Companion planting is a system that lends itself to trial and error. Over the centuries, gardeners have planted certain plants in close proximity and they have noticed the end results. Plants naturally take in air and minerals and release chemicals through their own secretions or root excretions. For example, a plant that excretes nitrogen into the ground can make this element available to others that need a nitrogen-rich soil.
Some plants are found to lift many trace minerals from the soil in which they grow. Plants like these can be especially useful when turned into compost or mulch because they will then feed other plants with these valuable minerals. Allow the plants to grow to a mature size, then turn them under for green mulch or harvest them and bury them in the compost pile.
History
Historically, there is no one point where we can say that companion planting actually started or at what geographical location in the world it originated. Many agricultural practices have been used for centuries with the origins lost – companion planting is just one of them.
In North America, the search for the origin of companion planting leads us back to American Indians and their companion planting practice called “Three Sisters.” The Iroquois of the Northeastern United States and Canada primarily used this practice and it involved planting corn, beans, and squash. These crops were the mainstay of the Iroquois’ diet and were believed to be special gifts from the Great Spirit; as such, they were under the protection by the spirits called the Three Sisters. They were planted as a mainstay crop for the people and their system of planting was revered.
The Iroquois planted the three crops together. Corn gave structure and support for the bean plants to climb up; the beans replenished the soil with nutrients for both the corn and squash; and the large multiple leaves of the squash vines offered a protective mulch that helped the plants conserve water while providing weed control for all three plants. When planted in this special way, the plants thrive in a small space and are capable of producing high-quality yields with minimal to no environmental impact.
Over time, many other companion planting combinations were tried, with varied results. Much of this knowledge was handed down from generation to generation, and some of it today may be found to be folklore of other cultures.
Plants and their identifications have changed over time, as have horticultural methods, climates, and soil content. There has also been the introduction of chemically based pesticides and fertilizers and advancement in seeds, propagation, and cultivation. All of these affected the basics of gardening but the premise of companion planting remains the same.
Biological Benefits of Combining Plants
There are specific biological effects of combining plants, such as:
• Nitrogen Fixation – plants that increase nitrogen in the soil
• Pest control – plants that repel “bad” pests or attract in “good” insects to the garden
• Enhancing flavors – the plants that can subtly enhance the flavors of other plants
• Level interaction – plants that grow on different levels to provide ground cover or work as a climbing trellis
• Pest trapping – plants that can attract certain pests in order to keep them away from other plants
• Shelter plants – plants that provide windbreaks, shade, and prevent soil erosion
• Crop rotation – plants can be grown and tilled into the ground to provide nutrients for the next crops or rotated from bed to bed to minimize problems
Nitrogen fixation
“Nitrogen fixation” may sound odd, but it is the term for plants such as peas, beans, and clover that can “fix” or excrete atmospheric nitrogen for their own use and for any close neighboring plants thanks to their relationship with the bacteria in the ground. This relationship increases the nutrients in the soil, making it available to other plants that are growing beside it – a perfect relationship for companion planting – one plant “helping” another. The nutrients are also available to plants grown in the soil after the legumes are pulled.
Plants that have the bacteria that can convert the nitrogen in the air into nitrogen compounds and bind them to the soil include alfalfa, red clover, and bluebonnets. These last plants are intended to be turned under at the end of the season as a green manure, or organic compost for the benefit of the garden.
Forage legumes are commonly planted with grasses to minimize the use of nitrogen fertilizer. Another example takes us back to the American Indians and their system of planting beans with corn. The beans helped the corn receive enough nutrients by “fixing” the nitrogen that allows it to grow and produce excellent yields.
Pest control
Companion planting is often considered part of the organic gardening philosophy as it avoids using chemicals and pesticides. Controlling pests through natural means can have many positive effects on the garden such as:
• Preventing the spread of disease through your garden
• Decreasing the damage pests cause
• Reducing the effect of chemicals you may have been using in the past
Keeping away pests can help your plants grow and flourish in ways you never thought possible. For example, planting catnip in the garden deters aphids, ants, Japanese beetles, and weevils. Mice also do not like the plant and will not stay in a garden where catnip is planted. As the plant is bushy with a light green leaf and dark purple flowers, it is an attractive yet functional addition to any garden.
