nitrogen. If you do not want to invest in a special fertilizer for one or two cacti but want to meet their special needs, use a high-phosphorous (low-nitrogen) fertilizer mixed at half the normal strength. Fertilize cacti and succulents only during their periods of active growth.
Many Mammillaria cacti sport a thick growth of fine hair, which protects them from hot sun.
Water: Overwatering in winter, when most cacti and succulents are at rest, is the most common reason for plant failure. Instead of soaking the roots, you might try spritzing water with a pump spray bottle, or dribbling small amounts from the tip of a thoroughly cleaned squirt bottle, like those used for dishwashing detergent. With clump-forming cacti and succulents, water only around the outside edge of the clump. Most cacti and succulents will begin to shrivel if they are underwatered, but they recover quickly when adequately hydrated. Rehydrate dried-out pots by watering the plant lightly two or three times. Cacti and succulents are prone to rot if their roots become soaking wet.
Most agaves have prickly spines, which limits their display to low-traffic areas.
A variety of cacti thrive in a broad, shallow container in potting soil amended with sharp sand or a specialty mix designed for cacti.
Cacti and succulents need more water in warm, sunny weather, their season of new growth. Again, it is better to water cacti lightly yet frequently than to give them too much water at once. In general, succulents need about twice as much water as cacti. However, leaves of succulents that form round rosettes often serve as funnels that collect water. This is okay once in a while, but try not to fill the rosettes with water more than once every few weeks, especially in winter.
Most cacti and succulents like low humidity, but extremely dry conditions can contribute to problems with spider mites. Mist resting plants from time to time, even if you do not water their roots. To a cactus or succulent, this is similar to being exposed to dew or fog, which for some species is a natural source of moisture. Jungle plants are especially appreciative of occasional misting when they are kept in places with very dry air.
Easter cacti (Hatiora hybrids) look similar to Christmas cacti, but they bloom and rest on a different schedule.
Soil: Cacti and succulents need a very fast-draining soil, since many of them evolved in areas that receive only 2 in/5 cm of rain each year. Regular potting soil with sharp sand or grit (rock crushed into .25 in/.6 cm-diameter pieces) added is fine, or you can buy potting soil specially made for cacti. Another option is to amend potting soil with perlite instead of sand. However, perlite is very light compared to sand or grit. In addition to improving drainage, sand or grit add weight to containers, which helps prevent toppling. When blending your own potting soil for cacti and succulents, mix 1 part sand, grit, or perlite to 2 parts potting soil. Adding a .5 in/1.25 cm layer of pebbles to the bottom of containers adds bottom weight and enhances drainage.
Repotting: Cacti and succulents should be repotted when they grow to within 5 in/1.25 cm of the edge of their container, or when they are so rootbound that they make little new growth. Some species, especially rat’s tail cactus and donkey tail, are very difficult to repot when the plant becomes large. If you can’t repot a large plant without damaging it, propagate it instead.
Most cacti and succulents grow well in broad, shallow containers. However, those that grow upright, or species with more extensive roots, may need deeper pots. You are less likely to overwater cacti grown in tight quarters, so it’s best to repot them into containers only slightly larger than the ones they have outgrown.
Although they last but a few days, cactus flowers feature rich colors and simple, refined forms.
There are safe ways to handle cacti when repotting so that neither you nor the plant suffer injuries. Before you begin, run a knife around the inside of the pot to make the cactus easier to remove. If the cactus is growing in a dish garden, use a knife to cut a circle around the plant about 1 in/2.5 cm beyond its outer edges. Next, wrap the cactus with a band made of strips of folded newspaper, held snugly with a gloved hand. Thick leather or rubber-coated gloves are best.
Place a layer of pebbles in the bottom of the new pot to improve drainage, and add 1–2 in/2.5–5 cm of potting soil. Make sure the soil mixture in the new container is lightly moist before replanting the cactus. Use a spray bottle to mist the roots as you set the cactus in place, and then mist the soil as you fill in around the edges with a long-handled spoon. Use a small brush to clean off any potting mix that became caught in the spines. Blow through a drinking straw to dislodge debris that will not brush away. Add a decorative mulch of pebbles or sand, and set the repotted plant in a bright yet sunless place for a few days. Wait about a week before you begin watering freshly repotted cacti.
Most succulents do not have spines, so they are easier to repot than cacti. With succulents, the biggest challenge is to handle the plants very gently, because succulent leaves often break off at the slightest touch. When repotting very delicate succulents, it can help to wrap them with a cloth throughout the operation.
Propagating: The easiest way to prolong the life of a beloved cactus or succulent is to propagate it from cuttings. Rooting is generally fastest at about 70°F/21°C, and cacti and succulents root best when they are entering their most active period of new growth. Late spring or early summer is usually the best time to propagate plants from rooted cuttings. When rooting either cacti or succulents, use a half-and-half mixture of peat moss and sand, a soilless mix used for seed starting, or cactus potting soil from a newly opened bag.
Many cacti are easily propagated by cutting away offsets that grow at the base of a parent plant. Allow the cut surface to dry into a callus for two days or more before transplanting it to a small container.
Most cacti develop pieces that are joined to the parent plant. Use a sharp, clean knife to sever a healthy young offset or pad from the parent plant, allow the cut end to dry and callus for a couple of days, and then plant it in a clean container filled with a half-and-half mixture of potting soil and sand. Keep it in a shady place, and water lightly every few days to keep the soil lightly moist. Expect roots to form in about a month, but wait another few weeks before repotting the plant into a permanent pot.
Cacti that do not show obvious places where they are joined to the parent plant also can be propagated from cuttings, though this involves cutting off the top of the plant. However, if a columnar cactus has developed black rot at its roots and is failing fast, severing its crown and setting it to root is usually the best alternative.
Many cactus collectors learn to graft plants, which is not difficult. It is also rather straightforward to start many cacti from seeds. However, both of these projects are best undertaken with the help of a good cactus book.
Succulents are among the easiest houseplants to propagate, since they typically develop offsets, or babies, which cluster around the parent plant. Others are very easy to root from stem cuttings. Again, the best season to propagate succulents is late spring or early summer, when plants are entering their period of most active growth. When propagating succulents, allow the severed offsets or cuttings to dry for at least a day before repotting them. The callus that forms over the cut section of the stem or root helps protect the plant from rotting when it is planted in an appropriate rooting medium.
The healing properties of fresh aloe gel seem almost magical, but a small mountain of scientific research explains how it helps minor burns disappear overnight. Aspirin-like salicylates soothe the pain, other enzymes reduce inflammation, and meanwhile additional chemical components increase blood flow to the injured area and kill a range of bacteria that might attempt to enter the wound.
After breaking off an aloe leaf to treat injured skin, can you propagate the tip to grow a new plant? Many have tried and all have failed, though it is sometimes possible to propagate aloe using the basal section of an outer leaf. The leaf can be a partial one, from which the tip has been harvested and the wound has dried into a callus, but it is essential that it include the curved “heel” that attaches to the main stem near the soil line. Set the leaf atop a small container filled with cactus potting soil, and use a small piece of wire to pin the base to the soil. Mist lightly from time to time to keep the leaf from drying out too quickly, but do not keep the leaf or the potting soil constantly wet. The cluster of new plantlets that forms along the lowest edge of the leaf will draw the moisture they need from the parent leaf. Until they develop roots, they have little use for water. When the plantlets are more than 1 in (2.5 cm) tall and the parent leaf has shriveled, cut it away and pot up the babies.
Small details: With cacti and many succulents, plant identification can be difficult. If you don’t know what species you have, use the chart to narrow the possibilities. Then check the plant profiles for more specific information. If you’re still stumped as to what plant you have, there are several sites on the Internet where you can look at pictures of various species, and others where you can post a picture of your cactus and get help identifying it from other cactus lovers. Try using “cactus identification” as a search phrase with your favorite search engine when seeking to identify a cactus. With succulents, you will get the best results by using the genus name, for example “Echeveria,” as the search word.
