appendix A planting and maintenance

This section covers the basics of planning a vegetable garden, preparing the soil, starting seeds, transplanting, fertilizing, mulching, composting, installing irrigation, watering, weeding, crop rotation, and using floating row covers.

Planning Your Vegetable Garden

You can interplant Asian vegetables and herbs among your ornamental flowers-many, such as amaranth and peppers, are quite beautiful—raise them in large containers or planter boxes; or add them to your existing vegetable garden. If you have no vegetable garden, you can design one. The first step in planning any vegetable garden is choosing a suitable site. Most chefs recommend locating the edible garden as close to the kitchen as possible, and I heartily agree. Beyond that, most vegetables need at least six hours of sun (eight is better)—except in warm, humid areas, where afternoon or some filtered shade is best. Most annual vegetables also need fairly rich, well-drained soil with lots of added organic matter.

Take note of what type of soil you have and how well it drains. Annual vegetables need to grow fast and with little stress to be tender and mild. Their roots need air, and if the soil stays waterlogged for long, roots suffocate or are prone to root rot. If you are unsure how well a particular area in your garden drains, dig a hole about 10 inches deep and 10 inches across, where you plan to put your garden, and fill it with water. The next day, fill it again—if it still has water in it 8 to 10 hours later, you need to find another place in the garden that will drain much faster, amend your soil with much organic matter and mound it up at least 6 to 8 inches above the ground level, or grow your vegetables in containers. A sandy soil that drains too fast also calls for the addition of copious amounts of organic matter.

Find out, too, what your soil pH is. Nurseries have kits to test your soil’s pH and a university extension service can lead you to sources of soil tests and soil experts. Most vegetables grow best in soil with a pH between 6.0 to 7.0—in other words, slightly acidic. As a rule, rainy climates have acidic soil that needs the pH raised, usually by adding lime, and arid climates have fairly neutral or alkaline soil that needs extra organic matter to lower the pH.

Once you’ve decided on where you are going to plant, it’s time to choose your vegetables. Your major consideration is, of course, what flavors you enjoy using in the kitchen. With this in mind, look for species and varieties that grow well in your climate. As a rule, gardeners in northern climates and high elevations look for vegetables that tolerate cool or short summer conditions. Gardeners in hot, humid areas require plants that tolerate diseases well and must carefully choose heat-tolerant vegetables.

The USDA Plant Hardiness Zone Map has grouped eleven zones according to winter lows, a help in choosing perennial plants but of limited use for annual vegetables. Of more interest to the vegetable gardener is the AHS Plant Heat-Zone Map, published by the American Horticultural Society. The heat map details twelve zones that indicate the average number of days each year when a given area experiences temperatures of 86°F or higher—the temperature at which many plants, including peas and most salad greens, begin to suffer physiological damage. In “The Encyclopedia of Asian Vegetables,” I indicate which varieties have a low tolerance to high temperatures and those that grow well in hot weather. See the Bibliography for information on obtaining the heat map.

Crop placement must also be considered. Take care not to plant tall crops, such as cucumbers, on a trellis where they will shade sun-loving plants, such as peppers. Setting out a plan for crop rotation is wise at this point, too. (See the Crop Rotation entry on page 94.)

Other design features to consider include bed size, paths, and fences. A garden of a few hundred square feet, or more, needs a path or two and the soil to be arranged in beds. Paths through any garden should be at least 3 feet across to provide ample room for walking and using a wheelbarrow, and beds should generally be limited to 5 feet across, as that is the average distance a person can reach into the bed to harvest or pull weeds from both sides. Protection, too, is often needed, so consider putting a fence or wall around the garden to give it a stronger design and to keep out rabbits, woodchucks, and the resident dog. Assuming you have chosen a nice, sunny area, selected a design, and determined that your soil drains properly, you are ready to prepare the soil.

Preparing the Soil

To prepare the soil for a new vegetable garden, first remove large rocks and weeds. Dig out any perennial weeds, especially perennial grasses like Bermuda and quack grass. You need to sift and closely examine each shovelful for every little piece of their roots, or they will regrow with a vengeance. If you are taking up part of a lawn, the sod needs to be removed. If it is a small area, this can be done with a flat spade. Removing large sections, though, warrants renting a sod cutter. Next, when the soil is not too wet, spade over the area.

