Growing Vegetables In The Home Garden (Part One)
Protecting The Garden
Usually, the garden should be surrounded by a fence sufficiently high and close-woven to keep out dogs, rabbits, and other animals. The damage done by stray animals during a season or two can equal the cost of a fence. A fence also can serve as a trellis for beans, peas, tomatoes, and other crops that need support.
In most sections of the country, rodents of various kinds damage garden crops. In the east, moles and mice cause much injury. Moles burrow under the plants, causing the soil to dry out around the roots. Mice either work independently or follow the burrows made by moles, destroying newly planted seeds and young plants. In the West, ground squirrels and prairie dogs damage vegetable gardens. Most of these pests can be partially controlled with traps.
Soil, Drainage, and Sunshine
Fertile, deep, friable, well-drained soil is necessary for a successful garden. The exact type of soil is not so important as that it be well drained, well supplied with organic matter, retentive of moisture, and reasonably free of stones. The kind of subsoil also is vitally important. Hard shale, rock ledges, gravel beds, very deep sand, or a hardpan under the surface soil is likely to make the development of high-grade garden soil extremely difficult or impossible. On the other hand, infertile soil that has good physical properties can be made productive by using organic matter, lime, commercial fertilizer, and other soil improving materials.
Good drainage of the soil is essential. Soil drainage may often be improved by installing agricultural tile, digging ditches, and sometimes by plowing deep into the subsoil. The garden should be free of low places where water might stand after a heavy rain. Water from surrounding land should not drain into the garden, and there should be no danger of flooding by overflow from nearby streams.
Good air drainage is necessary to lessen the danger of damage by frost. A garden on a slope that has free movement of air to lower levels is most likely to escape late-spring and early-autumn frost damage.
A gentle slope of not more than 1 1/2 percent facing in a southerly direction helps early crops get started. In sections that have strong winds, a windbreak of board fence, hedge, or trees on the windward side of the garden is recommended. Hedges and other living windbreaks should be far enough away from the garden to prevent shade or roots from interfering with the garden crops.
The garden should get the direct rays of the sun all day if possible. Some crops can tolerate partial shade, but no amount of fertilizer, water, or care can replace needed sunshine. Even where trees do not shade garden crops, tree roots may penetrate far into the soil and rob crops of moisture and plant food.
Damage to garden crops by tree roots may be largely prevented by digging a trench 1 1/2 to 2 feet deep between the trees and the garden, cutting all the tree roots that cross the trench. Then put a barrier of waste sheet metal or heavy roofing paper along one wall of the trench and refill it. This usually prevents root damage for several years.
PREPARING THE SOIL back to top
Good soil for growing vegetables must be protected by proper cultivation, use of organic matter, maintenance of soil fertility, and control of plant pests. Properly prepared soil provides a desirable medium for root development, absorbs water and air rapidly, and usually does not crust badly.
Tillage practices do not automatically create good garden soil. Tillage is needed to control weeds, mix mulch or crop residues into the soil, and alter soil structure. Unnecessary tillage increases crusting on the soil surface, and if the soil is wet, tillage compacts it.
Fertility requirements differ between long and short growing seasons and among soil types. In almost every State, the Extension Service will test soils and provide fertilizer recommendations.
Plant pests compete with garden crops and impair their growth. These pests include weeds, insects, fungi, bacteria, viruses, and nematodes. They must be controlled or the garden will not succeed. However, chemical controls must be used carefully to prevent damage to neighboring crops or subsequent crops. When mechanical and chemical controls do not work, crops that are resistant to the pests should be planted in the area for a season or two.
The time and method of preparing the garden for planting depend on the type of soil and the location. Heavy clay soils in the northern sections are frequently benefitted by fall plowing and exposure to freezing and thawing during the winter, but when the garden is cover-cropped, it should not be plowed until early spring. In general, garden soils should be cover-cropped during the winter to control erosion and to add organic matter. Gardens in the dry-land areas should be plowed and left rough in the fall, so that the soil will absorb and retain moisture that falls during the winter. Sandy soils, as a rule, should be cover-cropped, then spring-plowed. Whenever there is a heavy sod or growth of cover crop, the land should be plowed well in advance of planting and the soil disked several times to aid in the decay and incorporation of the material. Land receiving applications of coarse manure either before or after plowing should have the same treatment.
Soils should not be plowed or worked while wet unless the work will certainly be followed by severe freezing weather. Sandy soils and those containing high proportions of organic matter - peats and mucks for example - bear plowing and working at higher moisture content than do heavy clay soils. The usual test is to squeeze together a handful of soil. If it sticks together in a ball and does not readily crumble under slight pressure by the thumb and finger, it is too wet for plowing or working. When examining soil to determine if it is dry enough to work, samples should be taken both at and a few inches below the surface. The surface may be dry enough, but the lower layers too wet, for working. Soil that sticks to the plow or to other tools is usually too wet. A shiny, unbroken surface of the turned furrow is another indication of a dangerously wet soil condition.