In the plant profiles that follow the charts, you will meet nine cactus species and eleven succulents that are popular houseplants. All are easy to grow, and many will produce exotic flowers when given the right regimen of care. But even without flowers, the symmetry of spines, well-defined shapes, and ease of care of cacti and succulents are reason enough to enjoy them as houseplants.
Echeverias are perhaps the most painterly succulents you can grow, and the symmetry of their leaves is often spellbinding.
Base of plant near the soil turns black.
CAUSE: Root rot, which spreads to the body of the plant.
REMEDY: Overwatering contributes to this problem, but it sometimes happens even when plants are properly watered. Poor air circulation can add to the problem. If possible, scrape away the black portions of the plant with a small serrated knife. Allow the callus to heal before watering the plant. In severe cases, propagate the plant from a healthy tip, offset, or stem cutting.
Plant appears shrunken and wrinkled.
CAUSE: Too little water.
REMEDY: Give the plant a light watering and mist it with a spray of water. Water again the following day, being careful not to drench the soil. Wait 3 days and water again; by then the plant should be plumped up nicely.
Brownish to gray patches on leaves; body of cactus appears yellowish.
CAUSE: Sunburn.
REMEDY: Move plant to a shadier spot. Make sure that plant is very gradually exposed to increasing amounts of sunshine.
Round to angular brown spots form on cactus and increase in numbers.
CAUSE: Corking, which can be caused by fungi, usually following a bruise or other physical injury.
REMEDY: Reduce water and fertilizer and increase air circulation around the plant. Overfeeding that leads to soft, succulent growth contributes to this problem.
Plant appears pale and pocked with tiny yellow specks.
CAUSE: Spider mites.
REMEDY: Isolate plant. Cacti: Clean by laying plant on its side and dousing the body with warm water. Succulents: Spray with warm water. When dry, spray plant with insecticidal soap. Dispose of badly infested plants.
White, woolly deposits on plant body or leaves.
CAUSE: Mealybugs.
REMEDY: Isolate plant, and remove as many mealybugs as possible with a toothpick. Lay plant on its side and spray with a neem-based insecticide or insecticidal soap. See page 272 for more information on this common house-plant pest.
Plant appears stunted; shows little if any new growth.
CAUSE: Root mealybugs.
REMEDY: Remove plant from pot and inspect roots for signs of light-colored, slow-moving insects that look like bits of mold. Rinse roots; spray with a neem-based insecticide. Repot plant in clean pot with fresh soil.
Brown disk-shaped insects attached to plants.
CAUSE: Scale, an occasional problem on cacti and succulents.
REMEDY: Isolate plant and remove scale with a toothpick. (On cacti, scale tend to cluster near the areoles, where spines emerge.) Repeat every few days until plant is clean.
Plant does not bloom.
CAUSE: Immature age; too little summer light in summer; insufficient winter rest.
REMEDY: Many species do not bloom until the plants are more than 3 years old. Acclimate plant to strong sunlight for several weeks in summer and keep it in your coolest well-lit room in winter. Use a high-phosphorous fertilizer. See plant profiles for species-specific details on improving bloom.
New growth is crooked or uneven.
CAUSE: Too little light, often combined with too much fertilizer.
REMEDY: Gradually move plant to brighter light. Remove misshapen parts if possible.
Flowers fade within 1 day.
CAUSE: Many cactus flowers are naturally short lived.
REMEDY: You can extend the life of blossoms on Christmas cactus and some other species by keeping them in a cool location, away from bright sunlight, when they are in bloom. Avoid moving cacti when they are in bloom.
Small, wedge-shaped insects are present on stem tips of succulents.
CAUSE: Aphids.
REMEDY: Clip off badly damaged stems. Use a fine spray of warm water to remove as many aphids as possible. Spray survivors with insecticidal soap. See page 269 for more information on managing this pest.
To help make plant identification simple, cacti and succulents are sorted into groups, with cacti summarized here and succulents appearing on page 76. Remember: Cacti have spines, while succulents seldom do. Succulents also have leaves, which are absent in cacti. Listed in alphabetical order by botanical name, the following nine species of cacti are popular and easy to grow.
Living stones (Lithops) fascinate their keepers with their curious life cycles.
Clockwise from top left: Aloe (Aloe barbadensis), crown cactus (Rebutia species), hen and chicks (Echeveria species) (both bottom photos)
FAMILY: CACTACEAE ORIGIN: MEXICO
A FAST GROWER, the stems of rat’s tail cactus can lengthen by 3 in/7.5 cm or more each year, eventually growing to 4 ft/1.2 m long. Showy flowers appear in spring and early summer. Though the flowers last only a few days, new ones continue to open for several weeks. They are most numerous on the previous year’s growth. A natural creeper adapted to growing in rocky ledges and trees, rat’s tail cactus develops little roots along the stems, making it easy to propagate. Stems of the original species have very shallow ridges, but numerous hybrids have dark green, deeply ridged stems. These large-flowered hybrids are less demanding of bright light and produce very large flowers in unusual colors including purple, pink, and bright orange. The ancestral species blooms violet-red.
Rat’s tail cactus (Aporocactus flagelliformis)
Light: In spring and summer, bright, or move to a half-shaded place outdoors. In fall and winter, bright light increases flowering in spring.
Temperature: In spring and summer, average room temperatures (65–75°F/18–24°C). In fall and winter, quite cool (50–55°F/10–13°C).
Fertilizer: Begin feeding in late winter with a cactus fertilizer or high-phosphorous fertilizer mixed at half the normal strength. Continue regular light feeding until late summer. Do not feed in fall and early winter.
Water: In spring to midsummer, water thoroughly, allowing soil to almost dry between waterings. In fall and winter, water less frequently, but do not allow soil to dry out completely. Dry stem tips are a symptom of insufficient water.
Soil: Cactus potting soil, or regular potting soil amended with sand.
Repotting: Repot young plants each year in midsummer. Older plants can be repotted less often.
Longevity: Many years if propagated from stem cuttings.
Propagation: Take 6 in/15 cm-long stem cuttings in early summer, allow the cut ends to dry for 2 days, and then set them to root in damp potting soil.
Selections: Buy plants in bloom if you want a certain color.
Display tips: This plant is most spectacular when grown in a hanging basket. The short spines are sharp and treacherous, so keep the plant well away from activity areas.
FAMILY: CACTACEAE ORIGIN: BRAZIL, URUGUAY, ARGENTINA
CEREUS CACTI OF THIS SPECIES include two very different forms often grown as houseplants. Most common are tall, columnar specimens, which are the mysterious night-blooming cereus. Only very old specimens bloom, but when they do the show is spectacular. Large white flowers to 6 in/15 cm long open at night and close the next morning. In the wild, the flowers give rise to edible red fruits that resemble apples. When kept as houseplants, these cacti are best appreciated for their upright form. They like to be moved outdoors in summer, an operation that must be undertaken carefully since the plants are quite heavy and well armored with tiny spines.
Peruvian apple cactus (Cereus peruviana)
A subspecies with a remarkably globular, convoluted form, Cereus peruvianus monstrosus stays smaller, growing to less than 24 in/60 cm tall. This is an excellent cactus for beginners. It seldom blooms, though very old plants may occasionally produce short-lived white flowers in summer. This clublike cactus resembles a green sculpture, and it is very long lived and dependable. Some forms are much more attractive than others.
FAMILY: CACTACEAE ORIGIN: SOUTH AMERICA
THE SEA URCHIN CACTUS lives up to its name by developing huge flowers on tubular stems, which emerge in clusters from the round cactus bodies in summer. Many species are similar, and some bloom only at night. Named hybrids that have been developed for strong flower production often bloom two or three times in the summer provided they enjoy a cool, dry rest period in the winter.
Sea urchin cactus (Echinopsis species)
There are hundreds of other species within the Echinopsis genus, which now includes cacti that were long known under other names, including Lobivia and Trichocerus. All share a need for cool, dry winters and a tendency to bloom at night. Some common “peanut” cacti are included in this group, and they are very easy to grow. To promote strong blooming, feed them regularly through summer and keep them cool through winter so they can set flower buds.
Light: From late spring to early fall, a half-shaded spot outdoors. In winter, bright light near a south or west window.
