Below is the Text of the Teachers Guide By Lila Ralston and Catherine Little
A SQUARE YARD IN THE SCHOOL YARD
For more Square Foot Information after you read this Guide click here
We welcome you and your students to Square Foot Gardening. This kit is designed for those with no gardening experience at all; experienced gardeners may already know much of this material.
A WORD ABOUT GARDENING METHODS
Gardeners, and especially gardening authorities, have a strange tendency to sound as if they have discovered the One True Way. Please take this with a grain of salt. This guide is based on Mel Bartholomew's Square Foot Gardening, a book and method we feel is well-suited to school garden projects. This does not mean there is no other source of useful garden information. If you see information that conflicts with what you read here, don't worry. There are many ways to garden; experiment with new ideas and different ways of doing things. From time to time you will need detailed information on varieties of plants, pest control, composting, etc. There are many excellent books and magazines on the market and in your local library. We regard their authors as colleagues, not competitors. If two authors disagree about the best way to do something, try both methods and see which works best for you (an excellent science activity!).
What is the Square Foot Method?
How to Start Your Square Foot Garden
Deciding what to plant
When to plant
Seed starting vs. transplants
Caring for your garden
Tips to Remember
Weeds, pests and diseases
Plants Recommended for Beginners
What to Grow if your Garden is Too (Something)
Sources for seeds adapted to specific areas
Diagrams --- hit your back button to get back here from the Diagram.
Construction of block frame
Construction of square foot dividers
Construction of raised bed frame
Wheel chair garden
Construction of trellis
Soil preparation procedure
WHAT IS THE SQUARE FOOT METHOD?
Square foot gardening is a method that sets plants in a grid pattern rather than in rows with spaces left between. The basic unit is a block, three feet by three feet or four feet by four feet, that is further divided into one-foot squares. Each block is surrounded by paths on all four sides. The gardener steps only on the paths, so the soil does not become packed down.
Because plants are spaced closer together in the square foot method, the condition of the soil is especially important. It must be deep, loose, and well-cultivated, with plenty of organic matter to provide nutrients and allow air and water to reach the plants' roots.
When a square is harvested, new seeds or transplants are planted immediately. This allows for steady production throughout the season, maximizing your harvest. A square may contain from one to sixteen plants, depending on each crop's requirements; a chart of suggested spacings for common plants is included in this kit.
Annual: A plant that completes its life cycle, from seedling to seed-producing maturity, in one year.
Biennial: A plant that takes two years to grow from a seedling to maturity.
Block: As used in SFG, a square area of garden small enough that all parts can be reached comfortably without stepping or leaning on the soil. Gardens for adults and older children are based on four-foot by four-foot blocks; those for younger children, on three-foot by three-foot blocks.
Compost: Organic matter that has been broken down by the action of bacteria, fungi, and other organisms. It contains some nutrients, but its most important effect on your garden is to improve the texture of your soil and allow it to hold more air and water.
Cubic Foot: A volume equal to a cube 1 foot wide by 1 foot high by 1 foot deep. Also equals about 7 1/2 gallons.
Diatomaceous Earth: A powder made of the glassy skeletons of diatoms (microscopic marine organisms), d.e. is used to kill or repel slugs and insects. Although d.e. has millions of microscopic spikes that can pierce an insect's shell, it is harmless to humans; it has even been used as an abrasive in toothpaste! Be careful not to breathe it, though; like any dustlike substance, it can irritate your respiratory system.
Direct Seeding: Planting seeds directly in the place you want the plant to grow, as opposed to starting them in one place and transplanting them later.
Fork: A garden fork, a four-tined implement used for loosening soil.
Mulch: Any material used to cover the soil surface. Mulch prevents weeds from sprouting, retains moisture, and helps keep the soil moist. It can also insulate the soil, keeping it cool in hot weather. Don't put on mulch too early in the spring; it keeps the soil from warming up. Possible materials for mulch are hay, pine straw, layers of newspaper, old carpet, plastic sheeting, etc.