Fall-plowed land should be left rough until spring, when it may be prepared by disking, harrowing, or other methods. Spring-plowed land should be worked into a suitable seedbed immediately after plowing. Seeds germinate and plants grow more readily on a reasonably fine, well-prepared soil than on a coarse, lumpy one, and thorough preparation greatly reduces the work of planting and caring for the crops. It is possible, however, to overdo the preparation of some heavy soils. They should be brought to a somewhat granular rather than a powdery-fine condition for planting. Spading instead of plowing is sometimes advisable in preparing small areas, such as beds for extra-early crops of lettuce, onions, beets, and carrots.
Organic matter improves soil as a growing medium for plants. It helps release nitrogen, minerals, and other nutrients for plant use when it decays. A mulch of partially rotted straw, compost, or undecomposed crop residue on the soil helps keep the soil surface from crusting, retards water loss from the soil, and keeps weeds from growing.
Practically any plant material can be composted for use in the garden. Leaves, old sod, lawn clippings, straw, and plant refuse from the garden or kitchen can be used. Often, leaves can be obtained from neighbors who do not use them or from street sweepings.
The purpose of composting plant refuse or debris is to decay it so that it can be easily worked into the soil and will not be unsightly when used in the garden. Composting material should be kept moist and supplied with commercial fertilizer, particularly nitrogen, to make it decay faster and more thoroughly.
The usual practice in building a compost pile is to accumulate the organic material in some out-of-the-way place in the garden. It can be built on open ground or in a bin made of cinder blocks, rough boards, or wire fence. The sides of the bin should not be airtight or watertight. A convenient time to make a compost pile is in the fall when leaves are plentiful (fig. 1).
Figure 1 - Making a new compost pile.
In building the compost pile, spread out a layer of plant refuse about 6 inches deep and add one-half pound or one cupful of 10-10-10, 10-20-10, or 10-6-4 fertilizer to each 10 square feet of surface. Then add 1 inch of soil and enough water to moisten but not soak it. This process is repeated until the pile is 4 to 5 feet high. Make the top of the pile concave to catch rainwater.
If alkaline compost is wanted, ground limestone can be spread in the pile at the same rate as the fertilizer.
The compost pile will not decay rapidly until the weather warms up in spring and summer. In midsummer, decay can be hastened by forking over the pile so moisture can get to parts that have remained dry. The compost should be ready for use by the end of the first summer (fig. 2).
Figure 2 - Compost ready for use in the garden.
For a continuing supply of compost, a new pile should be built every year. Compost can be used as a mulch, or worked into flower beds and the vegetable garden. (fig. 3).
Figure 3 - Using a soil-compost mixture under
and around plants in the garden.
When properly prepared and thoroughly decayed, compost is not likely to harbor diseases or insects. If the compost is used in soil where an attempt is made to control plant diseases, or if it is mixed with soil used for raising seedlings, the soil should be disinfected with chemicals recommended by your local Extension agent or State agricultural college.
Commercial fertilizers may be used to advantage in most farm gardens, the composition and rate of application depending on locality, soil, and crops to be grown. On some soils with natural high fertility only nitrogen or compost may be needed. The use of fertilizers that also contain small amounts of copper, zinc, manganese, and other minor soil elements is necessary only in districts known to be deficient in those elements. State experiment station recommendations should be followed. Leafy crops, such as spinach, cabbage, kale, and lettuce, which often require more nitrogen than other garden crops, may be stimulated by side dressings. As a rule, the tuber and root crops, including potatoes, sweetpotatoes, beets, carrots, turnips, and parsnips, need a higher percentage of potash than other vegetables.
The quantity of fertilizer to use depends on the natural fertility of the soil, the amounts of organic matter and fertilizer used in recent years, and the crops being grown. Tomatoes and beans, for example, normally require only moderate amounts of fertilizer, especially nitrogen; whereas onions, celery, lettuce, the root crops, and potatoes respond profitably to relatively large applications. In some cases, 300 pounds of commercial fertilizer may be sufficient on a half-acre garden; in other cases, as much as 1,000 to 1,200 pounds can be used to advantage.
Commercial fertilizers, as a rule, should be applied either a few days before planting or when the crops are planted. A good practice is to plow the land, spread the fertilizer from a pail or with a fertilizer distributor, then harrow the soil two or three times to get it in proper condition and at the same time mix the fertilizer with it. If the soil is left extremely rough by the plow, it should be harrowed once, lightly, before fertilizing. For row crops, like potatoes and sweetpotatoes, the fertilizer may be scattered in the rows, taking care to mix it thoroughly with the soil before the seed is dropped or, in the case of sweetpotatoes, before the ridges are thrown up.
Application of the fertilizer in furrows along each side of the row at planting time does away with the danger of injury to seeds and plants that is likely to follow direct application of the material under the row. The fertilizer should be placed so that it will lie 2 to 3 inches to one side of the seed and at about the same level as, or a little lower than, the seed.
The roots of most garden crops spread to considerable distances, reaching throughout the surface soil. Fertilizer applied to the entire area, therefore, will be reached by the plants, but not always to best advantage. Placing fertilizer too near seedlings or young plants is likely to cause burning of the roots. The fertilizer should be sown alongside the rows and cultivated into the topsoil, taking care to keep it off the leaves so far as practicable.