Temperature: From late spring to early fall, warm (70–80°F/21–27°C). In winter, cool (55–65°F/13–18°C).
Fertilizer: In spring and summer, feed plants monthly with a balanced fertilizer. In late fall and winter, do not feed.
Water: In spring and summer, water more often than other cacti, allowing soil to almost dry between waterings. In late fall and winter, keep plants very dry. Mist occasionally during winter rest period.
Soil: Cactus soil, or potting soil amended with sand.
Repotting: Repot when plants need more space, preferably in summer after flowers have faded. Pot up offsets after they grow to more than 1 in/2.5 cm in diameter.
Longevity: Many years if offsets are rooted every 3 to 4 years.
Propagation: Offsets; seeds.
Selections: The many named varieties vary in flower size and color. Orange-flowered ‘Paramount’ is a common parent, yet there are at least a dozen more available, some with contrasting midribs. All are beautiful.
Display tips: One of these cacti in full bloom forms a bouquet of exotic blossoms, which makes an awesome table centerpiece.
FAMILY: CACTACEAE ORIGIN: SOUTH AMERICA
THIS ATTENTION-GETTING CACTUS is really two cacti in one. The red top, a mutant form of Gymnocalycium that lacks chlorophyll but features bright red, orange, yellow, or pink color, is grafted onto a more vigorous green cactus. The green cactus feeds itself and the grafted top, and both gradually grow larger. After several years, red top may produce pink flowers in summer, provided the plant gets a cool rest in winter. Old, well-pleased plants also develop round offsets just above the graft union. The trickiest part of growing this cactus is getting the light right. The colorful cap can burn in bright sun, but the green part needs bright light in order to photosynthesize light energy for the whole plant.
Red top cactus (Gymnocalycium mihanovichii)
FAMILY: CACTACEAE ORIGIN: BRAZIL
EASTER CACTUS LOOKS VERY MUCH like the more popular Christmas cactus, but it blooms in spring rather than winter. A rain forest native, it adapts to less light than other cacti, and needs more water. Unlike Christmas cactus, this species is easily stressed by cool temperatures and should be brought indoors in early fall and kept in a bright room through winter. Allow it a cool, dry rest period after flowering stops in late spring, but otherwise treat Easter cactus like most of your foliage houseplants. Easter cactus is notorious for shedding its buds if it is moved during its flowering period. Locate the plant in a spot where it can stay put from late winter to late spring.
Easter cactus (Hatiora gaertneri)
Light: In summer, bright. In spring, fall, and winter, filtered indoor light.
Temperature: In summer, warm (70–80°F/21–27°C). In spring, fall, and winter, average room temperature (65–75°F/18–24°C).
Fertilizer: From early summer through fall, feed every 2 weeks with a cactus fertilizer, or a high-phosphorous fertilizer mixed at half the normal strength. In winter and spring, feed monthly.
Water: In spring, allow plants to dry out for a month after flowers fade. Through summer and early fall, keep soil lightly moist. In winter, allow soil to almost dry out between modest waterings. Shriveled stems indicate too little water.
Soil: Any good potting soil.
Repotting: Repot young plants annually in early summer. Older plants may be repotted every 2 to 3 years.
Longevity: To 6 years, or indefinitely when propagated from stem cuttings.
Propagation: Take stem cuttings consisting of two to three pads in summer, allow the cut ends to dry for a day, and then plant in moist potting soil. Keep in a shady place until new growth appears.
Selections: Buy plants in bloom to be sure of getting the color you want. Various shades of orange and pink are available.
Display tips: Grow in a hanging basket that can be suspended at eye level. Or, plant in a ceramic pot in a spring pastel color that coordinates nicely with the color of the blooms.
FAMILY: CACTACEAE ORIGIN: PRIMARILY MEXICO
THIS HUGE GENUS INCLUDES more than 250 species, which are often called “mamms” by devoted collectors. They are easy cacti for beginners, and so small that they work well in dish gardens. With mammillarias, the biggest problem may be identifying what you have, since species vary in shape and appearance. All are small, rarely growing more than 8 in/20 cm tall or wide, and they lack ribs. Instead, tufts of spines emerge from raised knobs, called tubercules, which are arranged in symmetrical patterns and are densely crowded near the crown. Mammillarias flower at a young age, and the flowers, which are borne from creases between the tubercules, usually appear in a circular, wreathlike pattern.
Powder puff (Mammillaria species)
To encourage blooms, which appear in late spring or summer, keep plants cooler in winter than in summer. Most species are hardy to 32°F/0°C, but it’s best to keep them above 50°F/10°C. Dry winter conditions help flower buds to form. These cacti enjoy warm temperatures in summer, though they should be kept in a spot where strong summer sun is limited to 4 hours each day.
Light: Direct sun 4 hours daily, or bright light all day, year-round.
Temperature: From late spring to early fall, warm (70–85°F/21–29°C). In winter, cool (50–65°F/10–18°C).
Fertilizer: In spring and summer, feed monthly with a cactus fertilizer, or a high-phosphorous plant food mixed at half the normal strength. In fall and winter, do not feed.
Water: Allow soil to become almost dry between waterings. In hot summer weather, plants may need water twice weekly. Water very sparingly in winter.
Soil: Cactus soil, or potting soil amended with one-third sand.
Repotting: When grown in broad, shallow containers or dish gardens, plants need repotting only every 2 to 3 years.
Longevity: Many years.
Propagation: Offsets; seeds.
Selections: Puffy white hairs cover the ball-shaped powder puff or snowball cactus (M. bocasana). Golden star or lady fingers (M. elongata) is fast and easy to grow. Many other species are available.
Display tips: Grow in shallow containers weighted with gravel in the bottom. Mammillarias are wonderful subjects for indoor windowboxes that include a variety of small cacti.
FAMILY: CACTACEAE ORIGIN: SOUTH AMERICA
FOR 60 YEARS, THESE SHOWY LITTLE GLOBES were called Notocactus, and many catalogs (and plant tags) still use that genus name. Now renamed Parodias, there are 100 species, several of which make excellent houseplants. Old favorites like silver ball cactus (P. scopa) are easy to grow, bloom willingly, and adapt well to life in homes and offices. Most parodias are round and ribbed, grow to less than 10 in/25 cm tall, and often feature showy spines arranged in a symmetrical matrix pattern. After several years, some ball cacti produce small offsets near the base. Flowers appear near the crown, and may be yellow, orange, pink, or red, depending on the species.
Ball cactus (Parodia nivosa)
In their native habitat, parodias receive warm rain often in summer and experience dry, temperate winters. If you mimic this pattern, your parodias should do well. Ball cacti thrive when allowed to spend the summer outdoors in a half-shaded spot.
Light: From late spring to early fall, partial shade outdoors. In winter, bright light from a south or west window.
Temperature: From late spring to early fall, warm (65–85°F/18–29°C). In winter, cool (55–65°F/13–18°C).
Fertilizer: From late spring to late summer, feed monthly with a balanced liquid fertilizer. In fall and winter, do not feed.
Water: From late spring to early fall, water as often as needed to keep soil lightly moist. In winter, allow soil to become almost dry between waterings.
Soil: A very sandy yet humus-rich mix, such as cactus soil amended with a small amount of sand.
Repotting: Repot only when the plants reach the edge of the pots, usually only every 2 to 3 years.
Longevity: Many years.
Propagation: Seeds; offsets.
Selections: Silver ball cactus (P. scopa) is widely available and easy to grow. It features showy white hairs in tufts at the spines, and yellow to yellow-orange flowers. Yellow tower cactus (P. leninghausii) elongates as it grows, and is well armed with long yellow spines. Fast-growing Tom Thumb cactus (P. mammulosa) has a barrel shape, and often blooms repeatedly in summer.
Display tips: Place ball cactus on a low table where the patterns formed by ribs and spines can be easily seen. Combine young plants with other cacti and succulents in small dish gardens.
FAMILY: CACTACEAE ORIGIN: ARGENTINA
NATIVE TO HIGH ELEVATIONS of the South American Andes, these small cacti bloom willingly in spring and summer provided they are given a cool, 3-month-long winter rest. Flower buds develop near the base of the plant or in crevices between the mother plant and its offsets. Plants with many offsets may produce a dozen tubular blossoms, which may be white, pink, yellow, orange, or red, depending on the species.