This type of planting can take some time for the results to show. If you have planted marigolds to deter nematodes, the effect is not going to show itself instantly or even in the next month. Instead, it may take a full year’s cycle before the marigolds have done their job. Gardeners who claim the system has failed often have not given the plants time to work. The plants need time to take hold and the life cycle of the pests need time to die out.
Companion planting can also attract the “pests” you do want. Why would you want any pests? Some insects are helpful in the garden. Wasps, for example, are an asset for most gardens because they eat grubs. Some insects are also pollinators. Some plants require pollination because they cannot reproduce on their own or bear fruit unless the pollen is delivered from one plant to the next. The fastest and most efficient way to do this is to have the right insects in the garden. A few beneficial pests are bees, wasps, birds, and dragonflies.
Enhancing flavor
Companion planting is not an exact science; it is a natural science. However, some combinations have proven themselves over and over again. A prime example is basil, which goes great with tomatoes in the kitchen and can also enhance the flavor of the tomato if it is grown beside it in the garden.
Most herbs have been found to enhance the flavor or fruits and vegetables that are grown in close proximity, and basil grown beside tomatoes is a prime example. Bee balm is also known to improve the growth and flavor of tomatoes. German chamomile, also called wild chamomile, has a strong aromatic odor and is believed to improve the growth and flavor of cabbages, cucumbers, and onions when grown beside them. Whether that is due to the increase in nutrients or because the plants share the common soil where nutrients and by-products are expelled and mixed, gardeners swear by the practice.
Level interactions
Level interactions, also known as physical space interactions, involves planting tall plants with short plants to provide shade and even structure. Tall, sun-loving plants will shelter short, shade-tolerant plants, which results in better production and can even offer pest control. A good example of this type of relationship involves the popular corn planted with squash in the Three Sisters example. The tall corn throws shade for the lower squash but also the corn appears to stop an insect called the squash vine borer beetle. Another added benefit is the prickly vines of the squash deter the raccoons from stripping the corncobs.
When planting this way, you can plant two or even three different levels of plants, including a ground cover crop at the base. If the soil has sufficient nutrients, then the plants can thrive.
Pest trapping
Another term for this type of companion planting is trap cropping. With this system, a specific plant will be placed in the garden for its ability to attract a pest, thus keeping the pest away from the rest of the crops. The trapped insects on the plants can be disposed of in another way, such as bending the branch or stalk of the plant in a bucket of soapy water to kill the insects. Or, if you prefer, you can leave the plant, now full of bugs, alone for the season because the bugs will remain there.
A prime example of a pest is the diamondback moth, which can destroy a cabbage crop. Plant collard greens close by to attract the moth, keeping it away from the cabbage. Rose plants are another example — to keep the Japanese beetle out of your roses, plant old-fashioned four o’clocks, a beautiful perennial aptly named because the flowers only open after the sun has gone down.
The mustard plant is a big contender in this category as well because it will attract cabbage worms and harlequin bugs. Cabbage worms refer to several species of caterpillars but the main one in North America is small, fuzzy, bright green, and feeds on cabbages, broccoli, and cauliflower. The harlequin bug, indigenous to the southern United States, looks like an orange and black stink bug and can destroy an entire crop of cabbage, Brussels sprouts, turnips, kohlrabi, or radish. In fact, if they cannot find any of these, they will move on to potatoes, okra, beans, beets, and even fruit trees and field crops. However, if you plant the mustard plant in a separate area of the garden early in the spring, the bugs will gather on it. You cannot get rid of them by pulling up the plants because the bugs will scatter and will simply find another plant to latch onto. Instead, you can dunk the leaves or bend the stems into a bucket of soapy water to drown the insects, or spray it with insecticidal soap. Even better, consider planting the mustard plants with some of the plants that attract parasitic wasps or tachinidae flies, such as tansy, clover, and dill, as they are both predators of the harlequin bug.