Most vegetables are heavy feeders, and few soils support them without being supplemented with much organic matter and nutrients. The big-three nutrients are nitrogen (N), phosphorus (P), and potassium (K)—the ones most frequently found in fertilizers. Calcium, magnesium, and sulfur are also important plant nutrients, and plants need a number of trace minerals for healthy growth, among them iron, zinc, boron, copper, and manganese. A soil test is the best way to see what your soil needs. In general, most soils benefit from at least an application of an organic nitrogen fertilizer. While it’s hard to say what your soil needs without a test, the following gives you a rough idea of how much you need per I 00 square feet of average soil.

For nitrogen, apply blood meal at 2 pounds, or fish meal at 2 pounds; for phosphorus, apply 2 pounds bonemeal; for potassium, apply kelp meal according to the package or, in acidic soils, 1½ pounds of wood ashes. Kelp meal also provides most trace minerals. (The addition of so many nutrients will not be needed in subsequent years if composting and mulching are practiced, especially if you rotate your crops and use cover crops.)

After the area is spaded, cover it with 4 or 5 inches of compost, 1 or 2 inches of well-aged manure, and any other needed fertilizers. Add fertilizers by sprinkling them over the soil. If a soil test indicates that your soil is too acidic, lime can be added at this point, though it is best to apply lime in the fall so that it has time to react with the soil before spring planting. Incorporate all the ingredients thoroughly by turning the soil over with a spade, working the amendments into the top 6 to 12 inches. If your garden is large or the soil is very hard to work, you might use a rototiller. (When you put in a garden for the first time, a rototiller can be very helpful. However, research has shown that continued use of tillers is hard on soil structure and quickly burns up valuable organic matter.)

Raked and graded garden bed ready for planting

Finally, grade and rake the area. You are now ready to form the beds and paths. Because of all the added materials, the beds are now elevated above the paths-which further helps drainage. Slope the sides of the beds so that loose soil is not easily washed or knocked onto the paths. Some gardeners add a brick or wood edging to outline the beds. Some sort of gravel, brick, stone, or mulch is needed on the paths to forestall weed growth and to prevent your feet from getting wet and muddy.

The last task before planting your garden is providing support for vining crops like yard-long beans and bitter melon. There are many types of supports, from simple stakes to elaborate wire cages; whichever you choose, installing them before you plant is best.

Starting from Seeds

You can grow all annual vegetables from seeds. They can be started indoors in flats or other well-drained containers, outdoors in a cold frame, or, depending on the time of year, directly in the garden. When I start annual vegetables inside, I seed them in either plastic pony packs that I recycle from the nursery or in compartmentalized Styrofoam containers, variously called plugs and speedling trays (available from mailorder garden-supply houses). Whatever type of container you use, the soil depth should be 2 to 3 inches. Any shallower, and the soil dries out too fast, and deeper soil is usually a waste of seed-starting soil and water.

Starting seeds inside gives your seedlings a safe start away from slugs and birds. It also allows gardeners in cold or hot climates to get a jump on the season. Many vegetables can be started 4 to 6 weeks before the last expected frost date and then transplanted out into the garden as soon as the soil can be worked. Furthermore, some vegetables are sensitive to high temperatures; by starting fall crops inside in mid- or late summer, the seeds germinate and the seedlings get a good start and are ready to be transplanted outside in early fall, when the weather starts to cool.

The cultural needs of seeds vary widely among species; still, some basic rules apply to most seeding procedures. First, whether starting seeds in the ground or in a container, make sure you have loose, water-retentive soil that drains well. Good drainage is important because seeds can get waterlogged, and too much water can lead to damping off, a fungal disease that kills seedlings at the soil line. Commercial starting mixes are usually best because they have been sterilized to remove weed seeds; however, the quality varies greatly from brand to brand and I find most lack enough nitrogen, so I water with a weak solution of fish emulsion when I plant the seeds, and again a week or so later.