Crown cactus (Rebutia species)
Rebutias may be sold as individual plants or included in dish gardens. Once a plant grows into a flattened head about 2.5 in/6.25 cm across and 1.5 in/3.75 cm tall, it begins propagating itself into a cluster. With good care, a clump up to 6 in/15 cm across will develop within 3 to 4 years. In summer, carefully remove offsets with a gentle twist and transplant them to individual containers or a new dish garden.
Light: From spring through fall, bright light. In winter, rest in moderate light.
Temperature: From spring through fall, average room temperature (65–75°F/18–24°C). In winter, rest in a cool room (50–65°F/10–18°C).
Fertilizer: Feed once in spring, and a second time in late summer, with a balanced liquid plant food.
Water: From spring through fall, allow soil to become nearly dry between waterings, but do water regularly. In winter, water lightly only every 7 to 10 days.
Soil: Cactus potting soil, or regular potting soil amended with grit or sand.
Repotting: Every other summer, or as needed to provide room for new offsets.
Longevity: Many years due to ease of propagation. Discard old plants when they lose color and lack vigor, which is often due to root rot.
Propagation: Offsets; seeds.
Selections: These cacti may be labeled by species name, or you may get a mystery rebutia in a dish garden. Of more than 40 species grown by collectors, the redblooming R. minuscula is famous for producing large red flowers at a young age.
Display tips: Individual plants look great in a dish garden, but a large cluster, set in a shallow pot, becomes spellbinding when it is in bloom. In good years, blooms of some species are so numerous that they nearly cover the plants.
FAMILY: CACTACEAE ORIGIN: BRAZIL
THESE HEAVY-BLOOMING RAIN FOREST NATIVES are easy to grow, and they are available in a huge range of colors. The intensity of bloom depends on climactic factors: bright light in summer and fall, combined with days that gradually become shorter and cooler. It is therefore ideal to move plants outdoors in summer, and keep them there until night temperatures dip down to 40–50°F/4–10°C. When you bring them in, keep them in a cool room that stays completely dark after sunset. Buds will develop in early winter, at which time plants should be moved to where you want them to bloom. Once plants begin blooming, they may drop their blossoms if exposed to any type of stress. This is why plants that are bought in bloom often shed their buds and blossoms. With less shifting about after buds form, plants that shed their buds one winter will bloom beautifully the following year.
Christmas cactus (Schlumbergera hybrid)
Light: From late spring to fall, bright. From late winter to early spring, rest in moderate light.
Temperature: From late spring to late summer, warm (65–80°F/18–27°C). In fall and winter, cool (50–65°F/10–18°C).
Fertilizer: From spring through summer, feed every 2 weeks with a balanced fertilizer, mixed at a slightly reduced rate, or use a high-phosphorous plant food. In fall and winter, feed monthly.
Water: From spring through fall, keep soil lightly moist. In winter, allow soil to almost dry out between modest waterings. Shriveled stems indicate too little water.
Soil: Any good potting soil.
Repotting: Repot young plants annually in early summer. Older plants may be repotted every 2 to 3 years.
Longevity: 5 to 6 years, or indefinitely when propagated from stem cuttings.
Propagation: Take stem cuttings consisting of two to three pads in early summer, allow the cut ends to dry for a day, and then plant in moist potting soil. Keep in a shady place until new growth appears.
Selections: Buy plants in bloom to be sure of getting the color you want. Light pink and lilac shades are especially beautiful.
Display tips: Grow this cactus in a broad pot that can be placed on a tabletop when it blooms. Christmas cacti also are easy to grow in hanging baskets.
Listed in alphabetical order by botanical name, these eleven species of succulents are popular and easy to grow.
FAMILY: AGAVACEAE ORIGIN: NORTH AMERICA TO MEXICO
MORE THAN 450 SPECIES OF AGAVE have been identified, and several make excellent houseplants provided you can give them abundant natural light. This is easy in summer, when agaves love to be moved outdoors, but they need bright light in winter, too. The easiest agaves to keep indoors are small ones, such as little princess agave (A. parviflora) and A. victoriae-reginae, both of which grow into 10 in/25 cm, ball-shaped plants packed with spiny leaves. Many people love the widely spread, wavy leaves of variegated American agave, which grows so slowly that it can be kept as a houseplant for about 10 years. After that, it must be set free in a garden, where it is hardy to about 15°F/-9°C. Only garden-grown or wild agaves produce flowers, so don’t look for blooms on indoor plants. The sap of all agaves can cause skin irritation, so be careful when handling.
Agave (Agave parryi)
Light: From late spring to early fall, direct sun at least 5 hours a day. In winter, keep in a bright south window, where temperatures cool off at night.
Temperature: From late spring to fall, very warm (70–90°F/21–32°C). In winter, cool (50–60°F/10–16°C).
Fertilizer: In spring and summer, feed monthly with a balanced houseplant fertilizer. In fall and winter, do not feed.
Water: In spring and summer, use warm water, and water plants before the soil becomes completely dry. In fall and winter, provide only scant moisture.
Soil: Regular potting soil amended with pebbles or sand to improve drainage.
Repotting: Repot only every few years, to refresh the soil. These plants are slow growers, and are best handled as little as possible.
Longevity: 10 to 40 years, depending on species. When grown in open soil in warm, arid climates, plants often live for 50 years or much longer.
Propagation: Seeds, offsets. Agaves grown as houseplants seldom need to be propagated, which is best done in a greenhouse.
Selections: Named varieties of A. victoriae-reginae require a little less light than other agaves, so they are often the best choice if you live in a cool or cloudy climate.
Display tips: Grow agaves in a stout, heavy pot with a wide bottom, because plants are prone to toppling if planted in small, lightweight containers.
FAMILY: ALOACEAE ORIGIN: NORTHERN AFRICA
IT IS NO WIVES’ TALE that the sap of the aloe plant cures minor burns and other skin problems. It really works. The most medicinally potent species is pretty, too, with plump, elongated leaves that fan out from a central base. Aloe is easy to grow, and can be kept indoors year-round or moved outside in the summer. Just be sure to make moves gradual ones. Aloe sunburns easily when moved from low indoor light to bright sun too quickly, and the plants sulk when moved from a warm, sunny porch to a dim room. When grown outdoors in mild winter climates, aloe often blooms in late winter or spring. Aloe rarely blooms when grown indoors.
Burn Plant (Aloe barbadensis)
FAMILY: CRASSULAEAE ORIGIN: SOUTHERN AFRICA
THE TREELIKE FORM AND SHINY LEAVES set the jade plant apart from other succulents, and it is easy to grow in homes and offices. When grown outdoors in frost-free areas, jade plants grow into 4 ft/1.2m-tall shrubs. Indoors, they seldom grow more than 24 in/60 cm tall over a period of many years. Plants more than 10 years old may flower in winter, though blooming is uncommon in indoor-grown plants. Purchased plants often consist of up to five cuttings that have been rooted and grown in a single pot, which allows little room for growth. Divide crowded pots in spring, transplanting each plant to an individual container, or keep them in groups of no more than three plants in a 6 in/15 cm pot. Plenty of light and fertilizer improves the leaf color of jade plant.
Jade plant (Crassula ovata)
FAMILY: CRASSULACEAE ORIGIN: SOUTHWESTERN NORTH AMERICA THROUGH MEXICO
SEVERAL PLANTS GO BY THE COMMON NAME of hen and chicks, and it can be difficult to tell them apart. Echeverias differ from semperivums (which are hardier plants, often called houseleeks), in that echeverias have thicker, more succulent leaves and much less tolerance of cold weather. Echeverias grow into symmetrical rosettes held on short stems that may be 2–6 in/5–15 cm across, depending on cultivar. They often bloom in spring, but many growers pinch off the blooms to preserve the appearance of the rosettes. Echeverias are easy to grow and willingly produce offsets, known as chicks, that can be transplanted to new pots with no complications. Many varieties are blushed with red, which becomes more intense when the plants receive good light. Plants may be moved outdoors in summer or kept in a home or office year-round. As long as they get plenty of light, echeverias are very happy houseplants.