Shelter planting
One of the most helpful benefits of combining plants is the ability to provide natural windbreaks, shade, and trellises. Some plants can grow to different heights while occupying the same space. The example of planting corn and beans together applies here again; the cornstalk serves as a trellis for the beans to climb, while the beans do not harm the corn stalk or the corn and they help by adding nutrients to the soil.
Heavy winds can damage gardens by removing mulch, topsoil, and eroding packed beds and hillsides. Rain and hail can also cause severe damage by beating down young seedlings and tightly packing a new soil covering that has just been laid. This is where a tight ground cover can help. By carefully selecting the right type of ground cover, the gardener can help prevent soil erosion without harming nearby plants. The best groundcover plants are usually those that prefer shade. For example, cut-and-come-again salads, meaning salad greens that do not need to reach maturity before harvesting and can be cut to grow again, are easy to grow, and all they need is a narrow band beneath other rows of plants. They create a beautiful groundcover while taking advantage of a space that is not very useable for other plants. Clover is another example of a ground cover that likes shade and will help keep the soil covered against wind, rain, and hail.
Crop rotation
History has shown the problems of not utilizing crop rotation – think of the Irish Potato Famine problem of the mid-1800s. In this case, blight, a fungus, destroyed three-fourths of all the potato crops for years, creating widespread famine and eventual death for much of the population. Potato was the main crop of the country and the most widely consumed food of the middle- to lower-class people. The people starved when the potato crop failed because they had no secondary crops to succeed as food or cash crops. When only one crop is planted, this is called monoculture. Planting potatoes, sunflower, or safflower in the same place year after year can lead to an extensive spread of Verticillium fungus and kill off the entire crop for the season and even affect future crops.
Crop rotation means relocating the crops to a different part of the garden every year. When companion planting, you need to ensure succeeding crops are always a completely different genus or species than the previous year’s crop to minimize disease. The rotation sequence is usually at least two years, but it may be longer. For example, if you plant potatoes in one spot, do not plant them in that spot again for at least three or even four years. The reason you want to rotate your crops is to accomplish the following:
• Minimize disease
• Discourage insect infestations
• Deter weeds
• Improve soil fertility
• Reduce erosion
• Reduce the use of chemicals
Number of beds to rotate
The number of crops you want to grow will determine the number of beds that you rotate. If this is your first attempt at establishing a vegetable garden, it is best to start small. A 10 foot by 15 foot plot will be large enough for someone just starting out. It does not have to be a square so consider a round, rectangular, or even an oval-shaped garden.
You will need to decide whether you will be companion gardening at ground level or in raised beds. Raised beds allow for more intensive planting and can provide just as many vegetables as their larger counterparts. When considering crop rotation with raised beds, you will take the crop from Bed 1 of this year and move it to Bed 2 next year, then to Bed 3 in the year after, and so on. If you are not sure how many beds to create, try for four. You can plant in three beds while allowing the fourth to rest as you build it up with compost and green manure.
Most people group beds by classification; others group them with “like” qualities. For example, you could divide crops by the nutritional requirements:
• Group 1: Leafy plants that thrive on oxygen — lettuces and salad greens, broccoli, cabbage, cauliflower, and kale
• Group 2: Fruits that need phosphorus — squash, melon, pumpkin, tomatoes, peppers, and cucumbers
• Group 3: Roots that love potassium — onions, shallots, garlic, leeks, carrots, turnips, and radishes
• Group 4: Soil replenishers — legumes, corn, potatoes, beans, and peas
Another way to divide crops is by these classifications:
• Cultivated row crops — corn and potatoes
• Close-growing grains — wheat and oats
• Cover crops — clover and grasses
There have been many studies showing that certain crops should (or should not) follow others for the best yield. Beets will yield best when they follow barley or wheat; soybeans should follow beets; and potatoes should never follow tomatoes.
For more information on crop rotation, here are some online resources you can reference:
• Manitoba Agriculture, Food, and Rural Initiatives’ Web site offers extensive information on crop rotation research and the inherent benefits of this type of program — www.gov.mb.ca/agriculture/crops/forages/bjb00s43.html.
