Pea, a leguminous plant with small, round, edible seeds. The seeds, called peas, are borne in crescent-shaped pods, which also may be edible. Several kinds of pea plants are cultivated for food. This article deals with the most important type—the garden, or green, pea and its varieties.

The garden pea plant is a slender-stemmed vine with pairs of oval leaflets, large stipules (appendages at the leaf bases), and small white or purplish flowers. The peas usually are about one-fourth of an inch (6 mm) in diameter. They may be green, grayish, or cream-colored, and wrinkled or smooth. A row of about 5 to 10 peas is found inside each pod. Typical pea pods are puffy and thin-shelled. In the sugar pea variety, however, the pods are flat and fleshy.

The plant climbs by means of spirally coiled, threadlike organs, called tendrils, that grow from the tips of the leafstalks. Typical pea vines are three to six feet (90 to 180 cm) tall, and require the support of stakes, strings, chicken wire, or twiggy brush. The dwarf pea variety, common in home gardens, grows less than two feet (60 cm) tall, and needs no support. Pea vines are excellent food for livestock. The field pea is a variety grown chiefly for forage.

Pea plants cannot withstand hot weather. For this reason the seed is planted in very early spring—usually before the last frost. The vines do well in almost any soil, and need little cultivation. The peas are ready for picking in 50 to 90 days. Peas are susceptible to the diseases root rot and powdery mildew. Chief insect enemies are the pea aphid and pea weevil.

Peas are a nutritious food, rich in carbohydrates, calcium, phosphorus, iron, potassium, and vitamins A, B1, and C. Frozen peas are slightly less nutritious than fresh peas. By volume, dried peas are slightly more nutritious than fresh peas. Split peas are dried peas that split in half when their hulls are removed.

The garden pea was first cultivated in Asia and Europe thousands of years ago. It no longer grows wild, but has been bred successfully in temperate regions throughout the world. Most of the crop in the United States is frozen, canned, or dried. Among processed vegetables, peas are equalled in commercial importance only by tomatoes, sweet corn, and beans. Peas for fresh consumption are grown mainly in home and market gardens.

The garden pea is Pisum sativum; sugar pea, P. s. macrocarpon; dwarf pea, P. s. humile; field pea, P. s. arvense. Peas belong to the pea family, Leguminosae.