Smooth the soil surface and plant the seeds at the recommended depth. Information on seed depth is included in “The Encyclopedia of Asian Vegetables” as well as on the back of most seed packages. Pat down the seeds and water carefully to make the seed bed moist but not soggy. Mark the name of the plant and variety and the date of seeding on a plastic or wooden label and place it at the head of the row. When starting seeds outside, protect the seed bed with either floating row covers or bird netting to keep out critters. If slugs and snails are a problem, circle the area with hardwood ashes or diatomaceous earth to keep them away and go out at night with a flashlight to catch any that cross the barrier. If you start seeds in containers, put the seedling tray in a warm, but not hot, place to help seeds germinate more quickly.

When starting seeds inside, once they have germinated, it’s imperative that they immediately be given a high-quality source of light; otherwise, the new seedlings will be spindly and pale. A greenhouse, sun-porch, or south-facing window with no overhang will suffice, provided it is warm. If such a place is not available, use fluorescent lights, which are available from home-supply stores and specialty mail-order houses. The lights are hung just above the plants for maximum light (no farther than 3 or 4 inches away, at most) and moved up as the plants get taller. Another option I use if the weather is above 60°F is to put my seedling trays outside on a table in the sun and protect them with bird netting during the day, bringing them in at night.

Once seedlings are up, keep them moist and, if you seeded thickly and have crowded plants, thin some out. It’s less damaging to do so with small scissors. Cut the little plants out, leaving the remaining seedlings an inch or so apart. Do not transplant your seedlings until they have their second set of true leaves (the first leaves that sprout from a seed are called seed leaves and usually look different from the later true leaves). If the seedlings are tender, wait until all danger of frost is past before you set them out. In fact, don’t put out heat-loving melons and peppers until the weather is thoroughly warmed up and stable. Young plants started indoors should be hardened off before they are planted in the garden—hat is, they should be put outside in a sheltered place for a few days in their containers to let them get used to the differences in temperature, humidity, and air movement outside. A cold frame is perfect for hardening off plants.

Transplanting

Before setting transplants out in the garden, check to see if a mat of roots has formed at the bottom of the root ball. Open it up so the roots won’t continue to grow in a tangled mass. I set the plant in the ground at the same height as it was in the container, pat the plant in place gently by hand, and water in each plant well to remove air bubbles. I space plants so that they won’t be crowded once they mature; when vegetables grow too close together, they become prone to rot diseases and mildew. If I’m planting on a very hot day or the transplants have been in a protected greenhouse, I shade them by placing a shingle or such on the sunny side of the plants. I then install my irrigation ooze tubing (see Watering and Irrigation Systems, page 93) and mulch with a few inches of organic matter. I keep the transplants moist but not soggy for the first few weeks.

Mulching

Mulching reduces moisture loss, prevents erosion, controls weeds, and minimizes soil compaction. When the mulch is an organic material, it adds nutrients and organic matter to the soil as it decomposes, making heavy clay more porous and helping sandy soil retain moisture. Organic mulches include finished compost from your compost pile, grass clippings, pine needles, composted sawdust, straw, and the many agricultural byproducts like rice hulls and apple and grape pomace. Layers of black-and-white newspaper are particularly good at deterring weeds. Coarse, woody mulches, such as wood and bark chips and shredded bark, do not work well as mulches in vegetable gardens, as they break down slowly and take nitrogen from the soil. However, they do make good mulches for pathways and other areas of a more permanent nature.

Mulch using black plastic

Among the many benefits of mulching is the moderation of soil temperatures. A thick organic mulch helps keep roots from getting too hot in hot summer regions and a black plastic mulch warms soil in cool regions in preparation for spring transplanting. A variation on black plastic, in red and green, called IRT (Infra-Red Transmitting) is on the market. It has the heat-transmit-ting qualities of clear plastic—in other words, it warms soil even more than regular black plastic and also discourages weed growth (which clear plastic does not). The red and green IRT is available from garden supply stores and mail-order garden-suppliers. When you remove the plastic mulches, dispose of them. These plastics don’t decompose, although there are some brands that claim to; it is more likely that they degrade into small pieces.

Composting

Compost is the humus-rich result of the decomposition of organic matter, such as leaves and garden trimmings. The objective of maintaining a composting system is to speed up decomposition and centralize the material so you can gather it up and spread it where it will do the most good. Compost’s benefits include providing nutrients to plants in a slow-release, balanced fashion; helping break up clay soil; aiding sandy soil to retain moisture; and correcting pH problems. On top of that, compost is free, it can be made at home, and it is an excellent way to recycle yard and kitchen wastes. Compost can be used as a soil additive or a mulch.