Hen and chicks (Echeveria species)
Light: Bright light year-round, with some direct sun in summer.
Temperature: From spring to late summer, average to warm (65–80°F/18–27°C). In fall and winter, cool to average (55–75°F/13–24°C).
Fertilizer: From spring through fall, feed plants every 2 weeks with a high-phosphorous plant food mixed at half the normal strength. In winter, feed monthly.
Water: Provide water as often as needed to keep the soil lightly moist. Plants that dry very quickly in summer may need repotting. Water less in winter.
Soil: Cactus potting soil, or regular potting soil amended with one-fourth part sand.
Repotting: Repot every 2 years, or more often if plants outgrow their pots.
Longevity: Indefinitely, due to this plant’s ease of propagation.
Propagation: Remove offsets with a short stub of stem attached, and transplant them to new containers. Small offsets transplant more easily than large ones.
Selections: Choose plants based on their appearance, which varies between the red-blushed green leaves of ‘Painted Lady’ to the woolly felted rosettes of ‘Doris Taylor’ to some with frilled red edges, such as ‘Wavy Curls’. Most named varieties are interspecies hybrids.
Display tips: Grow several different echeverias together in a broad bowl kept on a sunny windowsill. They also mix quite well with other succulents.
FAMILY: AIZOACEAE ORIGIN: SOUTH AFRICA
THIS INTERESTING SMALL SUCCULENT grows to only 6 in/15 cm tall, but the short green or orange-blushed leaves, often speckled with white dots, provide ongoing drama. The edges of each short, triangular leaf bear incurved, soft spines that resemble teeth. The teeth interlock on young leaves, but as the leaves grow, they open until they look like dangerous jaws. Tiger’s jaws gradually grows into a clump of ground-hugging stemless rosettes. Sometimes yellow flowers appear in fall, but only on mature plants that get at least 4 hours of strong sun each day all summer. This plant likes warm to hot conditions during its active growth period, so consider moving it outdoors in summer. In winter, do not allow the plant to be chilled by temperatures below 60°F/16°C.
Tiger’s jaws (Faucaria tigrina)
FAMILY: ASPHODELACEAE ORIGIN: SOUTH AFRICA
COLLECTING HAWORTHIAS QUICKLY BECOMES ADDICTIVE to plant lovers who delight in small things, because haworthias are the smallest succulents of them all. Many grow less than 3 in/7.5 cm tall or wide, while some columnar types may grow to 5 in/12.5 cm tall. This genus includes more than 80 species that offer endless variation in form. Many resemble miniature aloes, a few look like tiny echeverias, and some are sedum look-alikes. They have in common a tremendous tolerance for neglect, needing only sun and occasional water to prosper for many years. A collection of several haworthias can be grown in an 8 in/20 cm-wide shallow dish kept in a sunny window. It is important to repot them every year or two. Haworthias shed some of their old roots each spring, so refreshing the soil is necessary maintenance for healthy plants.
Haworthia (Haworthia species)
FAMILY: CRASSULACEAE ORIGIN: MADAGASCAR
IN THE MIDDLE OF WINTER, it’s hard to resist a kalanchoe covered with clusters of red, pink, or orange flowers. The flowers last several weeks, and the plants are quite easy to grow. However, before a kalanchoe will make buds, it must be exposed to a series of long, sunny days followed by at least 2 weeks of short days, less than 12 hours long. This is easy enough to accomplish by placing plants outdoors in summer and then bringing them indoors in late fall, just before nighttime temperatures drop below about 40°F/4°C. After you bring the plant in, keep it in a room where no lights are used at night. When brought into bloom naturally, kalanchoes flower in January and February. To speed up the schedule, cover the plants with a box for 14 hours each night for 14 consecutive days in early fall, and let them have moderate light during the day. Blooms will appear about 6 weeks later. Snip off bloom-bearing branches after the flowers fade to preserve the handsome good looks of this plant.
Kalanchoe (Kalanchoe blossfeldiana hybrid)
Light: Bright direct sunlight indoors; filtered shade outdoors.
Temperature: From late spring to early fall, warm to very warm (70–90°F/21–32°C). In fall and winter, cool to average (50–70°F/10–21°C).
Fertilizer: From late spring to midwinter, feed with an all-purpose houseplant food monthly. From late winter to early spring, do not feed.
Water: From spring to fall, keep the soil lightly moist. In winter, allow the soil to dry out between light waterings.
Soil: Any good potting soil.
Repotting: Repot annually in early summer.
Longevity: 2 to 3 years, or indefinitely when propagated from stem cuttings.
Propagation: When plants are more than 2 years old, take stem cuttings and set them to root in small pots in late spring (see page 299).
Selections: In addition to flowering kalanchoe, other interesting species include devil’s backbone (K. diagremontiana), which is also known as “mother of thousands” because of the way it produces tiny, rooted plantlets along its leaf margins. Panda plant or pussy ears (K. tomentosa) features thick gray-green felted leaves with reddish markings.
Display tips: To celebrate the blooming of flowering kalanchoe, wrap the pot with colorful cloth or paper, tied with ribbon or raffia.
FAMILY: AIZOACEAE (FORMERLY MESAMBRYANTHEMACEAE) ORIGIN: SOUTHERN AFRICA
THERE IS LITTLE ARGUMENT that living rocks are the most unusual succulents in the world. They were not discovered until 1811, when a plant collector noticed that some of the stones underfoot were not stones at all, but living succulent plants.
Living stones (Lithops species)
Lithops are not difficult to grow provided you follow their natural growth cycle. In late winter and spring, new leaves push up through the cleft between the bodies. The new leaves take up the moisture and nutrients in the old leaves, so the plants need no water during this time. Do water them a few times in late spring, after the old leaves have shriveled away. Then allow the plants to become quite dry through summer. In fall, flower buds may emerge from the cleft provided the plants are fully mature. This is a good time to water the plants lightly for several weeks. Then let them rest again through winter, until the life cycle begins anew.
Light: In summer, 4 hours of direct sun. From fall through spring, less light, by an east or south window.
Temperature: In summer, warm to very warm temperatures (70–90°F/21–32°C). From fall through spring, cool to average room temperatures (55–70°F/13–21°C).
Fertilizer: Twice yearly, once in spring and once in fall, feed plants with a balanced, all-purpose houseplant food.
Water: Lithops have two seasons when they need light watering: in spring after new leaves have absorbed old ones, and in fall when flowers appear. At other times, keep plants very dry, watering lightly only if plants become badly wrinkled.
Soil: Cactus soil amended with sand.
Repotting: Repot only when plants outgrow containers, usually only every 5 years or so. Use 5 in/12.5 cm-deep pots to accommodate taproots. Set plants so that one-third of the leaves are buried.
Longevity: Many years.
Propagation: Seeds; division of old plants that have grown into large clusters.
Selections: Plants vary in color, and are sold by species name. L. aucampiae has sandy brown bodies with reddish markings, and blooms yellow. L. marmorata has gray to beige bodies with white, fragrant flowers. There are many others.
Display tips: Grow two or three different species in a broad pot, with an attractive arrangement of smooth stones to keep them company.
FAMILY: AGAVACEAE ORIGIN: TROPICAL AFRICA
ONE OF THE MOST CAREFREE HOUSEPLANTS you can grow, sanseveria adapts quickly to life in homes, workplaces, and shopping malls. Often described as indestructible, sanseveria tolerates neglect but responds to good care by growing sturdy, sword-shaped leaves, which often are edged with yellow or white. Clean them periodically with a damp cloth to maintain a glossy sheen. Very old plants sometimes produce clusters of white flowers in winter, but most indoor-grown plants go many years between bloom cycles. This is a top houseplant for beginners, but seasoned houseplant growers also love sanseveria for its stalwart constitution and dramatic upright form.