Organic Matter: Decayed or partially decayed remains of plants or animals. Except for manure, blood meal and bone meal, don't use animal products, e.g. meat scraps, in your garden or compost. Also, do not use dog or cat droppings; they are a disease and parasite hazard.
Peat moss: Dried sphagnum moss, a bog plant. Peat moss is an excellent source of organic matter to add to your soil.
Perennial: A plant that will live for more than two years, producing seeds each year. Some plants, such as tomatoes, are perennials in their native habitat but are treated as annuals in temperate climates because they can't survive the winter.
Raised Beds: Essentially, large bottomless containers filled with soil that rest on the ground. If your soil is rocky, very infertile, or poorly drained, you can make your blocks into raised beds by building the frame 12 inches or more deep (see diagram).
Seed Starting: Growing transplants for later planting in the garden.
Seedlings: Plants that have recently sprouted from seeds. When they are big enough to move out to the garden, they're called transplants.
Spade: A shovel with a flat blade and a square tip. Preferable (for Square Foot Gardening) to a curved shovel with a pointed tip because it allows you to dig a straight-sided, flat-bottomed hole.
Square: As used in SFG, a one-square-foot portion of your garden.
Tiller: A powered garden machine for cultivating soil. In your Square Foot Garden you will need a tiller for one day a year at most. Rent or borrow one, or use a spade and fork instead.
Transplants: Young plants that are ready to be moved out into the garden. You can purchase transplants or, if you have a suitable location, start your own from seed in the late winter or early spring.
Trowel: A hand implement for digging. If you can bend a trowel, it's no good. This is the tool you will use the most; try to get a good sturdy one.
Vermiculite: A form of the mineral mica that has been heated until it expands (similar to the way popcorn pops). Vermiculite is extremely light and can hold water like a sponge. It does not decompose so it lasts many years in the garden.
HOW TO START YOUR SQUARE FOOT GARDEN
In selecting a location for your garden, try to choose a spot that is reasonably level, receives at least six to eight hours of sun per day, has decent soil, is well drained, and is convenient to your classroom and to a water source. Do not locate your garden in a depression or at the foot of a slope; you will have drainage problems (and frost problems, if you live where there is frost). If you must choose between several sites, remember that the condition of the soil is the easiest of these factors to change.
Once you have chosen your site, make a frame to mark off the garden area and contain the growing soil. We recommend a frame of 2x4 or 2x6 lumber, which can often be obtained free from contractors who have some left over. Make the frame 3 feet by 3 feet for young children (up through fifth grade); 4 feet by 4 feet for older children and adults. This ensures that the gardeners can reach all parts of the block easily.
Next, mark off the area where the frame will be placed. Remove the sod and compost it. Cultivate the soil to loosen it to a depth of 12 inches or more. You may want to rent or borrow a tiller, or use a heavy-duty spade and fork. This initial cultivation may be hard work, but it only has to be done once. (In subsequent seasons you will only need to loosen the already-cultivated soil; a fork or a spade and fork will work nicely for this.)
After loosening the soil, assemble your wood frame. Then put in 4 cubic feet of Mel's Mix: equal parts of vermiculite, compost and peat moss. (Coarse vermiculite is preferable to fine vermiculite; nurseries often sell the coarse grade in 4 cu.ft. packages, which are much cheaper than the smaller packages you find elsewhere.) Work this into the soil thoroughly, being sure to break up any clods and remove rocks, sticks and other debris.
Your block will need paths around the outside (at least two feet wide). Paths may be made of lumber, wood chips, gravel, grass (which must be mowed), or any other material that will keep your feet clean and will look tidy. You will also need some kind of divider to make a clear division between the individual one-foot squares. A rigid frame made of 1/4" by 3/4" wood strips connected by bolts works well. Paint it white so it will last longer and show up better. This will really make the square-foot organization clear and will give you a visually stunning garden. Other possibilities for the dividers are vinyl-coated clothesl ine stapled or nailed to the frame of the block; and bamboo poles lashed together (in areas where bamboo grows, you can often get it free). If you can't get the specific materials mentioned here, scout your area for workable substitutes. The main things to keep in mind are plenty of organic matter for your soil; a sturdy border around each block; clean, uncluttered paths; and neat, clearly visible dividers to mark off individual square feet.