There need be no great mystique about composting. To create the environment needed by the decay-causing microorganisms that do all the work, just include the following four ingredients, mixed well: 3 or 4 parts brown material high in carbon, such as dry leaves, dry grass, and even shredded black-and-white newspaper; one part green material high in nitrogen, such as fresh grass clippings, fresh garden trimmings, barnyard manure, and kitchen trimmings like pea pods and carrot tops; water in moderate amounts, so that the mixture is moist but not soggy; and air to supply oxygen to the microorganisms. Bury the kitchen trimmings within the pile so as not to attract flies. Cut up any large pieces of material. Exclude weeds that have gone to seed and noxious perennial weeds such as Bermuda grass, because they can lead to the growth of those weeds in the garden. Do not add meat, fat, diseased plants of any kind, woody branches, or cat or dog manure.

A three-bin composting system

I don’t stress myself about the proper proportions of compost materials, as long as I have a fairly good mix of materials from the garden. If the decomposition is too slow, it is usually because the pile has too much brown material, is too dry, or needs air. If the pile smells, there is too much green material or it is too wet. To speed decomposition, I often chop or shred the materials before adding them to the pile and I may turn the pile occasionally to get additional oxygen to all parts. During decomposition, the materials can become quite hot and steamy, which is good; however, it is not mandatory that the compost become extremely hot.

You can make compost in a simple pile, in wire or wood bins, or in rather expensive containers. The size should be about 3 feet high, wide, and deep (3 cubic feet) for the most efficient decomposition and so the pile is easily workable. It can be larger, but too much so and it becomes hard to manage. In a rainy climate, it’s a good idea to have a cover for the compost. I like to use three bins. I collect the compost materials in one bin, have a working bin, and when that bin is full, I turn the contents into the last bin, where it finishes its decomposition I sift the finished compost into empty garbage cans so it does not leach its nutrients into the soil. The empty bin is then ready to fill again.

Watering and Irrigation Systems

There is no easy formula for determining the correct amount or frequency of watering. Proper watering takes experience and observation. In addition to the specific watering needs of individual plants, the amount of watering required depends on soil type, wind conditions, and air temperature. To water properly, you must learn how to recognize water-stress symptoms (often a dulling of foliage color as well as the better-known symptoms of drooping leaves and wilting), how much to water (too much is as bad as too little), and how to water. Some general rules are:

1. Water deeply. Except for seed beds, most plants need infrequent deep watering rather than frequent light sprinkling.

2. To ensure proper absorption, apply water at a rate slow enough to prevent runoff.

3. Do not use overhead watering systems when the wind is blowing.

4. Try to water in the morning so that foliage has time to dry off before nightfall, thus preventing some disease problems. In addition, because of the cooler temperature, less water is lost to evaporation.

5. Test your watering system occasionally to make sure it covers the area evenly.

6. Use methods and tools that conserve water. When using a hose, use a nozzle or watering wand that shuts off the water while you move from one container or planting bed to another. Soaker hoses, made of canvas or recycled tires, and other ooze and drip-irrigation systems apply water slowly and use water more efficiently than do overhead systems.

Drip- or the related ooze- and trickle irrigation systems are advisable wherever feasible, and most gardens are well suited to them. Drip systems deliver water one drop at a time through spaghetti-like emitter tubes or plastic pipe with emitters that drip water right onto the root zone of each plant. Because of the time and effort involved in installing one or two emitters per plant, drip systems work best for permanent plantings. The lines require continual maintenance to make sure the individual emitters are not clogged.

Similar systems, called ooze systems, deliver water through holes made every 6 or 12 inches along solid flexible tubing or ooze along an entirely porous hose. Both of these systems work well in vegetable gardens. Neither system is as prone to clogging as are drip emitters. The solid type is made of plastic and is often called laser tubing. It is pressure compensated, which means the flow of water is even throughout the length of the tubing. The high-quality brands have a built-in mechanism to minimize clogging and are made of tubing that will not expand in hot weather and, consequently, pop off its fittings. (Some of the inexpensive drip-irrigation kits can make you crazy!)