Heavy yields of top-quality vegetables cannot be obtained without an abundance of available plant food in the soil. However, failure to bear fruit and even injury to the plants may result from the use of too much plant nutrient, particularly chemical fertilizers, or from an unbalanced nutrient condition in the soil. Because of the small quantities of fertilizer required for short rows and small plots it is easy to apply too much fertilizer. The chemical fertilizers to be applied should always be weighed or measured. Table 1 shows how much fertilizer to apply to each 50 or 100 feet of garden row or to each 100 to 2,000 square feet of garden area.
Table 1. Approximate rates of fertilizer application
per 50 or 100 feet of garden row and per 100 to 2,000
square feet of garden area, corresponding to given rates per acre.
If it is more convenient to measure the material than to weigh it, pounds of common garden fertilizer, ammonium phosphate, or muriate of potash, may be converted roughly to pints or cups by allowing 1 pint, or 2 kitchen measuring cups, to a pound. For example, table 1 gives 0.25 pound for a 100-pound-per-acre application to 100 square feet. This would call for about 1/4 pint, or 1/2 cup, of fertilizer. Ground limestone weighs about 1 1/3 times as much as the same volume of water; therefore, measured quantities of this material should be about one-fourth less than those calculated as equivalent to the weights in the table. For example, 3/4 pint of ground limestone weighs about 1 pound. Ammonium sulfate and granular ammonium nitrate are much lighter, weighing about seven-tenths as much as the same volumes of water; therefore, volumes of these substances calculated by the foregoing method should be increased by about one-third.
Most plants develop well in soils that are slightly acid to neutral (6.0 to 7.0) provided the proper nutrients are in the soil. These nutrients are available to plants in this range of pH. Generally, soils in moist climates are acid and those in dry climates are alkaline. A soil with a pH lower than 7.0 is an acid soil and one with a pH higher is alkaline. A soil analysis will reveal the pH of the soil so that a decision can be made on whether to alter the pH or not. The county Extension agent can supply information on soil tests that can be performed for each locality. (Samples of soil should not be sent to the U.S. Department of Agriculture.)
Acid soils can be limed to bring the pH to the favorable range. Lime, ground limestone, marl, or ground oyster-shells on garden soils serves a threefold purpose: (1) To supply calcium and other plant nutrients; (2) to reduce soil acidity; (3) to improve the physical character of certain heavy soils. As a rule, asparagus, celery, beets, spinach, and carrots are benefitted by moderate applications of lime, especially on soils that are naturally deficient in calcium. Dolomitic limestone should be used on soils deficient in magnesium. Most garden vegetables do best on soils that are slightly acid and may be injured by the application of lime in excess of their requirements. For this reason lime should be applied only when tests show it to be necessary. In no case should the material be applied in larger quantities than the test indicates. Most garden soils that are in a high state of fertility do not require the addition of lime.
Alkaline soils may be treated with an acid producing material. Organic matter, sulfur, and some sulfur containing materials can be used. When using organic matter in the form of manure, care must be taken that the manure itself is not alkaline. Some manures are alkaline and contain high amounts of soluble salts which are detrimental to plants, especially when applied in alkaline soils.
With good drainage, plenty of organic matter in the soil, and the moderate use of commercial fertilizers, the growth requirements of nearly all vegetables may be fully met.
CHOOSING GARDEN TOOLS back to top
Very few tools are necessary for a small garden. It is better to buy a few simple,
The cultivating tools, or attachments, for the wheel hoe should include one or more of the so-called hoe blades. They are best for weeding and are used more than the cultivator teeth or small plow usually supplied with a wheel hoe.
For gardens over 4,000 square feet, a rotary garden tiller is useful in preparing the soil for planting and controlling weeds.
Many gardeners who do little or no farming have the choice of hiring equipment for garden-land preparation or buying their own. Equipment for hire too often is unavailable when needed, so that a favorable season for planting may be missed. Country gardeners, in increasing numbers, are turning to small farm and garden tractors for land preparation, cultivation, lawn mowing, and hauling sprayers in gardens and orchards. Those who garden every year and who have large homesteads usually find this equipment a good investment. The size and type of equipment needed depend on the amount of work to be done, the contour of the land, and the character of the soil. For cultivating and other light work a 2- to 3-horsepower tractor is used. If plowing or other heavy work is involved, a larger tractor is desirable. Modern outfits of this size are well adapted to cultivating small areas. A medium-size tractor suitable for cultivating a large garden can also be used for plowing.
The rotary tiller, which is capable of preparing light to medium soils for planting in one operation, has been widely adopted by gardeners who have such soils. In the hands of a careful operator and on land that is not too hard and heavy and is reasonably free from stones, roots, and other obstructions, this machine has many desirable features. It can be adjusted to cultivate very shallowly or to plow the soil and fit it for planting. Tools such as sweeps may be attached, thereby adapting the machine to straddle-row cultivating.
Use of well-adapted implements in preparing garden land greatly lessens the work required in cultivating. Clean, sharp, high-grade tools greatly lessen garden labor. For larger gardens, a wheel-type hand fertilizer distributor, a sprayer or duster (preferably a wheelbarrow-type power sprayer), and a seed drill are generally profitable. Minor tools include two pointed iron stakes and weeders.
