Cucurbit Crops Cucumbers, Gourds, Melons, Pumpkins, Squash Have Uniform Needs

by Thomas W. Whitaker.

Thomas W. Whitaker is a Plant Geneticist (Collaborator) with the Agricultural Research Service, La Jolla, Calif.

Cucurbit crops should be staples for home gardeners from Maine to California. Cucumbers, gourds, muskmelons, pumpkins, squash, and watermelons will perform satisfactorily over a wide range of climate and soil conditions. The vine, or more properly, the cucurbit crops are extremely uniform in their environmental and cultural requirements. Thus, a set of procedures designed for the culture of cucumbers can be used equally well for raising squash, with perhaps some slight modification.

The wide adaptation of the cucurbit crops to culture in temperate zone areas is surprising because they are basically tropical or semi-tropical plants, annuals, extremely frost tender, and mostly incapable of functioning normally at temperatures below 60 F. For best seed germination, temperatures of 60 to 75 are required, and for maximum seasonal growth, average mean temperatures of 65 to 85 are needed.

Considering their tropical origins, the cucurbits should thrive during the long, hot, humid days and warm nights of summer in the north temperate zone and they do. Under such circumstances, and with adequate soil moisture from rainfall or irrigation, the vines grow rapidly and respond by quickly producing fruit. Summer squash and pickling cucumbers will produce an edible product within 48 to 56 days from planting. Muskmelons require 130 to 140 days from planting. Some baking squash, pumpkins and gourds have best quality if the harvest is delayed until after the vines are senescent or have been killed by frost.

The cucurbit crops are a homogenous group, easily identified by their prostrate, sprawling vines, usually with tendrils. Each runner bears many large, lobed more or less palmate leaves (having the shape of a palm leaf). Except for the bottle gourd, the flowers are usually bright yellow, large and conspicuous. The bottle gourd has white flowers which open at night. They are pollinated by noctural insects.

Each vine bears two kinds of flowers; the large or pistillate (no anthers, female), and the smaller or staminate (no pistils, male). Commercial varieties of muskmelons have a variation on the basic pattern. In this group, perfect flowers (with both pistillate and staminate parts) are on the same plant with staminate flowers.

The botanical name for the fruit of a cucurbit is a pepo. A pepo is a fleshy, indehiscent (closed at maturity), berry-like structure, the product of an inferior ovary. Some of the fruits of cucurbits are among the largest in the plant kingdom. Squashes weighing 350 pounds have been reliably reported, and fruits of the bottle gourd are nearly as large.

The most obvious disadvantages of cucurbit crops from the viewpoint of the home gardener are their light and space requirements. They need maximum sunshine for best development. A few vigorous plants of pumpkin, watermelon or gourd can overwhelm the small garden. These disadvantages can be successfully overcome by careful site selection within the garden, by planting bush or dwarf varieties of squash, and by judicious use of a trellis, or using structures adjacent to the garden---such as fences, garages, doghouses, etc. as a substitute for a trellis.

Top, pumpkins and winter squash banana, acorn, Hubbard, and butternut. Bottom, easy does it! A little effort is worth the pies these pumpkins will make.

Nutrients. Cucurbits are not consumed primarily for their nutritional value. They contain only a sprinkling of vitamins, minerals and protein, and except for baking squashes are low in calories. Since they are low in caloric content, they are frequently used in reducing diets.

The attraction of cucurbit fruits as food is mostly to the palate. Their aroma, flavor, texture, and juiciness are among the most attractive and delightful in the vegetable world. Muskmelons make a superb breakfast fruit or dessert; besides they are relatively high in vitamins A and C. The cool, crisp, juicy, refreshing taste of a watermelon on a warm summer day is an unforgettable experience. Cucumbers, fresh or pickled, are zesty ingredients of salads and sandwiches. Summer squash, boiled and seasoned, is an extremely tasty dish, and baked squash is comparable to sweet potatoes as a dietary staple. The dessert qualities of pumpkin pie are well-known.

Cucurbits are raised mostly for their fruits which are consumed in the immature stage (summer squash, pickles), or mature stage (muskmelons, watermelons, winter squash). Gourds are allowed to mature, and then can be used as ornamentals, planters, liquid containers, work baskets, rattles, drums, etc. As food, the cucurbits can be boiled, baked, stewed, dried, pickled, or eaten uncooked. In Latin America, the staminate flowers of squash are dipped in a batter, fried, and served as a fritter. Watermelon rinds are delicious Pickled or candied.

There are reasons for thinking that squashes and pumpkins were originally domesticated for their tasty, nutritious seeds, rather than the fruit flesh. In Mexico, squash seeds, fried in oil and salted, are sold by street vendors, much like peanuts are sold at baseball games in this country. Also, in Mexico, squashes have been selected for the number and quality of their seeds as food, while the flesh is ignored.

Soils. The cucurbits are not exacting in their soil requirements. They accept almost any good garden soil, well-drained, aerated, and enriched with a generous supply of plant compost or animal manures. Sandy loams which warm up quickly in the spring are preferred for an early maturing crop, but crops can be grown on heavier soils if they are properly managed. Heavier soils have greater water-holding capacity, hence they withstand droughty conditions much better than lighter soils.

One factor that places a definite limit on the culture of cucurbit crops is soil pH. They are uniformly sensitive to acidic soils, and they require a neutral (pH 7) or even better soil with a slightly alkaline reaction. For acidic soils, treatment with lime prior to planting is mandatory.