Vegetables

Victor R, Boswell.

All vegetable crops listed here (except watercress and taro) require soils that are well drained and are either naturally very fertile or well fertilized, regardless of the other soil characteristics that may be required or tolerated.

The soils also must have high moisture-holding capacity unless irrigation is available or rains are frequent and adequate.

These two requirements will not be repeated in the paragraphs that follow, but the requirements must be kept in mind.

It is not practicable here to list specific recommendations for applying manures and other organic matter, commercial fertilizer, and soil amendments for the several crops as grown on numerous different soils. Those subjects are treated in other chapters. Local sources of information also should be consulted.

Most vegetable crops on most mineral soils respond well to additions of organic matter and commercial fertilizers containing nitrogen, phosphorus, and potassium in the ratio of approximately 1-1.5-1 to 1-2-1, with judicious topdressings of readily available nitrogen during the early and middle stages of growth.

Leafy crops and corn typically use a high proportion of nitrogen. Fruit-, seed-, root-, and tuber-vegetables use a moderate proportion of nitrogen.

All crops on muck soils require less nitrogen and more potassium than on most mineral soils.

Only a few exceptions to these general requirements will be noted in the paragraphs that deal with individual vegetable crops.

If a soil is more acid than the optimum pH range given for individual crops in the following paragraphs, the soil should be limed to bring its acidity within the range indicated. Crops generally will tolerate a somewhat higher pH on the soils of the West that have naturally high pH values than they will on soils in the East with naturally low pH values that have been raised to high values by liming.

Artichoke, globe (Cynara scolymus), a deep-rooted perennial, does well on almost any deep, well-drained soil except one that is very sandy, droughty, or highly calcareous. A high content of organic matter in the soil and relatively cool temperatures are favorable. The plant is well adapted to a cool, moist climate, but the top is injured by freezing.

Artichoke, Jerusalem (Helianthus tuberosus) has an optimum pH of 6.5 to 7.5. Only well-drained soils of medium texture (sandy loams and loams) are recommended for this plant. Yields are low on sandy soils, plants blow over badly on sandy and muck soils, and tubers are unreasonably difficult to harvest thoroughly from fine-textured soils that tend to become hard.

Asparagus (Asparagus officinalis) is a perennial, cool-weather plant that tolerates high salt and boron content of soil. Asparagus requires an annual rest period preferably imposed by cold, and is unproductive in the southern third of the United States. Deep (3 to 4 feet or more), friable soil is necessary for extensive root penetration. Sandy loam, muck, or silty muck soils are best. Learns and silt loams are productive and widely used but tend to warm up later than sandy loams. Heavy clay loams and clays are unsatisfactory because they are cold in the spring, are hard to manage, and are conducive to the production of crooked spears. Sandy soils and subsoils tend to be droughty and sandy surface soils are subject to blowing, thereby damaging the young spears. The optimum pH is 6.0 to 7.0 on soils in the East and up to 8.0 on soils in the West.

Beans, blackeye: See peas, southern.

Beans, common (Phaseolus vulgaris): The optimum pH is about 5.8 to 6.5 on soils in the East; on western soils it is 6.0 to 7-5. Both garden and field types of common beans are very sensitive to high salt and boron content of the soil. The bean plant is a relatively shallow-rooted, warm-weather annual. The soil need not be more than 1 to 2 feet deep if an adequate water and nutrient supply can be assured. Crops of high value, such as snap beans for early market, are profitably grown on light sandy loams and even on sandy soils when they are well fertilized. Rich loams, silt loams, and clay loams are best for main-crop snap beans for market or processing and for field beans to be harvested dry. Friability, good tilth, and freedom from baking and crusting are important in obtaining good stands in the field. Inoculation with nitrogen-fixing bacteria is rarely profitable. Applications of nitrogen should be moderate.

Beans, lima (Phaseolus lunatus): Optimum soil conditions are generally similar to those required by common beans. Lima beans are moderately tolerant of salts and relatively high boron in the soil; they are less sensitive than common beans. Good drainage, warmth of soil, good tilth, and freedom from compaction or crusting are especially important in obtaining normal seedling emergence.

Beets, garden or table (Beta vulgaris): The optimum pH is 6.0 to 7.5 in eastern soils and up to 8.5 in western soils. The beet, a cool-weather plant, is the most tolerant of garden vegetables to high salt and boron content of the soil. It has a high boron requirement; often it needs added boron to prevent internal black spot of the edible roots. It is highly intolerant of high soil acidity. The soil should be very deep (4 feet or more) and well drained. Sandy loams, friable loams, and mucks are preferred. Soils that become crusted or hard interfere with seedling emergence and often cause the edible roots to become misshapen.