• Ontario Ministry of Agriculture Food & Rural Affairs’ Web site offers information on crop rotation for agricultural purposes — www.omafra.gov.on.ca/english/crops/field/news/croptalk/2002/ct_1102a6.htm.
• North Dakota State University’s Web site offers information and charts on the crop rotation for various agriculture crops and the benefits each type of crop provides — www.ag.ndsu.edu/pubs/plantsci/crops/eb48-1.htm.
To decide how to rotate your own crops:
• Make a list of the crops you want to grow
• Fertilize and mulch the current bed for the crop it contains
• If you are growing legumes, always plant them after grains to replenish the nitrogen in the soil taken by the grain crops
• Incorporate as much compost or green manure into your garden as possible at all times
• Keep careful notes of your crop rotations so you know from year to year what was planted in what location
Another consideration after crop rotation is how to maximize your yield. Because each plant requires different nutrients and is also used as a food source for different destructive pests, planting a different crop in the space each season can both reduce the presence of pests and replenish the soil, giving the gardener the best chance of increasing yield.
Beans and corn once again offer an easy example. Corn requires a great deal of nitrogen in order to produce a good yield, and beans fix additional nitrogen into the soil. So by following beans with corn, you will have a greater production of corn.
Cover crops
Cover crops are a second crop planted to improve the production of the primary plant. This is an important concept of companion planting where one plant can help others. Examples of this type of crop include grasses that are grown in orchards or legumes grown during the winter season to improve the crops. Some plants like rye and clover can be planted immediately after a crop is harvested to protect and nourish the soil. In some instances, the secondary plant is grown immediately to absorb any nitrogen left in the soil after the fall harvest that would otherwise escape into the groundwater.
The home gardener needs to understand that some plants help build soil, and others leach the nutrients out of it. Most cover crops help build the soil and can:
• Provide protection from sun and weeds
• Give food for beneficial insects
• Provide nutrients for other plants by being worked into the soil at the end of the season
Cover crops are usually divided into legumes and non-legumes. Legumes, which include beans, peas, and lentils, are able to fix nitrogen, and can provide at least some of the nitrogen requirement for the next crop in rotation. Legumes generally provide more nitrogen, but less total organic matter than non-legumes. The advantage lies in their nutritional value, so they are often used anyway. Non-legumes include wheat, rye, corn, buckwheat, oats, and barley. They are vigorous growers and will provide organic matter to be worked back into the soil.
Within both legume and non-legume groups, there are species specific to either a warm season or a cool season. By using both types of plants, it is possible to improve the overall productivity of the soil. During the growing season, cover crops prevent soil erosion and help control weeds. At the end of the growing season, the cover crop is dug under, without pulling the plants, to improve soil structure, aeration, water holding capacity, and nutrient content. Even with cover crops, it is important to have a plan for rotating different grains. Using the same cover crop year after year will increase plant-specific pathogenic organisms. By switching out to a different cover crop, the gardener will interrupt the life cycle of the organism and discourage it from multiplying.
If you are not using raised beds, you can actually mow cover crops to provide instant organic mulches for the growing plants. Think of a large orchard planted with special grasses; mowing them back helps keep the growth in check and produces good mulch for the orchard.
Planting cover crops is easy if you are using seeds, which is one of the easiest and cheapest ways to plant large areas; you can sow the seeds like you are spreading chicken feed to your fowl. Walk forward through the garden and toss out handfuls of the seed in a circular motion, attempting to cover the area evenly. If you are sowing several different kinds of seeds, you can either mix them into one general seed pile first and then throw them all out together, or you can sow first one and then the other. If you are sowing raised bed gardens, you cannot walk forward so it is best to walk along the side and try to spread the seed evenly throughout the bed.
Now that you have an understanding of how to start companion planting, you will want to decide on what kind of plants to include in your companion garden.
Ways to Choose your Companion Plants
Every gardener has different tastes and different needs and every garden will present growing conditions that offer up a challenge. The growing conditions between your yard and your neighbor’s yard can be different, and there can even be differences between your front yard and your backyard. And, as any gardener will tell you, the geographical area of the country in which you live will often dictate the way that your companion plants work together. A distance of only a few hundred miles can present an entirely new set of landscape, temperature, and humidity conditions. Soil may be rockier or sandier or the pH may be higher or lower, affecting conditions enough to change the transplanted gardener’s approach to his or her garden.