Once you have your garden set up, you will need a supply of compost for use throughout the growing season. Each time you harvest and replace a plant, you'll add compost to keep the soil from becoming exhausted. Compost is expensive to buy but easy to make: if you don't have a compost bin or pile, start one!
During the gardening season, the only tools you will need are a trowel, a bucket, and a cup. You'll be using the bucket to carry water, so be sure it's not too heavy to carry when full. Extra buckets and trowels are helpful if many people will be gardening at the same time.
Deciding What to Plant
When deciding what to plant in each square foot, keep the following in mind. First, the quantity you plant should depend on how much you want to harvest and when (all at once or over an extended period). Second, don't let tall crops block the sun from reaching shorter ones (unless the shorter crop needs shade). Third, if you are growing large plants such as corn, melons, or tomatoes, look for smaller, more compact varieties. These are especially well suited to the square foot garden.
These considerations, plus figuring out the time between planting and harvest, how many plants of a given kind will fit in a given space, and which side of the garden the sunlight is coming from, will provide your students practice in math, geometry, and conflict resolution! If possible, assign each child his or her own square foot. If necessary, a team of children can share a square, or children can grow fast-maturing crops and garden in relays. We have included more detailed curriculum ideas at the end of this guide.
When to Plant
Consult your local extension agent for the date of your average last spring frost. Planting recommendations on seed packets, in catalogs, and in garden books and magazines are based on this date (and/or on the date of your first autumn frost).
Seed Starting vs. Transplants
The fact that the school year ends just as the gardening season reaches full swing poses a special problem for school gardeners. Using purchased transplants can enable you to harvest some crops before school ends even in the northern zones of the U.S. Still, seed starting gives children (and adults!) a particular sense of accomplishment. If you have suitable indoor space and lighting, we recommend starting at least some of your plants from seed. In addition, try some fast-growing crops that can be direct-seeded outdoors, such as peas and beans.
If you need transplants but your budget is inadequate to buy them, ask for volunteers who can start seeds at home for you during the winter. This makes a good project for a child to report on in class; it may also interest parents in helping with your garden project in other ways.
Although seeds are less expensive than transplants (for the same number of plants), seed prices can vary widely. It pays to look at several catalogs and retail sources to find the best price for the seeds you want. In some parts of the country, hardware stores sell seeds of non-patented varieties (usually "old standards" that have been popular for many years) for ten cents a packet or less. Be sure they are dated for the current year! Some seeds lose viability rapidly and last year's seeds may not be a bargain at any price.
Caring for Your Garden
Caring for your garden involves three main tasks: watering, pest control, and harvesting. The most important factor for success in all three tasks is frequent, careful observation of your garden. If you inspect each square carefully every day (or at least every school day), you can water the plants before they suffer from drought stress; you can spot pest problems before they get out of hand; and you can harvest your crops at their best. Putting off any of these tasks for a week or two can invite disaster. Withered seedlings, insect-riddled leaves, and mushy, dachshund-sized zucchini will certainly make an impression on your students, but not a pleasant one.
Water your plants by pouring water from a cup onto the soil at the base of the plant; not on the leaves. Wet leaves are vulnerable to disease, and besides, it's the roots that need the water. Do not overwater! If the soil is still damp, wait until it is dry an inch or two below the surface before watering again. Likewise, be sure you water deeply enough to dampen the soil several inches below the surface. Watering too shallowly will encourage your plants to form roots mainly at the surface, which will make them vulnerable to drought.
Pest control: if you see an insect in your garden, observe it to see if it's damaging your plants. Most insects are beneficial, acting as pollinators or preying on pests. Caterpillars and slugs are two exceptions to this rule; they're easy to identify and they'll eat you out of house and home. Pick them off and get rid of them. We do not recommend using chemical pesticides, especially with young gardeners. If hand-picking pests doesn't take care of the problem, try one of the organic pest-control products such as diatomaceous earth.