Broccoli, sprouting (Brassica oleracea var. botrytis): (See cabbage.) Sprouting broccoli is somewhat more sensitive to heat than is cabbage.

Brussels sprouts (Brassica oleracea var. gemmifera): (See cabbage.) This vegetable is very sensitive to high temperature. The most and firmest "heads" develop in a cool coastal climate. It is generally grown for autumn harvest.

Cabbage (Brassica oleracea var. capitata): The optimum pH is 6.0 to 7.0 in the East and up to 7.5 in the West. High pH helps control club root, a serious soilborne disease in many districts. Cabbage is moderately tolerant to high salt content and tolerant to high boron content of the soil. This cool-weather plant grows well in almost any well-drained soil of moderate (2 feet) depth or more, provided ample water is available Sandy soils require heavy applications of organic matter and fertilizer. Timely transplanting and cultivating may be difficult on heavy silt loam, clay loam, or the clay soils. Once established and properly fertilized, however, cabbage grows well on such soils. Sandy loams are best for early crops; loams and heavier soils are satisfactory for midseason and late crops of cabbage. Muck soils of high lime content are very satisfactory. Cantaloups: See muskmelons.

Carrots (Daucus carota): The optimum pH is 5.5 to 7.0. Carrots have little tolerance to high salt content, but are moderately tolerant to high boron in the soil. They require a very deep, well-drained soil, preferably a sandy loam or muck. Carrots are grown extensively on loams and silt loams, but it is usually difficult to establish good stands of plants on such fine-textured soils, which tend to form a crust, unless crust formation can be avoided. Careful control of soil moisture by furrow irrigation permits use of heavier soils than is feasible in districts of heavy rainfall. Clay soils and rocky soils impair root shape and harvest from clay soils is difficult. Coarse, undecomposed organic matter in the surface soil also tends to impair root shape.

Celeriac (Apium graveolens var. rapaceum): Optimum requirements for this "root crop" are similar to those of celery but are less exacting. It can be grown with fair success in any good garden soil.

Celery (Apium graveolens): The optimum pH is 5.8 to 7.0. Celery is intolerant of high salt content of the soil. So-called high lime mucks (pH 6.0 to 7.0) are ideal for this cool-weather crop. Very acid mucks (below pH 5.5) and alkaline mucks (above pH 7.0) are not desirable unless pH can be economically corrected.

Celery is shallow rooted and may thrive on soils only 1.5 to 2 feet deep above the water table or above hardpan. The plant has a heavy demand for water and nutrients and tolerates neither drought nor poor drainage of the surface 1.5 to 2 feet. Although mucks are ideal, celery is grown extensively on loamy sands, sandy loams and loams, and to some extent even on silt loams and clay loams provided the latter are friable and well supplied with moisture. Establishment of transplants is more difficult in coarse and fine-textured soils than in muck and medium-textured soils. Fine-textured soils are to be avoided unless soil moisture can be effectively controlled by irrigation.

Chayote (Sechium edule): (See Cucurbits.) This long-season, hot-weather vine crop produces single-seeded, pear-shaped or round fruits that weigh one-half pound or more. Fruit quality is similar to that of squash.

Chinese cabbage (Brassica pekinensis and B. chinensis): (See cabbage.) Chinese cabbage is more sensitive to high temperature than is cabbage. It forms poor heads and tends to bolt in hot weather. In most parts of the country it is best grown for autumn harvest or for winter harvest in winter-vegetable districts.

Collards (Brassica oleracea var. viridis): (See cabbage.) The optimum pH is 6.0 to 7.5. Collards are hardy. Generally they are grown for autumn harvest or, in the milder parts, for winter and early spring harvest.

Corn, sweet (Zea mays): (See corn).

Cucumbers (Cucumis sativus): (See Cucurbits.)

Cucurbits: (Cucumbers, muskmelons, watermelons, squash, pumpkins, gourds, and chayote.) Soil requirements of all are similar, but those of muskmelons and watermelons are somewhat more exacting than those of the others. (See muskmelon and watermelon.)

A generally satisfactory pH is 5.5 to 7.0 on soils in the East and up to 7.5 on soils in the West. This group of plants is generally sensitive to high salt content of the soil and moderately sensitive to high boron content. Typically shallow-rooted, the Cucurbits require as little as 1.5 to 2 feet of good soil above rock, hardpan, or other poor substrate if ample water can be provided, but deeper soils are better.

Cucurbits are grown most extensively on loamy sands, sandy loams, and loams, but cucumbers, squashes, and pumpkins for midseason or late crops are productive on friable silt loams and clay loams. Crops for early market are grown on the lighter soils, which warm up and can be worked earlier than heavy soils. Additions of organic matter to mineral soils are beneficial. Muck soils are not suitable because they tend to produce excessive vine growth at the expense of fruit and tend to be too cool.