Mother-in-law’s tongue (Sanseveria trifasciata ‘Laurentii’)
FAMILY: CRASSULACEAE ORIGIN: MEXICO
NUMEROUS HARDY SEDUMS GROW in outdoor rock gardens, and several of these make good houseplants, too. The sedum known as donkey tail is too delicate for outdoors, but it makes an attractive and interesting indoor companion. Stems that emerge from the plant’s crown are thickly clad with juicy, gray-green leaves, which overlap like the coarse hair on a donkey’s tail. Plants that enjoy bright light in summer and a cool winter rest sometimes produce small pink flowers at the stem tips in summer. This plant’s biggest weakness is its fragile leaves; a slight bump can send them falling to the floor. However, new stems constantly emerge to replace such casualties.
Donkey tail (Sedum morganianum ‘Burrito’)
Light: Bright light most of the year. Extra light in summer is beneficial, but be careful, because indoor-grown plants sunburn easily.
Temperature: Average room temperatures (65–75°F/18–24°C). A cool winter rest, with 55–60°F/13–16°C temperatures, increases the likelihood of blooming.
Fertilizer: From spring to late summer, feed monthly with an all-purpose balanced houseplant food. In fall and winter, do not feed.
Water: From spring through summer, water as often as needed to keep soil lightly moist. In fall and winter, allow soil to become dry between waterings.
Soil: Cactus potting soil.
Repotting: Repot as needed in spring every 2 years if plant is actively growing. After plants fill an 8 in/20 cm pot, they become so fragile that repotting is difficult. Begin propagating tip cuttings when repotting becomes impractical.
Longevity: 5 to 10 years, or indefinitely if propagated from stem tip cuttings.
Propagation: Take a 3 in/7.5cm-long tip and remove leaves from the lowest 2 in/5 cm section. Insert the stem in a half-and-half mixture of damp peat moss and sand, and keep it moist for 2 months.
Selections: This plant is usually sold by species name. One unusual cultivar, ‘Burrito’, features short, stocky stems thickly covered with blunt leaves. It is a little less fragile than other donkey tails.
Display tips: Grow in a hanging basket or suspended pot, so that the long stems can trail down over the edges. The gray-green leaves show especially well when this plant is grown in a dark-colored container.
FAMILY: ASTERACEAE ORIGIN: SOUTHERN AFRICA
NO OTHER PLANT looks like string of pearls, with succulent leaves that grow into small, round marbles, .5 in/1.25 cm in diameter. Although dainty in appearance, string of pearls is a robust grower, quickly covering the surface of its container and then developing stems that hang over the sides of the pot. Plants grow only a few inches tall, but the trailing stems can extend 24 in/60 cm or more if they are not accidentally broken off. Mature plants that enjoy a cool rest in winter sometimes produce small white flowers, which are not showy but carry a faint cinnamon scent. If long stems become straggly, snip them off and propagate new plants from healthy stem sections.
String of pearls (Senecio rowleyanus)
Light: 2 to 4 hours of direct sunlight year-round.
Temperature: From spring to fall, warm (70–80°F/21–27°C). In winter, cool (55–60°F/13–16°C).
Fertilizer: From spring through fall, feed every 2 weeks with a balanced liquid fertilizer mixed at half the normal strength. In winter, feed every 6 weeks.
Water: From spring through fall, keep soil lightly moist. In winter, allow soil to dry out between waterings. Beads flatten if the plant is underwatered, but this plant requires slightly less water than other succulents.
Soil: Cactus potting soil, or regular potting soil amended with one-third part sand.
Repotting: Repot annually in spring, or every 2 years if the growth of mature plants is so thick that it would be ruined by repotting. Propagate cuttings every few years, because older plants tend to decline.
Longevity: Up to 5 years, or indefinitely if propagated from stem cuttings.
Propagation: In early summer, take 4 in/10 cm-long stem cuttings, and press them into damp potting soil until the beads are almost covered. Keep lightly moist. New roots form quickly from the places where the beads join the stem.
Selections: A variegated form, in which the beads are sprinkled with yellow spots, is sometimes seen, but this plant is usually sold by its common name.
Display tips: Grow in a hanging basket, or in a broad dish so that the stems form a thick green groundcover over the surface.
FAMILY: RUTACEAE ORIGIN: CHINA
IF YOU HAVE SUFFICIENT ROOM inside a sunny, south-facing window for a 36 in/90 cm-tall plant, that plant should be calamondin orange or another small citrus fruit, such as ‘Meyer’ lemon. Both are easy to grow and can be counted upon to bear tart fruit almost year-round, beginning in their second year. The leaves give off a refreshing citrus scent when crushed, and the flowers are lightly fragrant as well.
Calamondin orange (Citrus × citrofortunella mitis)
The calamondin orange is a superior houseplant. A strong producer of 1 in/2.5 cm-wide, bright orange fruits, calamondin orange is actually a cross between a kumquat and an orange. The tart fruits can be used like lemons in cooking or can be made into marmalade. Taste them for bitterness first. If the rinds are very bitter, supplement the recipe with rinds from milder-flavored oranges. There is no rush to pick calamondins, as they remain in prime condition on the plants for several weeks. Young plants are available by mail, or you can grow one from a cutting taken from a friend’s plant. As a precaution against citrus canker and various plant viruses, live citrus plants cannot be shipped to Arizona, California, Florida, or Texas. Shop for plants locally if you live in one of these states.
Light: Direct sun at least 4 hours a day year-round.
Temperature: Average room temperatures (65–75°F/18–24°C) year-round are ideal, though plants can accept cool (60°F/16°C) conditions in winter, and warmer (80°F/27°C) temperatures in summer.
Fertilizer: In spring and summer, feed plant every 2 weeks with a balanced plant food that includes micronutrients. In fall and winter, fertilize monthly.
Water: In spring and summer, keep soil lightly moist at all times. In fall and winter, allow the top inch of soil to dry between waterings. Mist plant twice weekly to increase humidity.
Soil: Any good potting soil.
Repotting: Repot young plants every 2 years. When 3- to 4-year-old plants fill an 8 in/20 cm pot, repot only every 2 to 3 years.
Longevity: 10 years or more.
Propagation: Root 4 in/10 cm-long stem tip cuttings in early summer (see page 299). Use rooting powder, and keep cuttings enclosed in a plastic bag to maintain high humidity. Cuttings root in 6 to 8 weeks.
Selections: When shopping for calamondin orange, buy from a reputable supplier to be sure you get cutting-grown plants. Many citrus fruits grow easily from seed, but they seldom fruit well. Very inexpensive plants are probably random seedlings that mature into substandard houseplants.
Display tips: To ensure good fruit set, dab flowers with a dry paintbrush to distribute pollen among the flowers.
Plant does not bloom.
CAUSE: Pot is too large; plant is overfertilized.
REMEDY: Keep young plants in pots no larger than 6 in/15 cm across. Reduce fertilizer, or switch to a cactus fertilizer or high-phosphorous plant food.
Flowers drop without setting fruit.
CAUSE: Very dry air.
REMEDY: Keep a humidifier running in the room when flowers appear, or mist plant daily first thing in the morning. Do not mist when the sun is shining brightly, as leaf damage can occur.
Plant grows leggy, fruit causes branches to droop.
CAUSE: Needs pruning.
REMEDY: Keep older plants compact by pruning back long branches in spring. New branches will emerge from just below where older ones are tipped back.
Brown disc-shaped insects on leaves and stems.
CAUSE: Scale.
REMEDY: Several types of scale infest citrus fruits. On houseplant citrus, manage this pest by hand by removing them with your fingernail or a toothpick. Painting the scales with a cotton swab dipped in vegetable oil makes them easier to remove.
FAMILY: GESNERIACEAE ORIGIN: CENTRAL AND SOUTH AMERICA
A VINING COUSIN TO AFRICAN VIOLETS, columnea is often called “goldfish plant” because of its curved tubular blossoms, which resemble leaping fish. Well-grown mature plants flower heavily in spring and summer, often producing dozens of blossoms at a time. Expect little or no blooming in winter when light levels are low. Maintaining somewhat dry soil in winter also promotes heavy spring flowering, but take care that the soil never dries out completely. In the wild, columnea grows in trees in shady tropical rain forests.