If sufficient water is available, irrigation equipment is necessary in many areas and highly desirable in nearly all gardens. Furrow application requires careful planning and laying out of the garden area and precise handling of the soil to insure even distribution of water. Overhead pipes with nozzles at short intervals, temporary lines of lightweight pipe with rotating sprinklers, and porous hose laid along the rows are extensively used. The most common practice is to use a length or two of garden hose, with or without sprinklers, fed by faucets on temporary or permanent lines of pipe through the garden.
In winter, when there is little heat from the sun, little water is used by plants so irrigation is not needed in most areas. However, in summer, rainfall is usually inadequate and irrigation is essential for maximum production.
ARRANGING THE GARDEN back to top
No one plan or arrangement for a garden can suit all conditions. Each gardener must plan to meet his own problem. Careful planning will lessen the work of gardening and increase the returns from the labor. Planting seeds and plants at random always results in waste and disappointment. Suggestions for planning a garden are here presented with the idea that they can be changed to suit the individual gardener.
The first consideration is whether the garden is to be in one unit or in two. With two plots, lettuce, radishes, beets, spinach, and other vegetables requiring little space are grown in a small kitchen garden, and potatoes, sweet corn, pumpkins, melons, and other vegetables requiring more room are planted in a separate patch, as between young-orchard-tree rows or in other areas where conditions are especially suitable for their culture.
The cultivation methods to be employed are important in planning the garden. When the work is to be done mainly with a garden tractor, the site and the arrangement should be such as to give the longest practicable rows. On slopes of more than 1 1/2 percent, especially on light-textured soil, the rows should extend across the slope at right angles, or on the contours where the land is uneven. The garden should be free from paths across the rows, and turning spaces of 10 to 12 feet should be provided at the ends. The rows for small-growing crops may be closer together for hand cultivation than for cultivation with power equipment.
Any great variation in the composition of the soil within the garden should be taken into consideration when deciding on where to plant various crops. If part of the land is low and moist, such crops as celery, onions, and late cucumbers should be placed there. If part is high, warm, and dry, that is the proper spot for early crops, especially those needing a soil that warms up quickly.
Permanent crops, such as asparagus and rhubarb, should be planted where they will not interfere with the annual plowing of the garden and the cultivation of the annual crops. If a hotbed, a coldframe, or a special seedbed is provided, it should be either in one corner of, or outside, the garden.
Tall-growing crops should be planted where they will not shade or interfere with the growth of smaller crops. There seems to be little choice as to whether the rows do or do not run in a general east-and-west or in a general north-and-south direction, but they should conform to the contours of the land.
Succession of Crops
Except in dry-land areas, all garden space should be kept fully occupied throughout the growing season. In the South, this means the greater part of the year. In fact, throughout the South Atlantic and Gulf coast regions it is possible to have vegetables growing in the garden every month of the year.
In arranging the garden, all early-maturing crops may be grouped so that as soon as one crop is removed another takes its place. It is desirable, however, to follow a crop not with another of its kind, but with an unrelated crop. For example, early peas or beans can very properly be followed by late cabbage, celery, carrots, or beets; early corn or potatoes can be followed by fall turnips or spinach. It is not always necessary to wait until the early crop is entirely removed; a later one may be planted between the rows of the early crop - for example. sweet corn between potato rows. Crops subject to attack by the same diseases and insects should not follow each other.
In the extreme North, where the season is relatively short, there is very little opportunity for succession cropping. In dry-land areas, inter-cropping generally is not feasible, because of limited moisture supply. Therefore, plenty of land should be provided to accommodate the desired range and volume of garden crops.
Late Summer and Fall Garden
Although gardening is commonly considered a spring and early-summer enterprise, the late-summer and fall garden deserves attention too. Second and third plantings of crops adapted to growing late in the season not only provide a supply of fresh vegetables for the latter part of the season, but often give better products for canning, freezing, and storing. Late-grown snap and lima beans and spinach, for example, are well adapted to freezing and canning; beets, carrots, celery, and turnips, to storage. In the South, the late-autumn garden is as important as the early-autumn one.
SELECTING SEED back to top
Except in special cases, it pays the gardener to buy seed from reputable seedsmen and not to depend on home-grown supplies. Very fine varieties that do extremely well in certain areas have been grown for long periods from locally produced seed, and such practices are to be commended, provided adequate measures are taken to keep the strains pure.
Vegetables that are entirely, or readily, cross-pollinated among plants of their kind include corn, cucumbers, melons, squash, pumpkins, cress, mustard, brussels sprouts, cabbage, cauliflower, collards, kale, kohlrabi, spinach, onion, radish, beet, and turnip. Those less readily cross-pollinated are eggplant, pepper, tomato, carrot, and celery. Beans, peas, okra, and lettuce are generally self-pollinated, but occasionally cross-pollinated, lima beans sometimes rather extensively. Because sweet corn will cross with field corn, it is unwise to save sweet corn seed if field corn is growing in the same neighborhood. Hybrid sweet corn should not be saved for seed. The custom of saving seed from a choice watermelon is safe, provided no citrons or other varieties of watermelons are growing nearby. Likewise, seed from a muskmelon is safe, even though it was grown side by side with cucumbers. Beans do not readily cross and their seed also may be saved. Cabbage, kohlrabi, kale, collards, broccoli, and cauliflower all intercross freely, so each must be well isolated from the others if seed is to be saved.