Every garden contains sun, shade, sheltered spaces, open areas, dry spaces, and places that retain water. These mini-ecosystems must be understood and taken into consideration before designing a garden or choosing the plants to go in it. If space is unlimited for the garden, then crops, herbs, flowers, and shrubs may all be placed where it best suits them. Few gardeners have that freedom in most cases, so space is at a premium.
As with any garden, you need to understand what you have to work with before you create your companion garden. The type of soil, the amount of water available or that you will need, and the amount of sun or shade available should also be considered. Then you have to consider the types of plants that will fit into and flourish in your garden. If you are looking to incorporate a more intensive companion gardening system into your plans, the soil will need to be rich and heavy in nourishment to accommodate the extra plants.
You must select the right plants to accommodate the planting area, rather than the other way around. Let us take a closer look at some of the ways you can select plants for your garden.
Choosing by climate and geographical location
When you purchase plants in a garden shop, they will be tagged with a hardiness zone number.
The hardiness zone is a system the U.S. Department of Agriculture (USDA) developed as a rough guide to the plant’s hardiness. The term “rough” applies because hardiness depends on many factors, such as:
• Duration of cold or hot weather in any given year
• Force of wind
• Depth of roots
• How much water is in the soil at the time frost first hits
The USDA has divided the United States and southern Canada into 11 planting zones or USDA Plant Hardiness Zones. The USDA has defined these regions by a 10 degrees F difference in the average annual minimum temperature in the area. The higher the USDA hardiness number, the warmer the temperatures are for gardening in those planting zones. This means that areas within northern Minnesota are in USDA planting zones of 2 and 3, and southern Florida is in the USDA zones 9 through to 11. However, most of the United States falls into the USDA zones of 4 through 8, which cover areas where the average lowest temperatures range from -20 degrees F to 20 degrees F.
Plants and seeds will normally be labeled according to these USDA planting zones, meaning the zone on the label is the zone in which a gardener will be the most successful in the growing that particular plant. The zones can be closely linked, so it is possible that although you live in zone 7, your weather this year (or this season) will act like zone 8. This means that severe winter weather may kill off some plants or an especially hot summer may do the same.
There is an interactive USDA hardiness zone map available through the U.S. National Arboretum Web site at www.usna.usda.gov/Hardzone/ushzmap.html. Find your location on the map and understand the zone you are in and what this means for your garden. No matter how much you love a wisteria plant, if you are located in the far north it will not survive. Likewise, if you love ferns but live in Arizona, you probably will not have a lot of success — besides, wilting plants are not attractive in any garden.
Microclimates
A microclimate is defined as a mini-climate or a small, specific place found within a larger or macroclimate. This happens as a result of a different type of exposure to the elements. For instance, sunny hidden places in the garden that are sheltered from harsh winds and frosts can contain microclimates.
Consider a south-facing home surrounded by half an acre of land. The front yard receives hours of hot sun and the brick house and the brick wall separating the front from the back will reflect heat, so plants that are closer to these areas may bloom earlier and later into the seasons. They are also more likely to overheat in the summer. Moving to the back or the property, the small deck has a shady part closest to the house, while the outer edge gets more reflected light. The border of the brick wall receives no light at all and is perfect for a shade garden.
Such unique microclimates can be great for experimenting with plants that might otherwise be considered not hardy enough for you geographical location. If you have a plant reported to be for zone 4 and you live in zone 3, you can try growing the plant in a warm sheltered microclimate.
Vegetables are also classified according to frost survival, and these too may be manipulated somewhat if your garden has microclimates. In addition, they can be covered using old cotton sheets or heavy plastic if there is danger of imminent frost. This is a common practice with strawberries if night temperatures drop unseasonably low.
Choosing by light/shade
Another major consideration is the amount of sun the garden and plants will receive in a day. Most gardens will require at least six to eight hours of sunlight a day, even during the spring and fall. Many times when the gardener is unsuccessful with a plant, it is simply because it is not receiving the full amount of sun, even though the gardener feels that the plant was placed in a sunny area.