Goldfish plant (Columnea gloriosa)
Columnea stems may grow to 36 in/90 cm long, but it is best to pinch them back to 18 in/45 cm or less, which encourages bushy growth. The arching stems typically rise 12 in/30 cm above the pot before cascading downward, so this is an ideal plant for a hanging basket. Some varieties have hairy leaves, while others feature glossy foliage. In winter, avoid wetting the leaves of either type when watering, as this can lead to problems with stem rot. Keep plant indoors in summer, as high temperatures or too much light can cause leaves to turn brown.
Light: Moderate light from an east window, or fluorescent light.
Soil: Average room temperatures (65–75°F/18–24°C) year-round.
Fertilizer: From spring through summer, feed every 2 weeks with a high-phosphorous plant food mixed at half the recommended rate. In winter, feed monthly.
Water: From spring through summer, provide tepid water as often as needed to keep soil lightly moist. In winter, allow soil to become almost dry between waterings. Maintain moderate to high humidity year-round by misting plant daily or using a humidifier.
Soil: A light, porous mix such as African violet soil.
Repotting: Every 2 to 3 years, preferably in spring. Lightly prune roots of mature plants when repotting them rather than moving them into very large containers.
Longevity: 4 to 5 years, or indefinitely when propagated from stem tip cuttings.
Propagation: In spring or summer, root 3 in/7.5 cm-long, nonflowering stem tip cuttings as described on page 299. Newly rooted cuttings need to grow for at least a year before they begin blooming.
Selections: There are many named hybrids, which vary in leaf and flower color. Red-flowered ‘Firebird’ and ‘Aladdin’s Lamp’ have dark green foliage, while ‘California Gold’, with yellow flowers edged with red, has bronzy green leaves. The red flowers of ‘Light Prince’ look dazzling among its white variegated foliage.
Display tips: Goldfish plant is always at its best when grown in a hanging basket.
Leaf tips turn brown.
CAUSE: Buildup of calcium in the soil.
REMEDY: Leach pots as described on page 263 monthly in summer. Use rainwater or distilled water whenever possible; avoid using a fertilizer that contains high amounts of calcium.
Leaves drop.
CAUSE: Cold conditions or very dry air.
REMEDY: Keep plant away from cold windows, as it is sensitive to chilling injury. Mist plant daily, especially in winter, or keep it in a room with a humidifier.
Stems wither and die.
CAUSE: Stem or root rot, caused by fungi in the soil.
REMEDY: Prune away damaged stem at soil line. Allow soil to dry out between waterings. Propagate stem tip cuttings from healthy stems, and pot them in fresh potting soil in clean pots. When cuttings show new growth, discard parent plant.
Leaves appear parched, with faint webbing on leaf undersides.
CAUSE: Spider mites.
REMEDY: Isolate plant, and prune off badly infested branches. Wipe leaf undersides with a soft cloth dipped in soapy water, and mist plant daily for a week. See page 274 for more information about this pest. Badly infested plants that do not quickly recover should be discarded.
White cottony deposits on stems.
CAUSE: Mealybugs.
REMEDY: Isolate plant, and pick off mealybugs with tweezers or a cotton swab dipped in alcohol. Repeat every few days until mealybugs are gone. See page 272 for more information about this pest.
FAMILY: PRIMULACEAE ORIGIN: SOUTHERN EUROPE AND TURKEY
THE CRISP, SHOOTING-STAR FLOWERS of cyclamens make lovely accents indoors in midwinter, their strongest season of bloom. From the centers of the plants, upright stems bear richly colored blooms with backswept petals in soft shades of pink and lilac, as well as bright red or snow white. New blooms replace the old for 2 months or more, all the while framed by lovely green heart-shaped leaves.
Cyclamen (Cyclamen persicum)
Many people discard cyclamens when they begin to deteriorate in spring, but they often can be brought back into bloom. Allow the foliage to dry until it withers in late spring, and then clip off the old foliage. Place the dormant plant in a cool, dark place for up to 3 months, providing just enough water to keep the roots from drying out completely. In late summer, return the container to a bright location, and repot the plant in fresh soil as soon as new growth appears. Resume watering and feeding, and blooms should emerge 2 to 3 months later.
Light: Bright, including 1 to 2 hours of direct sun in winter.
Temperature: Cool (60–70°F/16–21°C) year-round. Plants can tolerate cold to around 40°F/4°C.
Fertilizer: Feed every 2 weeks with a high-phosphorous plant food, mixed at half strength. (Do not feed dormant plants.)
Water: Keep lightly moist at all times. Provide water by placing pot in a shallow container of tepid water for 15 to 30 minutes. When watering from the top, avoid getting water in the plant’s crown.
Soil: Any good potting soil is fine. If you plan to keep a purchased plant for another year, promptly shift it to a slightly larger pot to provide room for growing roots.
Repotting: Repot soon after purchase and again following the plant’s rest period, just before new growth commences in late summer.
Longevity: 6 months to several years. Regardless of age, discard plants that show weak growth or are plagued by pest problems.
Propagation: By seeds. Seeds are small and slow, so it’s best to purchase new plants, which are usually seedlings less than a year old.
Selections: Varieties vary mostly in terms of size, which ranges from 6 in/15 cm tall for very dwarf selections to about 12 in/30 cm for larger varieties.
Display tips: Cyclamens are ideal plants for a sunny winter windowsill.
Leaves and flower stems collapse.
CAUSE: Dry soil.
REMEDY: Cyclamens are prone to sudden fainting spells when their roots dry out. Prompt watering will usually bring them back quickly. Stems or flowers that fail to respond to watering can be pinched off. If plants must be left unattended for a few days, move them out of the sun to help them retain water until you return.
Oldest leaves turn yellow and shrivel.
CAUSE: Accelerated aging caused by warm temperatures.
REMEDY: If possible, move plant to a place where it will remain cool at night. Pinch off old leaves as they fail and continue to feed and water plant regularly.
Mold appears near the soil’s surface, some stems become limp and wither.
CAUSE: Gray mold or other stem rot.
REMEDY: The cool, moist conditions cyclamens need put them at high risk for fungal diseases that affect the crown of the plant. Try to keep the crown dry by watering plant from the bottom, or by dripping water just inside the edges of the pot. Improve air circulation by pinching out old flower stems and leaves. Discard badly affected plants.
Leaves are limp and pale; webby material on leaf undersides.
CAUSE: Spider mites or cyclamen mites.
REMEDY: Isolate plant and consider discarding it, because the ability of cyclamens to recover from a mite infestation is quite weak. If you want to try to save an infested plant, snip off badly affected leaves and treat plant with a neem-based insecticide.
FAMILY: ASTERACEAE ORIGIN: CHINA
COLORFUL AND AFFORDABLE, potted chrysanthemums also help remove chemical pollutants from indoor air. Their natural bloom season is autumn, but greenhouse growers bring them into bloom year-round by controlling how many hours of light the plants receive. Careful feeding regimens and growth regulators are also used to produce stocky plants crowned with large, uniform blossoms. If purchased when the blooms are just beginning to open, chrysanthemums often stay in bloom for 6 weeks or more.
Chrysanthemum (Dendranthemum morifolium)
Enjoy your potted mum while the blossoms last, because the plant will never look so good again. You can transplant it to a garden and possibly get another season of bloom, but many florist mums are not hardy in cold climates. Most people dispose of the plants after the last flowers fade. While you share company with them, do not allow pets to chew the foliage, which can be poisonous.
Buds fail to open.
CAUSE: Plant was severely stressed in transit or deprived of sufficient light.
REMEDY: Place plant where it will receive a few hours of direct sunlight and hope for the best. Buy plants that show one or two blossoms beginning to open.
Foliage wilts.
CAUSE: Too little water.
REMEDY: Sometimes pots are so packed with roots that the water you give them runs over the roots and down the insides of the pot rather than soaking in. Rehydrate badly dried-out roots by placing the pot in a pan of water for 30 minutes while also watering it from the top.
Small, wedge-shaped, green insects on plant stems or leaf undersides.
CAUSE: Aphids.