Seeds should be ordered well in advance of planting time, but only after the preparation of a garden plan that shows the size of the plantings and the quantity of seed required. Table 2 shows the quantity of seed required for a given space, but allowance should be made for the possible need of replanting. Crops and varieties that are known to be adapted to the locality should be selected. The agricultural experiment station of each State, local Extension agents, and experienced gardeners are usually able to give advice about varieties of vegetables that are adapted to the area. Standard sorts of known quality and performance are usually the best choice.
Table 2 - Quantity of seed and number of plants required for 100 feet of row
depths of planting, and distances apart for rows and plants.
Disease-resistant strains and varieties of many important vegetables are now so generally available that there is little reason for risking the loss of a crop through planting susceptible sorts. This phase of the subject is treated in detail under the individual crops.
Some seeds retain their vitality longer than others. Seeds may be divided into three groups as follows: (1) Comparatively short-lived, usually not good after 1 to 2 years - corn, leek, onion, parsley, parsnip, rhubarb, and salsify; (2) moderately long-lived, often good for 3 to 5 years - asparagus, beans, brussels sprouts, cabbage, carrot, cauliflower, celery, kale, lettuce, okra, peas, pepper, radish, spinach, turnip, and watermelon; and (3) long-lived, may be good for more than 5 years - beet, cucumber, eggplant, muskmelon, and tomato.
STARTING THE PLANTS back to top
Table 2 gives in general the proper depth of planting for seed of the various vegetables, the quantity of seed or number of plants required for 100 feet of row, and the correct spacing of rows and of plants within the row. Special planting suggestions are given in the cultural hints for the various garden crops.
Earliness, economy of garden space, and lengthening of the growing season may be obtained by setting the plants of many vegetables instead of sowing the seed directly in the garden. Moreover, it is almost impossible to establish good stands from seed sown directly in place in the garden with delicate plants, such as celery, under average conditions.
In the warmer parts of the United States, practically all vegetable plants may be started in specially prepared beds in the open with little or no covering. In the temperate and colder regions, if an early garden is desired, it is essential that certain crops, such as tomatoes, peppers, eggplant, early cabbage, cauliflower, and early head lettuce, be started indoors, in hotbeds, or in coldframes. Occasionally onion, beet, cucumber, squash, and melons are started under cover and transplanted.
Starting Plants in the House
Seeds can be germinated and seedlings started in a box, pan or flowerpot of soil in a window. In addition to having at least 6 hours of direct sunlight each day, the room must be kept reasonably warm at all times.
Washed fine sand and shredded sphagnum moss are excellent media in which to start seeds. Place a layer of easily drained soil in the bottom of a flat and cover this soil with a layer - about three-fourths inch thick - of either fine sand or sphagnum moss. Press the sand or moss to form a smooth, firm seedbed.
Then, using a jig (fig. 4), make furrows in the seedbed one-half inch deep. Water the sand or moss thoroughly and allow it to drain.
Figure 4 - One-half-inch furrows made with a jig.
Sow seeds thinly in the rows and cover the seeds lightly with a second layer of sand or moss. Sprinkle the flat, preferably with a fine mist, and cover the flat with a sheet of clear plastic film (fig. 5). The plastic film diffuses and subdues the light and holds moisture in the soil and air surrounding the seeds. Plastic films offer advantages over glass coverings in that they are light in weight and are nonshattering.
Figure 5 - Clear plastic film gives a flat, even
subdued light and holds the moisture.
Place the seeded and covered flat in a location that is reasonably warm at all times and has 6 hours of direct sunlight each day. The flat will require no further attention until after the seedlings have developed their first true leaves (fig. 6). They are then ready to transplant to other containers.
Figure 6 - Seedlings with first true leaves ready for transplanting.
It is seldom possible to keep the transplanted plants in house windows without their becoming spindling and weak. For healthy growth, place them in a hotbed, coldframe, or other place where they will receive an abundance of sunshine, ample ventilation, and a suitable temperature.
Strong, vigorous seedlings can be started under 40-watt fluorescent tubes (fig. 7). These tubes should be 6 to 8 inches above the seedlings. Temperatures should be about 60F at night and 70F during the day. Best results are obtained if the fluorescent fixture is next to a window to increase the amount of light reaching the young plants.
Figure 7 - Starting plants under fluorescent light opposite a window.
Soil pellets are the simplest and easiest method for starting plants and are readily available from garden supply stores and other sources. Soil pellets are a well-balanced synthetic soil mixture and are free of soilborne diseases and weeds (fig. 8).
Figure 8 - Soil pellets, left to right, unmoistened, moistened
with emerging seedling, and lettuce
plant ready to plant in the garden.