The porous hose types are made from recycled tires and come in two sizes—a standard hose diameter of 1 inch, great for shrubs and trees planted in a row, and ¼-inch tubing that can be snaked around beds of small plants. Neither are pressure compensated, which means the plants nearest the source of water get more water than those at the end of the line. It also means they do not work well if there is any slope.

All types of drip emitter and ooze systems are installed after the plants or seeds are in the ground and are held in place with ground staples. To install any such system, you must also install an antisiphon valve at the water source to prevent dirty garden water from being drawn up into the house’s drinking water. Further, a filter is needed to prevent debris from clogging the emitters. To set up the system, 1-inch distribution tubing is connected to the water source and laid out around the perimeter of the garden. Then smaller-diameter drip and ooze lines are connected to this. As you can see, installing these systems requires some thought and time.

You can order these systems from specialty mail-order garden and irrigation sources or by visiting your local plumbing-supply store. I find the latter to be the best solution for all my irrigation problems. Over the years, I’ve found that plumbing-supply stores offer professional-quality supplies, usually for less money than the so-called inexpensive kits available in home-supply stores and some nurseries. In addition to excellent materials, the professionals there help you to lay out an irrigation design tailored to your garden. Whether you choose an emitter or an ooze system, when you go to buy your tubing, be prepared by bringing a rough drawing of the area to be irrigated—with dimensions, the location of the water source and any slopes, and, if possible, the water pressure at your water source. Let the professionals walk you through the steps and help pick out supplies that best fit your site.

Problems aside, all forms of drip and ooze irrigation are more efficient than furrow or standard overhead watering with respect to delivering water to its precise destination; they are well worth considering. They deliver water slowly, so it doesn’t run off. They also water deeply, which encourages deep rooting. They also eliminate many disease problems, and because so little of the soil surface is moist, there are fewer weeds. Finally, they have the potential to waste a lot less water.

Weeding

Weeding is needed to make sure unwanted plants don’t compete with and overpower your vegetables and herbs. A small triangular hoe will help you weed a small garden if you start when the weeds are young and easily hoed. If you allow the weeds to get large, a session of hand pulling is needed. Be cautious, as many plants are shallow rooted. Applying a mulch is a great way to cut down on weeds; however, if you have a big problem with slugs in your garden, the mulch gives them more places to hide. Another means of controlling weeds, especially annual weeds like crabgrass and pigweed, is a new organic preemergence herbicide made from corn gluten called Concern Weed Prevention Plus. This gluten meal inhibits the tiny feeder roots of germinating weed seeds so they wither and die. It does not kill existing weeds. Obviously, if you use it among new seedlings or in seed beds, it kills the vegetables too, so it is only useful in areas away from very young plants.

Crop Rotation

Rotating crops in an edible garden has been practiced for centuries. The object is to avoid growing members of the same family in the same spot year after year, as plants in the same family are often prone to the same diseases and pests and deplete the same nutrients. For example, peppers should not follow eggplants or tomatoes, as all are Solanaceae-family plants and all are prone to fusarium wilt. On the other hand, in southeastern gardens, quick-growing cabbage-family plants, such as mustard, make a great crop to rotate with peppers as they discourage the root knot nematodes to which many peppers are susceptible.

Crop rotation is also practiced to help maintain the soil nutrient level. The pea family (legumes), which includes not only peas and beans but also clovers and alfalfa, adds nitrogen to the soil. In contrast, most members of the cabbage, cucumber, and tomato families deplete the soil of nitrogen. Because most vegetables deplete the soil, knowledgeable gardeners not only rotate their beds with vegetables from different families, they also include an occasional cover crop of clover or alfalfa (or other legume) and other soil benefactors, such as buckwheat. After growing for a few months, these crops are turned under, providing organic matter and many nutrients. Some cover crops (like rye) are grown over the winter to control soil erosion. The seeds of all sorts of cover crops are available from farm suppliers and specialty seed companies.

The following is a short list of related vegetables and herbs. The plants listed for each family are not comprehensive; they are examples of the plants in that family.