The number of hours of sun available for your plants is not the only factor to consider; you also have to consider the intensity of the sun. Gardens that are exposed to the east receive cool morning sun and are shaded in the afternoons. Gardens with a western exposure are shaded in the morning and receive very hot sun in the afternoon. If delicate plants are placed there, even if they are considered sun loving, you may notice bleaching and sunburn — browning, dying leaves — especially in warmer climates. The flowers will also fade quickly in the intense heat.
Here is a list of light conditions you might see on the plants at your local nursery:
• Full-sun plants: These must go in areas that get a minimum of six hours of direct sunlight every day.
• Partial sun, also called semi-shade: These plants thrive underneath a trellis, a tree branch, or a place where the sunlight is filtered. They need some direct sunlight, but it can alternate with periods of shade.
• Full shade: These plants require light, but not direct sun. They should be planted under dense trees or in the shadows like on the north side of a house or wall area.
Choosing by nutrient needs
All plants have specific requirements to make them grow and produce in the way they are meant to, but these requirements differ from plant to plant. Some vegetables deplete the soil of particular nutrients. For example, sweet corn is a heavy feeder that takes a lot of nitrogen (and plenty of other nutrients) from the soil. If you plant climbing beans at the base of each growing corn stalk, then the bean’s roots can fix the nitrogen from the air into the soil where the corn can make the best use of it. Other legumes, like peas, grow well with other nitrogen-hungry vegetables like cabbages, broccoli, and cauliflower.
Another way of choosing companion plants is by how they grow and where they receive their nutrients. Two different types of vegetables can feed at two different soil levels, which is what happens when you grow carrots and onions together. Onion roots stay just under the surface of the ground whereas carrots push their roots very deep, which is where they feed. By growing the two together, you boost the productivity of your beds.
Choosing by water needs and availability
Water requirements vary from plant to plant and water availability varies from garden to garden. Some dirt is porous and the water will seep away quickly while other garden beds are made with mulch and rich compost that will hold water for longer. If your garden is on a hillside, you need to watch that all the plants’ water does not drain down the hillside and away from the plants’ roots.
Another consideration is the type of watering system you have available. Are you close to a lake and is there ground water close to the surface? Or do you live in the desert and you need to water a minimum of twice a day? Are you prepared to face an increase in your water bill, or are you looking to have plants that do not need heavy watering? Do you already have enough hoses to cover the size of the garden you are planning? Have you considered using soaker hoses? They work well in many gardens as they can deliver a slow and steady water supply.
Choosing by soil conditions
The soil that is present in the garden must be rich with nutrients to help the plants grow to their full potential. Soils may consist of clay, loam, sand, shale, or rock. You can test what kind of soil is in your garden by taking a shovel, digging a hole in the ground, and pouring a bucket of water into the hole. A very hard soil, like one with a clay base, will never drain; the water may stay there for days. Clay soil will drain, but it may take three hours or even more. A clay/loam mixture will drain somewhere between 30 minutes and two hours. A loam or a sandy loam will drain between ten minutes and an hour. Pure sand will drain so quickly you are unable to keep the hole filled. And of course, if you find rock just below the surface, you will not be able to dig a hole at all. You will need to keep the soil condition in mind when you choose your plants or you will need to improve the soil first.
Soil pH
The acidity of the garden soil is also important and is referred to as its pH level. It is measured on a scale of 1 to 14 with 7 being neutral. A value above 7 means the soil is alkaline, or basic, and if the soil is below 7, it indicates an acidic soil. The acidity reflects the amount of calcium, in the form of chalk or lime, in the soil. This level can change over time and can be affected by rain and the crops growing nearby. Clay soils tend to be alkaline and sandy soils tend toward acidic levels. There are three common terms used to describe the soil pH. Sweet soil has mid-range pH (between 6 and 8) and is ideal for most plants. Sour soil is acidic with a low (below 7) pH, and bitter is used to describe alkaline soil, meaning it has a pH higher than 7.