Special Devices for Starting Plants
In determining the type of equipment for starting early plants, the gardener must consider the temperature and other climatic conditions in his locality, as well as the nature of the plants to be started. Hardy plants, such as cabbage, need only simple inexpensive facilities, but such heat-loving, tender seedlings as peppers and eggplant must have more elaborate facilities for successful production. In the warmer parts of the United States, and in the well-protected locations elsewhere, a coldframe or a sash-covered pit on the sunny side of a building usually suffices (fig. 9). In colder sections, or in exposed areas elsewhere, some form of artificial heat is essential. Where only a little protection against cold damage is needed, a coldframe in which a temporary bank of lamps can be placed may be sufficient. The hotbed, lean-to, or sash greenhouse heated by manure, pipes, flues, or electricity are all widely used, the choice depending on conditions. A comparatively small plant-growing structure will provide enough plants for several gardens, and joint efforts by a number of gardeners will usually reduce the labor of producing plants.
Figure 9 - Growing early plants in a glass coldframe
located on the south side of the house. Some heat
is applied from the basement window.
The plant-growing structure should always be on well-drained land free from danger of flooding. A sunny, southern exposure on a moderate slope, with trees, a hedge, a board fence, or other form of windbreak on the north and west, makes a desirable site. Plenty of sunshine is necessary.
Hotbeds and other plant-growing devices require close attention. They must be ventilated at frequent intervals, and the plants may require watering more than once daily. Convenience in handling the work is important. Sudden storms may necessitate closing the structure within a matter of minutes. Plant growing at home should not be undertaken by persons obliged to be away for extended periods, leaving the plant structure unattended.
A tight well-glazed structure is necessary where the climate is severe; less expensive facilities are satisfactory elsewhere.
Covers for hotbeds and coldframes may be glass sash, fiber glass, plastic film, muslin, or light canvas.
In the moderate and cooler sections of the country, standard 3- by 6-foot hotbed sash is most satisfactory. Even this requires supplementary covering with canvas, blankets, mats, or similar material during freezing weather. The amount of covering is determined by the degree of heat supplied the structure, the severity of the weather, and the kind of plants and their stage of development. Farther South, where less protection is necessary, a muslin cover may be all that is needed and for only a part of the time.
Many substitutes for glass as coverings for hotbeds and coldframes are on the market. The most widely used substitutes are various kinds of clear plastic film. Some of these have a lifespan of only one season, and others a lifespan of 3 to 5 years.
Clear plastic film transmits as much light as glass in the visible range, and more than glass in the ultraviolet and infrared ranges.
The film comes as flat sheets (on rolls) and in tubular form. Flat-sheet film is used for tacking onto wooden frames; the tubular form is used for enclosing metal tubular frames with a tight double layer of film.
Large plant hoods made from semicircular aluminum or galvanized steel pipe and fitted with a sleeve of tubular plastic film (fig. 10) make excellent coldframes or seasonal row covers. When used in this way, a double layer of plastic film provides an air space that insulates against 4 degrees to 7 degrees of frost temperature change.
Figure 10 - A double layer of plastic film supported by semicircular galvanized pipe makes a
highly satisfactory portable coldframe.
Electrically heated plant beds are ideal for the home gardener, provided electric rates are not too high. The beds may be built any size. Because they are equipped with thermostatic control, they require a minimum of attention. It is not possible to buy frames - completely equipped with heating cables, switches, and thermostats - ready to assemble and set in position. Fill the frames with soil or plant boxes and connect to a source of current (fig. 11). Small frames may be removed at the end of the season and stored; larger frames are usually treated as a permanent installation. For more detailed information, see USDA Leaflet 445, Electric Heating of Hotbeds.
Figure 11 - An electrically heated glass hotbed with
thermostatic control is ideal for the home gardener.
Plants should be gradually hardened, or toughened, for 2 weeks before planting in the open garden. This is done by slowing down their rate of growth to prepare them to withstand such conditions as chilling, drying winds, shortage of water, or high temperatures. Cabbage, lettuce, onion, and many other plants can be hardened to withstand frost; others, such as tomatoes and peppers cannot. Withholding water and lowering the temperature are the best ways to harden a plant. This may be done in a glass or plastic coldframe.
About 10 days before being planted in the open ground, the young plants in beds or flats are blocked out with a large knife. Blocking, or cutting the roots, causes new roots to form quickly near the plants, making recovery from transplanting in the open easier. Blocking also makes it easier to remove the plants from the bed or flat with minimum injury.
Vegetable plants grown outdoors in the South are shipped to all parts of the country. They are grown cheaply and usually withstand shipment and resetting very well. They may not always be as good as home-grown plants, but they save the trouble of starting them in the house or in a hot-bed. Plants of beets, brussels sprouts, cabbage, cauliflower, lettuce, onions, peppers, and tomatoes are extensively grown and shipped; tomato, cabbage, and onion plants make up the bulk of the shipments. The plants are usually wrapped in bundles of 50 each and shipped by either mail or express. Tomato and pepper plants are packed with a little damp moss around the roots, but onion and cabbage plants are usually packed with bare roots. Shipments involving large numbers of bundles are packed in ventilated hampers or slatted crates and usually are sent by motor-truck or rail express. Shipments by air mail and air express are increasing.
The disadvantages of using southern-grown plants are the occasional delays in obtaining them and the possibility of transmitting such diseases as the wilt disease of the tomato, black rot of cabbage, and disorders caused by nematodes. State-certified plants that have been carefully inspected and found as free of these troubles as can be reasonably determined are available. Southern-grown plants are now offered for sale by most northern seedsmen, by mail-order houses, and often by local hardware and supply houses.
