Cowpea is an annual twining herb vine or nearly erect herb in Leguminosae and Cowpea. Sometimes the top is twisted. Stems subglabrous. Pinnate compound leaves; Stipules lanceolate, linear; Leaflets ovate-rhombic, apex acute, glabrous. Racemes axillary, with long peduncles; Flowers gather at the top of inflorescence, and there are often fleshy dense glands between pedicels; Calyx light green, bell-shaped, flag petal oblate, wing petal slightly triangular, keel petal slightly curved; Ovary linear and hairy. Pods droop, erect or obliquely spread, linear, slightly fleshy and swollen or solid, with many seeds; The seeds are oval or cylindrical or slightly kidney-shaped, yellow-white, dark red or other colors. Flowering and fruiting in May-August. Cowpea originated in tropical Africa and is widely planted in China. Cowpea is a dry land plant, which grows in fertile soil with deep and loose soil layer and strong fertility and water retention.