The pH level is so important because it can affect the release of nutrients and have an impact on worm and micro-organism activity. The pH of a garden soil will affect plant growth. Most vegetables do well in a slightly acidic soil (around 6.5 to 7) as they can more readily access the nutrients in this type of soil. Some plants do not have a preference and some are highly susceptible to pH conditions. You can check with your local nursery to discover what the soil needs are for any plants you wish to plant in your garden. If you are going to test the pH levels in your garden, it is recommended that you take soil samples from two to three different locations in the garden.
None of these garden conditions need to be permanent; it is possible to offset nearly all of the circumstances listed above. If a drought situation exists, irrigation can be put into place. Windbreaks can be built to keep off the worst of the wind. But it is always the easiest to work with the natural conditions that exist in your area. The goal of the garden, after all, is to be beautiful and productive, whether what is being produced is food or flowers.
Regardless of the soil’s existing condition, adding good topsoil will help your garden grow. Adding compost will enrich the soil with nutrients, as will adding well-rotted manure. Some gardeners use fertilizer throughout the blooming season to increase the amount of flowers and increase the yield of the plants. If you prepare the soil well with topsoil, compost, peat moss, and manure, the garden will need minimal to no fertilizing throughout the season.
Where to purchase the ideal soil for your garden
Most major garden centers offer topsoil, either bagged or in bulk, fertilizer, compost, and manure from various sources. If you are uncertain about what you need, speak with a specialist to get advice on the right products. Many of these centers will also offer bulk sales where you can purchase large quantities of dirt. It is better to go to a garden center or a landscaping supply store for this type of material because if you purchase these materials online, you will usually have to order in large quantities, which will make shipping expensive. Your local center will also be able to advise you about problems with the soil in your area.
The compost and fertilizer will add nutrients and improve the texture and workability of the soil; the manure will add nitrogen; and the peat moss will increase the water-retaining capacity.
Choosing by color or appearance
Some gardens appear to have been designed by an artist with the beautiful use of colors, textures, and shapes and appear to meld into a beautiful harmony. Many times, this sort of garden has been carefully laid out with a particular color sequence in mind. Spring might be for the cooler colors — white, yellow, and purple — and in summer the hotter colors come into play — red roses, yellow dahlias, marigolds, and bright asters. Many gardeners love to mix violas and blue delphiniums with the yellow and reds. Other gardens may contain loads of white flowers, sweet alyssum, and climbing roses, mixed with the soft grays of artemisia, lavender, and lamb’s ear. The Hosta “Royal Standard” works well in these arrangements too.
If the garden area is very small, using a two- or three-color spectrum can be dramatic. When considering planting for color, consider what appeals to your eye. It may be the cooling whiteness, gray-green foliage, or the extreme hot of ruby red flowers. It may also be the combination of colors that appeals to you, such as lemony-yellow with blue and purple contrast.
Even a garden of all green can be beautiful. In this case, texture and pattern take the place of color. Green is restful, especially in the heat of summer. Consider planting glossy and waxy leaves, hairy or woolly leaves, or toothed and smooth leaves. Together these add interest to the green garden.
Many gardeners like to work with a color wheel to decide the best relationship between their garden’s colors. The color wheel is made of six segments containing the three primary colors (red, blue, and yellow) alternated with the secondary colors (green, purple, and orange). Green is between yellow and blue because it is a mixture of these two colors, purple is between red and blue, and so on. The color wheel is helpful because by looking at it, you can determine what effect a certain combination of colors might have. Colors that are close on the wheel, like orange and yellow, are more harmonious; colors that are opposites, such as purple and yellow, will present more of a contrast. This can help you determine whether you would like an exciting, dazzling garden, or one that is more gentle and relaxing.
The strength of the colors used will have an effect on the overall grouping. For example, a soft yellow, such as moonlight coreopsis, will have a soothing effect; a stronger yellow will be much more dramatic. If the garden has been planted and you find the colors are too strong, it is easy to lighten the contrast by adding a lighter shade of the same flowers that already exist. Make sure the softer tones of flowers or their foliage have a definite shape, and that enough of them are used to create the contrast. Otherwise, the lighter-colored plant will be overwhelmed and lost within the stronger colors. If your goal is to develop a scheme that offers richness, consider a garden of golds, reds, and shades of blue/purple. Foliage in this garden should vary from dark green to a purple shade.