The term "transplanting" means shifting of a plant from one soil or culture medium to another. It may refer to the shifting of small seedlings from the seedbed to other containers where the plants will have more space for growth, or it may mean the setting of plants in the garden row where they are to develop for the crop period. Contrary to general belief, transplanting does not in itself stimulate the plant or make it grow better; actually growth is temporarily checked, but the plant is usually given more space in which to grow. Every effort should be made during transplanting to interrupt the growth of the plant as little as possible.
Plants started in seed flats, flowerpots, and other containers in the house, the hotbed, the greenhouse, or elsewhere should be shifted as soon as they can be handled to boxes, flowerpots, plant bands, or other containers where they will have more room to develop. If shifted to flats or similar containers, the plants should be spaced 2 or more inches apart. This provides room for growth until the plants can be moved to their permanent place in the garden. Most gardeners prefer to place seedlings singly in flowerpots, paper cups with the bottoms pierced for drainage, plant bands, berry boxes, or other containers. When the plants are set in the garden, the containers are carefully removed.
Soil for transplanting should be fertile, usually a mixture of rich topsoil and garden compost, with a very light addition of a commercial garden fertilizer.
Moistening the seedbed before removing the seedlings and care in lifting and separating the delicate plants make it possible to shift them with little damage to the root system and with only minor checks to their growth. Plants grown singly in separate containers can be moved to the garden with almost no disturbance to the root system, especially those that are hardened for a week or two before being set outdoors. Plants being hardened should be watered sparingly, but just before they are set out, they should be given a thorough soaking.
Plants grown in the hotbed or greenhouse without being shifted from the seedbed to provide more room and those shipped from the South usually have very little soil adhering to the roots when they are set in the garden. Such plants may require special care if transplanting conditions are not ideal; otherwise, they will die or at least suffer a severe shock that will greatly retard their development. The roots of these plants should be kept covered and not allowed to dry out. Dipping the roots in a mixture of clay and water helps greatly in bridging the critical transplanting period. Planting when the soil is moist also helps. Pouring a half pint to a pint of water, or less for small plants, into the hole around the plant before it is completely filled is usually necessary. A starter solution made by mixing 1/2 pound of a 4-12-4 or 5-10-5 commercial fertilizer in 4 gallons of water may be used instead of plain water. It is usually beneficial. Finally, the freshly set plants should be shaded for a day or two with newspapers.
Plants differ greatly in the way they recover from the loss of roots and from exposure to new conditions. Small plants of tomatoes, lettuce, beets, cabbage, and related vegetables are easy to transplant. They withstand the treatment better than peppers, eggplant, and the vine crops. When started indoors and moved to the field, the vine crops should be seeded directly in berry baskets or containers of the same size that can be transferred to the garden and removed without disturbing the root systems. Beans and sweet corn can be handled in the same manner, thereby often gaining a week or two in earliness.
Book Recommendatons back to top
Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long
One of the most important elements of success in growing vegetables is planting, or transplanting, each crop at the time or times that are best for the operation in each locality. Temperatures often differ so much between localities not many miles apart that the best planting dates for some one vegetable may differ by several days or even 2 weeks.
Vegetable crops may be roughly grouped and sown according to their hardiness and their temperature requirements. A rough timetable for planting some of the commoner crops is shown in table 3, based on the frost-free dates in spring and fall. The frost-free date in spring is usually 2 to 3 weeks later than the average date of the last freeze in a locality and is approximately the date that oak trees leaf out.
Table 3. Some common vegetables grouped according
to the approximate times they can be planted and
their relative requirements for cool and warm weather.
The gardener naturally wants to make the first planting of each vegetable as early as he can without too much danger of its being damaged by cold. Many vegetables are so hardy to cold that they can be planted a month or more before the average date of the last freeze, or about 6 weeks before the frost-free date. Furthermore, most, if not all, cold-tolerant crops actually thrive better in cool weather than in hot weather and should not be planted late in the spring in the southern two-thirds of the country where summers are hot. Thus, the gardener must time his planting not only to escape cold but with certain crops also to escape heat. Some vegetables that will not thrive when planted in late spring in areas having rather hot summers may be sown in late summer, however, so that they will make most of their growth in cooler weather.
A gardener anywhere in the United States can determine his own safe planting dates for different crops by using the maps (figs. 12 and 13), together with tables 4 and 5, in this bulletin. The maps show the average dates of the last killing frosts in spring and the average dates of the first killing frosts in fall. They are the dates from which planting times can be determined, and such determinations have been so worked out in tables 4 and 5 that any gardener can use them, with only a little trouble, to find out the planting dates for his locality.
MEAN DATE OF LAST 32 DEGREE (F.) TEMPERATURE IN SPRING
Figure 12 - Average dates of the last killing frost in spring.
MEAN DATE OF FIRST 32 DEGREE (F.) TEMPERATURE IN AUTUMN
Figure 13 - Average dates of the first killing frost in fall.
Table 4, for use with the map in figure 12, shows planting dates between January 1 and June 30, covering chiefly spring and early-summer crops. It shows how early it is safe to plant; it also shows the spring and early-summer dates beyond which planting usually gives poor results.