Harvesting: If you are not an experienced gardener, consult gardening or cooking magazines or books for advice on when to harvest the crops you are growing. Many crops, such as lettuce, can be harvested at almost any stage during their growth; others, such as peas, have a fairly narrow "window of opportunity" during which they are at their best. This is also useful information to have when you buy produce grown by someone else!
The off-season: If it's not possible for someone to tend your garden during the summer, you can either mulch it heavily with something that will decompose (like shredded leaves), or plant a cover crop (like clover, buckwheat, alfalfa or vetch). Either of these will keep the soil from compacting and add organic matter while keeping down weeds. If someone can check on the garden periodically you could try growing a low-maintenance crop like squash, pumpkins, ornamental corn or popcorn. This will give you something to look forward to in the fall!
Here are some spacing recommendations for a basic Square Foot Garden. For information on growing plants on trellises, in trenches, or under frost protection, consult Square Foot Gardening or "Ten New Square Foot Garden secrets" in Organic Gardening, February 1996.
One plant per square foot (12 inches apart): peppers, "patio" (dwarf bush) tomatoes, potatoes, broccoli, cabbage, cauliflower, kale, head lettuce, New Zealand spinach, peppers, peanuts, potatoes, large sunflowers, tampala (amaranth)
Four plants per square foot (6 inches apart): leaf lettuce, parsley, Swiss chard, sweet corn (small varieties), mustard greens, basil, coriander, dill, parsnips, shallots, small sunflowers, turnips
Nine plants per square foot (4 inches apart): bush beans, spinach, leeks, anise, chervil, corn salad (mache), mustard greens, nasturtiums
Sixteen plants per square foot (3 inches apart): carrots, beets, radishes, onions, cumin, garden cress
For plants not on this list, look on the seed packet and find the recommended spacing after thinning. Ignore the space called for between rows. For example, if the directions say "Thin to six inches apart in rows two feet apart," space plants six inches apart in every direction, i.e., four per square foot.
TIPS TO REMEMBER
PLANTS RECOMMENDED FOR BEGINNERS
The plants on this list are easy to grow in most places in the continental U.S. If your garden has special problems, see the next section. We have concentrated mainly on plants that don't need a great deal of space or special structures like trellises. If you have a trellis or a fence, you may want to try pole beans, cherry tomatoes (The Plant that Would Not Die!), squash, hyacinth bean (Dolichos lablab), morning glories, or balloon vine (Cardiospermum halicacabum, also called love-in-a-puff).
Vegetables and Herbs: Asparagus (perennial), basil, beans, beets, carrots, chives (perennial), corn, corn salad (also called mache or lamb's lettuce), dill, garden cress (also called peppergrass), horseradish (perennial), Jerusalem artichoke (perennial; also called sunchoke), leaf lettuce, peas, potatoes, radishes, rutabagas, salsify, snow peas, Swiss chard, turnips.
Flowers: Bachelor's buttons (Centaurea cyanus, also called ragged-robins), California poppies (Eschscholzia californica), calliopsis (Coreopsis tinctoria), cosmos, marigolds, nasturtiums, sunflowers.
WHAT TO GROW IF YOUR GARDEN IS TOO (SOMETHING)
Almost any garden problem can be improved over time, but if conditions in your garden are less than ideal and you want to grow something RIGHT NOW, here are some ideas.
TOO COLD: Snowpeas, kale, rhubarb and spinach are the ultimate cold-season crops. Other good contenders are the brassicas: broccoli, cauliflower, cabbage, turnips, brussels sprouts and radishes. Carrots and beets like cool weather. For flowers, try calendula, snapdragons, larkspur, pansies, violas, stock, Chinese forget-me-nots, sweet alyssum, baby blue eyes, sweet peas, and California poppies. Raised beds will help the soil warm up; so will dark-colored mulch applied after the warming process has begun. You may also want to consider using cold frames, plastic tunnels, or other "season extenders".