Apiaceae (parsley and carrot family)—includes carrots, celeriac, celery, chervil, coriander (cilantro), dill, fennel, lovage, parsley, parsnips

Asteraceae (sunflower and daisy family, also called composites)—includes artichokes, calendulas, celtuce, chicories, dandelions, endives, lettuces, marigolds, tarragon

Brassicaceae (mustard and cabbage family)—includes arugula, broccoli, cabbages, cauliflower, collards, cresses, kale, kohlrabi, komatsuna, mizuna, mustards, radishes, turnips

Chenopodiaceae (goosefoot family)—includes beets, chard, orach, spinach

Cucurbitaceae (cucumber or gourd family)—includes cucumbers, gourds, melons, summer squash, winter squash, pumpkins

Fabaceae (pea family, also called legumes)—includes beans, cowpeas, fava beans, lima beans, peanuts, peas, runner beans, soybeans, sugar peas

Lamiaceae (mint family)—includes basil, mints, oregano, rosemary, sages, summer savory, thymes

Liliaceae (lily family)—includes asparagus, chives, garlic, leeks, onions, Oriental chives, shallots

Solanaceae (nightshade and tomato family)—includes eggplants, peppers, potatoes, tomatillos, tomatoes

Floating Row Covers

Among the most valuable tools for plant protection in the vegetable garden are floating row covers made of lightweight spun-bond polyester or polypropylene fabric. They are laid directly over the plants, where they “float” in place, though they can also be stretched over hoops. These covers can be used to protect plants against cold weather and to shade them in extremely hot and sunny climates.

If used correctly, row covers are a most effective pest control for various beetles and caterpillars, leafhoppers, aphids, and leaf miners. The most lightweight covers, usually called summerweight or insect barriers because they generate little heat buildup, can be used throughout the season for insect control in all but the hottest and coldest climates. They cut down on 10 percent of the sunlight, which is seldom a problem, unless your garden is already partly shady. Heavier versions, sometimes called garden covers under trade names including Reemay and Tufbell, variously cut down from 15 percent to 50 percent of the sunlight—which could be a problem for some plants, such as peppers—but they also raise the temperature underneath from 2°F to 7°F, which can help to protect plants from early fall frosts and to extend the season in cool-summer areas. Another way to raise the temperature is to use two layers of the lightweight cover.

Floating row cover

Other advantages to using floating row covers include:

*The stronger ones protect plants from most songbirds, though not from crafty squirrels and blue jays.

* They raise the humidity around plants, a bonus in arid climates but a problem in humid climates.

* They protect young seedlings from sunburn in summer and in high-altitude gardens.

There are a few limitations to consider:

* These covers keep out pollinating bees needed to produce squash and cucumbers.

* Many of the fabrics last only a year and then start to deteriorate. (I use tattered small pieces to cover containers, in the bottoms of containers to keep out slugs, etc.)

* Row covers use petroleum products and eventually end up in the landfill.

* In very windy areas, tunnels and floating row covers are apt to be blown away or become shredded.

* The heavyweight versions may cut down on too much light and are useful only to help raise temperatures when frost threatens.

Rolls of the fabric, from 5 to 10 feet wide and up to 100 feet long, can be purchased from local nurseries or ordered from garden-supply catalogs. As a rule, mail-order sources offer a wider selection of materials and sizes.

Before you apply your row cover for pest protection, fully prepare the bed and make sure it’s free of eggs, larvae, and adult pests. Then install drip irrigation, if you are using it, plant your crop, and mulch (if appropriate). There are two ways to lay a row cover: directly on the plants or stretched over wire hoops. Laying the cover directly on the plants is the easier approach. However, laying it over hoops makes it easier to check underneath. Also, some plants are sensitive to abrasion; if the wind whips the cover around, the tips of the plants may turn brown. When you lay the fiber directly on the plants, leave some slack so plants have room to grow. For both methods, secure the edges completely with bricks, rocks, old pieces of lumber, bent wire hangers, or the U-shaped metal pins sold for this purpose.

To avoid pitfalls, it’s critical to check under the row covers from time to time. Check soil moisture; the fibers sometimes shed rain and overhead irrigation water. Check as well for weeds; the protective fiber aids their growth too. Most important, check for insect pests that may be trapped inside.