Table 4. Earliest dates, and range of dates, for safe spring planting of vegetables in the open.
Opposite each vegetable in table 4, the first date in any column is the earliest generally safe date that the crop can be sown or transplanted by the gardener using that column. (No gardener needs to use more than one of the columns.) The second date is the latest date that is likely to prove satisfactory for the planting. All times in between these two dates may not, however, give equally good results. Most of the crops listed do better when planted not too far from the earlier date shown.
To determine the best time to plant any vegetable in the spring in your locality:
1. Find your location on the map in figure 12 and then, the solid line on the map that comes nearest to it.
2. Find the date shown on the solid line. This is the average date of the last killing frost. The first number represents the month; the second number, the day. Thus, 3-10 is March 10. Once you know the date you are through with the map.
3. Turn to table 4; find the column that has your date over it; and draw a heavy line around this entire column. It is the only date column in the table that you will need.
4. Find the dates in the column that are on a line with the name of the crop you want to plant. These dates show the period during which the crop can safely be planted. The best time is on, or soon after, the first of the two dates. A time halfway between them is very good; the second date is not so good.
For areas in the Plains region that warm up quickly in the spring and are subject to dry weather, very early planting is essential to escape head and drought. In fact, most of the cool-season crops do not thrive when spring-planted in the southern part of the Great Plains and southern Texas.
Table 5 is used with the map in figure 13 in the same way to find the dates for late plantings. The recommendations for late plantings and for those in the South for overwintered crops are less exact and less dependable than those for early planting. Factors other than direct temperature effects - summer rainfall, for example, and the severity of diseases and insects - often make success difficult, especially in the Southeast, although some other areas having the same frost dates are more favorable. A date about halfway between the two shown in table 5 will generally be best, although in most areas fair success can be expected within the entire range of dates shown.
Along the northern half of the Pacific coast, warm-weather crops should not be planted quite so late as the frost date and table would indicate. Although frost comes late, very cool weather prevails for some time before frost, retarding late growth of crops like sweet corn, lima beans, and tomatoes.
Table 5. Latest dates, and range of dates, for safe fall planting of vegetables in the open.
CARING FOR THE GARDEN back to top
In most areas the garden requires a moisture supply equivalent to about an inch of rain a week during the growing season for best plant growth. It requires roughly that amount of watering a week to maintain good production if the moisture stored in the soil becomes depleted and no rain falls over periods of weeks. An inch of rain is equivalent to about 28,000 gallons on an acre, or 900 gallons on a 30- by 50-foot garden.
It is much better to give the garden a good soaking about once a week than to water it sparingly more often. Light sprinklings at frequent intervals do little, if any, good. The best way to apply water, when the soil and slope are suitable, is to run it the length of furrows between the rows until the soil is well soaked. If the soil is very sandy or the surface too irregular for the furrow method, sprinklers or porous irrigating hose must be used.
Weeds rob cultivated plants of water, nutrients, and light. Some weeds harbor diseases, insects, and nematodes that reinfest garden crops in succeeding years.
As soon as the soil can be properly worked after each rain or irrigation, it should be thoroughly hoed or cultivated to kill weeds that have sprouted and to leave the surface in a loose, friable condition to absorb later rainfall. The primary value of hoeing or cultivating is weed control. This cultivation should be shallow so as to avoid injuring the vegetable plant roots that lie near the surface. Although it is desirable to keep the surface soil loose, there is little to be gained by hoeing or cultivating oftener than necessary to keep weeds out of the garden.
In small gardens, weeds can be controlled with black polyethylene mulch (fig. 14) supplemented by hand weeding such as pulling, hoeing, and wheel hoeing. Mulching vegetable crops with organic material also is a common practice in small gardens.
Figure 14 - Black plastic film conserves moisture,
controls weeds, warms the soil, and hastens maturity
of vegetable crops.
The best organic mulches are partially decomposed hay, straw, or grass clippings. The mulch should be applied 4 to 6 inches deep when the plants are about 6 inches tall. Cabbage, tomato, and other transplants usually are tall enough soon after they are set in the garden. Before applying mulch, hoe out all small weeds. Not only does mulch control weeds, it also conserves moisture, keeps the soil from packing, and increases the humus necessary for vigorous plant growth.
Herbicides for the Home Garden
Herbicides are generally not recommended for home gardens; however, trifluralin and DCPA are registered for use in many vegetable crops. If these are used, care must be taken to insure proper application. Soil fumigants usually kill most of the seeds or vegetative reproductive organs of weeds present. The non-selective, broad spectrum herbicide glyphosate may be used prior to planting to control many perennial weeds, and many gardeners use it with hand-held weed wipers to selectively control weeds in the garden.
Controlling Diseases, Insects, and Nematodes
Garden crops are subject to attack by a number of diseases and insects. Preventive measures are best, but if an attack occurs and the gardener is not familiar with the nematode, insect or disease and the proper treatment to protect his crop, he is advised to consult the county Extension agent.
Among the most important disease-control measures are the use of disease-free seeds and plants, and the use of disease-resistant varieties. Great progress has been made within recent years in the development of varieties that are resistant to certain diseases, insects and nematodes.