TOO HOT: Hot peppers, okra, cowpeas, corn, peanuts, pumpkins, squash, sweet potatoes, watermelon and tomatoes are all heat-loving crops. Flowers that do well in heat are salvia (sage), yarrow, marigolds, petunias, zinnias, coreopsis, verbena, portulaca, cosmos, and sunflowers. Gourds also like heat and are easy to grow. A thick mulch is helpful; it cools the soil and the roots of the plants, and helps retain water. Using shade cloth, or planting tall crops to cast some shade on shorter ones during the afternoon, can also help.
TOO DRY: Many herbs are drought-resistant once they reach full size. Drought-tolerant flowers include lamb's ears, alyssum, violets, bachelor's buttons, and zinnias. For a drought-tolerant vegetable, try tepary beans; they are native to the Southwest and have deep root systems. Compost helps the soil hold more water; a thick layer of mulch slows down evaporation.
TOO WET: Lots of moisture is seldom a problem unless drainage is poor. Very few plants will tolerate "wet feet" and most of those that will are perennials. Try Siberian iris, cardinal flower, ox-eye daisies, elderberry (a small tree), mint (warning: it can take over the entire garden), garden cress, or watercress (for really wet areas, i.e. stream banks). Bad drainage is difficult to correct; raised beds are one possible answer to this problem. Adding sand and/or lots of compost may help, too.
TOO ACIDIC: Most plants do fine in slightly acidic soil. The champion acid-tolerant plants are fennel; blueberry and its annual relative, garden huckleberry (Solanum nigrum), and potatoes. Other plants that will tolerate moderately acid soil are sweet potatoes, shallots, watermelon, tomatoes, radishes and marjoram. Adding lots of compost may help tone down the acidity of your soil; lime and wood ashes are helpful for very acidic soil. Ask your county extension agent for help.
TOO ALKALINE: This is a bigger problem than acidity. Asparagus, beets, lentils, broccoli, lettuce, onions, cauliflower, celery and muskmelons will grow in slightly alkaline soil. Flowers and herbs that tolerate some alkalinity include alyssum, larkspur, candytuft, dianthus, thyme, savory, and nasturtiums. If your soil is very alkaline, you will need to correct the problem with sulfur or other soil amendments. Ask your extension agent for advice.
TOO SANDY: Many of the common herbs used in cooking originated in the Mediterranean area and do quite well in sandy soil. In addition strawberries, beets, Swiss chard, New Zealand spinach, potatoes, carrots, rutabagas and radishes do well in sandy soil if compost is added. Beans, peanuts, chives, nasturtiums and sweet potatoes will grow in sandy soil as well. Adding lots of compost will help sandy soils hold more water and nutrients. TOO HARD: If you have clay, adobe, or caliche soil you may need to add considerable organic matter to enable seeds to sprout and air and water to move through the soil. Until you get it into shape, try broccoli, cabbage, cauliflower or mustard greens grown from transplants. You might also plant some clover as a cover crop (till it under to add organic matter). A thick mulch will keep the surface of the soil from forming a hard crust.
TOO SHADY: Few plants will grow in deep shade, but many of the root and leaf crops will do fine in partial shade, especially in hot weather. Peas, beans, leeks, and summer squash will tolerate some shade. For flowers, try foxglove, coleus, impatiens, and violets. Herbs that will grow in partial shade include lemon balm, lemon verbena, mints (warning! mints will take over your garden!), chives, sweet woodruff, thyme, sage, dill, parsley, and basil. Sometimes you can improve a shady problem area by trimming branches to admit more sun, or by using a light-colored wall or light-colored mulch to reflect more light onto the plants.
TOO SALTY: A vexing problem. If you live near the ocean, however, the availability of seaweed, an excellent mulch, almost makes up for the salt problem (rinse seaweed in fresh water before using it as mulch). Asparagus, potatoes and many herbs are salt-tolerant. Shallow rooted crops, such as lettuce and other greens, may do well since their roots stay above the salty groundwater. Raised beds are sometimes helpful.