REMEDY: Rinse plant thoroughly with a fine spray of water. Apply a soap spray to kill any survivors. Dispose of badly infested plants.
Lower leaves turn yellow or brown while plant is still blooming.
CAUSE: This is a natural growth pattern for mums.
REMEDY: If you don’t like looking at the failing foliage, cut the best bud-bearing stems, remove the lowest leaves, and display them in a vase. Cut chrysanthemum blossoms often last longer than flowers on living plants.
FAMILY: EUPHORBIACEAE ORIGIN: MADAGASCAR
BIBLICAL SCHOLARS CHALLENGE THE BELIEF that Euphorbia milii was the plant used to make Christ’s crucifixion crown, yet it is still an apt name for this semi-succulent plant. In Thailand, it is often said that the plantkeeper’s luck in life is foretold by the number of flowers his or her euphorbia produces. Today’s hybrid versions should make you lucky indeed, because breeding improvements in the last two decades have resulted in euphorbias with bigger, more numerous blooms than ever before. The blooms are actually bracts, which persist for several weeks, and the plant’s thorny, grooved stems add to its allure. Plant height, which can exceed 24 in/60 cm, is easily controlled with pruning of the growing tips.
Crown of thorns (Euphorbia milii)
Accepting of a wide range of temperatures, this euphorbia thrives in the dry air of modern homes and offices, and survives occasional neglect. When given abundant light and good care, it is capable of blooming almost year-round. Be careful, because this plant is poisonous if eaten, and the sap can cause skin irritation in sensitive individuals.
Leaves turn yellow and drop.
CAUSE: Too much water.
REMEDY: This plant stores water in its thick stems, so it needs less water than other houseplants. Water less heavily and less often, especially in winter. Plants sometimes shed leaves in winter in response to low light, and regrow new foliage in spring.
Plant does not bloom.
CAUSE: Too young; not enough light.
REMEDY: Very young plants often do not bloom until their second spring. Strong light also promotes blooming, so consider moving your plant outdoors in summer. Then allow it to rest in a cool, well-lit room in winter. Spring is usually the strongest season for abundant blooms.
Leaves are present only at stem tips.
CAUSE: Natural growth habit, which can be improved with pruning.
REMEDY: When plants become tall and leggy, prune them back by half their size in late spring, and set the pruned growing tips to root in a separate container. New branches should emerge from latent nodes below the pruning cut.
Small, wedge-shaped insects are present at new growing tips.
CAUSE: Aphids.
REMEDY: Various aphids that plague wild milkweeds can infest plants that are taken outdoors in summer. Clean plants with a fine spray of water, and treat with insecticidal soap if problem persists.
FAMILY: EUPHORBIACEAE ORIGIN: MEXICO
THE MOST POPULAR OF ALL BLOOMING HOUSEPLANTS, yearly poinsettia sales now top 75 million plants. Almost all are sold during the winter holiday season, and plants that receive good care may keep their looks well into winter’s second half. However, keeping the plants and regrowing them for a second season is quite difficult unless you live in a tropical climate where the plants can be kept outdoors. Indoors, the regrowing process involves pruning the plants hard in spring and then rooting the stem tips that emerge. Beginning in October, the plants must have 14 hours of continuous darkness nightly, for 8 to 10 weeks, before they will set buds.
Poinsettia (Euphorbia pulcherrima)
Poinsettias come in various sizes, from 6 in/15 cm miniatures to big, bushy plants that stand 18 in/45 cm tall. Red and white are the most popular colors, but many others are available, including decorator-friendly shades of peach and burgundy. When buying plants, look for nicely colored bracts and deep green leaves. As soon as you bring your plant home, alter the decorative wrapping as needed to promote good drainage (see “Fixing Floral Wrappings,”). Poinsettias grow best when they receive bright light, but they don’t mind being shifted about as needed to accommodate changing needs for space during the holiday season.
Light: Bright filtered light.
Temperature: Average room temperatures (60–70°F/16–21°C). Cool conditions prolong bloom time.
Fertilizer: Not absolutely necessary, but plants purchased early in the season benefit from feeding with a high-phosphorous plant food every 2 weeks.
Water: Keep soil lightly moist at all times. Large plants often need water every other day.
Soil: Should repotting be needed, any good potting soil will do.
Repotting: Not generally needed unless stem cuttings are rooted in early summer and grown in small, 4 in/10 cm pots.
Longevity: Less than 1 year.
Propagation: Root stem tip cuttings in July and grow them outdoors in filtered shade.
Selections: There are hundreds of cultivars, and the names change often as improved varieties replace old ones. Choose plants based on colors you like, and be picky about the condition of the plants.
Display tips: Should a plant lose its leaves and become lanky while still holding bracts, cut them off and use them as cut flowers.
Bracts begin to show color but remain small and pale.
CAUSE: Plant needs more light.
REMEDY: Buying a young poinsettia in which the bracts have yet to mature is a good idea, but these plants need plenty of light and occasional feeding to help them attain perfection. After the pea-sized yellow flowers swell and open, the poinsettia is fully mature and can be placed in less light and given routine care.
Leaves drop within days after plant is purchased.
CAUSE: Chilling injury.
REMEDY: Poinsettias that are exposed to temperatures below 50°F/10°C often develop this problem. Purchase plant from a store where the plants are displayed far from cold entryways, and place plant in a roomy paper bag when carrying it to your car, which should be warm and ready to transport the plant home.
Leaves and bracts droop despite attentive watering.
CAUSE: Plant was kept wrapped in a restrictive sleeve too long; root rot due to overwatering.
REMEDY: Plastic or paper sleeves protect poinsettias in shipping, but these should be removed as soon as they arrive at the store. Do not buy plants that have not been set free from their sleeves unless they arrived at the store earlier in the day. Sleeving a plant for a quick ride home will do it no harm. Be careful not to overwater poinsettias, which often happens if the drainage holes in the bottom of the pot are blocked by decorative wrapping.
Bract color fades.
CAUSE: Too much sun.
REMEDY: Direct sun can bleach the bracts of deeply colored varieties, and the condition is irreversible.
FAMILY: GENTIANACEAE ORIGIN: SOCOTRA ISLANDS, OFF THE COAST OF EAST AFRICA
A BEAUTIFUL BLOOMER that will bring color and fragrance to any room, exacum is often called Persian violet, but it is more closely related to garden impatiens than to true violets. Exacum can be grown outdoors in shady gardens, but it is most popular as an indoor blooming plant. The shiny green leaves studded with .5 in/1.25 cm-wide, bell-shaped, violet-blue flowers give this plant a refined look, and its neat, 12 in/30 cm-high, mounding form makes it a perfect fit for sunny windowsills.
Persian violet (Exacum affine)
As for disadvantages, exacum is a short-lived annual best regarded as a temporary color plant. If blossoms are pinched off as soon as they fade, and the plants get good light, water, and fertilizer, they may bloom for several months. More often, this plant blooms very heavily and then promptly begins to fail. For the longest possible show, choose a plant with buds that are just beginning to open, and deftly shift it to a slightly larger container. This eases watering challenges, as exacum often dries out quickly when kept in the bright light it finds most pleasing.
Light: Bright light from a south, east, or west window.
Temperature: Average room temperatures (65–75°F/18–24°C).
Fertilizer: Feed every 2 weeks with a complete houseplant fertilizer that includes micronutrients.
Water: Keep soil constantly moist; mist plant regularly to boost humidity.
Soil: Potting soil amended with peat to increase acidity.
Repotting: Beneficial if plant is so rootbound that it is difficult to water. Do not disturb the roots during repotting.
Longevity: A few weeks to several months.
Propagation: Plants are usually grown from tiny seeds, which germinate in 2 to 3 weeks. Propagating plants from stem cuttings is possible, but not easy.
Selections: Most exacums feature violet-blue flowers, but varieties are occasionally offered in white or deep violet-purple. Indoors, lighter shades tend to show better than darker ones.
Display tips: Use exacum as a feature plant in your favorite room when the plant is in full bloom. Blossoms have a fleeting fragrance that is sweet yet light. When purchased in the summer, exacum can be kept outdoors on a shady patio and brought indoors when it attains full bloom.