White is often omitted from the garden because it tends to look chalky. White draws attention, especially in summer plantings, so it is usually not scattered throughout the garden. However, if used in small doses and mixed among red, yellow, and oranges, whites can accentuate the heat of these colors. If white has been rejected in the past because of its starkness, try a creamier shade instead (like the edges of hosta variety called “Francee”). Pastels and whites are especially enjoyable during twilight hours, particularly if backlit by the sun. Many gardeners select white jasmine, moonflower, and the climbing rose variety rosa x fortuniana just for these purposes.
If planting a first-time garden in a single color, consider using all green. Green is a very restful color and offers many shade varieties, including deep purple-green, true green, blue-green, gray-green, and yellow-green. Blue-green leaves will have a deepening effect, just as blue flowers will. Rustling pale or variegated ornamental grasses planted against deep green hollies or other glossy, strongly shaped leaves offer textural appeal.
A popular garden theme is to use a single color like an all-purple garden. To avoid the color coming across as monotone, use the many different shades like mauves, periwinkle, lavender, violet, and purplish-black. Some good plant choices for the purple garden include:
• Purple smoke bush
• Bronze fennel
• Purple basil
• Eggplant
• Burgundy bush beans
• Ruby perfection cabbage
• California lilac
• Cornflower
• Catmint
• Turquoise blue fruit
If you are gardening for color, consider these tips to have a long season filled with beautiful blooms:
• Determine your color scheme and then stick to it so the garden will not look chaotic.
• For extra interest, include a wide variety of plants: annuals, perennials, flowering shrubs, trees, roses, and bulbs. In the food garden, tuck some of these into the bare spots.
• Consider the seasons. The biggest challenge you will have when developing a new garden is to provide color from early spring through late fall. Do not forget to look for shrubs with bright fruit or trees with a great winter shape or fall foliage color.
• Use one or two bold plants to give focal points to your garden area. Foliage with a strong shape or texture can make everything else stand out. Consider adding cardoon to your garden.
• Plan to work through all the seasons because a garden evolves over time.
• Be willing to take out the plants that are not working and replace them with something else.
Choosing by genetically similar crops
Attempting to garden with natural conditions means much more than gardening by zone, climate, and soil type; it also means selecting plants according to their similarities or differences. When you select plants that are from the same botanical family, you are choosing those that are genetically similar. Grouping the plants together is an easy way to garden because in general their light, moisture, and soil requirements will match. They also often have the same pest problems and similar diseases, so it is possible to end up with trouble if you are not careful. Just be sure to read up on the problems that might exist with different plants.
Choosing by the critters that plants attract or repel
Certain plants fall into the “pest control group” of plants and the goal of planting them may be to attract beneficial pests or it may be to repel those that are harmful. Many gardeners also purchase beneficial insects, such as ladybugs and praying mantis, and grow the plants required for the insects to flourish. It is also possible to grow specific plants that will attract these “good” insects to your garden.
Here is a list of some easily attainable plants that attract a wide range of beneficial insects:
• Golden aster
• Goldenrod
• Marguerite
• Bachelor’s buttons
• Black-eyed Susan
• African daisies
• Calendula
• Dwarf morning glory
• Cosmos
• Sunflower
• Zinnia
• Buttercups
• Dandelions
• Lamb’s quarters
• Wild mustard
• Queen Anne’s lace
Just as some plants attract certain insects, others deter them. By combining specific deterrents with the vegetables, herbs, or flowers that bugs normally damage, you can successfully harvest plants without adding harmful chemical pesticides. Note that some of the deterrents are trap crops, which means they act as a decoy, drawing the pest away from the plants they are most fond of. For example, nasturtiums will trap aphids and mustard plants attract harlequin bugs.
Now that you know a little bit more about companion planting in general, the next chapter introduces wildflowers and weeds used in companion planting.