TOO BIG: Yes, it is possible to have a garden that is too big for the available manpower. Divide the space in half: use one half for your garden plants and the other for a cover crop, such as clover, that can be tilled under to enrich the soil. Then reverse the two the following year. If this doesn't appeal to you, try growing pumpkins. A single plant of a large variety of pumpkin can cover 50 square feet or more, and its huge leaves will shade out the weeds. (It will also deplete your soil, so remember to add lots of compost before planting anything else in that space.)
TOO SMALL: A much more common problem. Grow small plants. Grow plants that mature quickly so you can harvest more than one crop per season. Grow vining plants such as pole beans, cucumbers and tomatoes and train them up a trellis. Plant in containers.
HOPELESS: Some plants will grow just about anywhere. Try cherry tomatoes, Jerusalem artichokes (not an artichoke but a perennial sunflower with edible tubers), peas, beans, radishes, thyme, yarrow, rosemary, daisies, coreopsis or cosmos. You might also try growing in containers.
ALL-PURPOSE ADVICE: Whatever your climate, you can do an end run around poor conditions by growing native plants. Your extension agent can recommend native wildflowers; so can many of the seed catalogs that specialize in wildflowers. The anthropology or horticulture department of the nearest university may be able to point you to plants grown by native peoples in your area. Heirloom varieties of garden plants adapted to your locale are also a good bet. Here are a few sources of seeds adapted to particular areas; check gardening magazines for more sources that fit your particular needs.
Abundant Life Seed Foundation
P.O. Box 772
Port Townsend, WA 98368
($5 for catalog and newsletters)
3950 W. New York Dr.
Tucson, AZ 85745
($1 for catalog; specializes in Native American and heirloom crops)
Southern Exposure Seed Exchange
P.O. Box 158
North Garden, VA 22959
($2 for catalog; many heirloom varieties)
Southern Garden Co.
P.O. Box 200 D-6
10800 Alpharetta Hwy.
Roswell, GA 30076
P.O. Box 2091
Melbourne, FL 32902
($2 for catalog)
Rawlinson Garden Seed
269 College Rd.
Truro, Nova Scotia
B2N 2P6 Canada
($1 for catalog; free to Atlantic Canada, Quebec, and Ontario)
P.O. Box 9107
Moscow, ID 83483
($1 for catalog, refundable with order. Seeds for short seasons or higher elevations)
Johnny's Selected Seeds
305 Foss Hill Rd.
Albion, ME 04910
English or Language Arts
Keep a gardening journal. Exchange letters or e-mail with other schools involved in Square Foot projects (list available from the SFG Foundation). Study the many examples of writing about gardens and gardening: John Gerard, John Parkinson, Gertrude Jekyll, W. B. Yeats, E. B. White, et al. If a plant fails to thrive, use research and deductive reasoning to find out why.
Many kinds of experiments are possible: comparing different varieties, different gardening methods, different fertilizers, etc. Botany, ecology, geology, and decomposition (composting) are all part of a working garden.
Try charting the growth or yield of plants, calculating the number of plants that can be grown in a given area, calculating the area of a particular piece of land, measuring the angle of sunlight, tracking temperature and rainfall, etc.
Study the plants grown by various cultures and their uses. Prepare a meal using foods from the garden. Study the impact of the introduction of plants from one part of the world to another (sugar cane, tea and potatoes all had profound impacts on politics and history).
Study the agricultural history of your area and compare heirloom varieties to modern hybrids, while comparing the agricultural methods used in different eras.
Make leaf rubbings, draw or paint the plants and animals in the garden, grow and use dye plants, press flowers. P.E. Gardening is good exercise! Hauling away rocks, cultivating a new garden spot, and carrying water are particularly recommended (just kidding).
This guide is still being revised. If you have suggestions for improving it, please contact us and we'll include them in the next version!
Lila F. Ralston
164 Merlin Drive
Athens, GA 30606
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