Vigna

A low, ground-hugging warm-season annual legume domesticated in West Africa (around present-day Mali and Nigeria) and grown across the continent as a hardy indigenous pulse (GBIF). Trifoliate leaves rise on short, creeping stems, and after the tiny flowers are pollinated their stalks bend down and push the developing pods into the soil, so the crop ripens UNDERGROUND like a peanut. The round, hard seeds are remarkably rich in both protein and carbohydrate, making bambara groundnut a near-complete food and a staple where harsher conditions defeat other beans. It is famously DROUGHT-tolerant and productive on hot, poor, sandy soils, fixing its own nitrogen, but it is a FROST-TENDER, warm-season annual that needs a long, warm season for the underground pods to fill. RHS lists it as a tender, drought-tolerant warm-season annual pulse for full sun, its pods ripening underground (RHS). Outside the tropics it is grown as a summer annual, sown after the last frost once the soil is warm.

A warm-season annual legume domesticated in sub-Saharan Africa (GBIF) and now grown throughout the warm world, cowpea is the black-eyed pea, southern pea, and cowpea of countless kitchens — a protein-rich African staple grown for both its young leaves and its seeds. The bushy or twining plants carry trifoliate leaves, pale lilac-to-white pea flowers, and long slender pods packed with seeds (often the familiar pale seed with a black eye). HONEST CLIMATE NOTE: this is a FROST-TENDER, warm-season ANNUAL for full sun. It is notably drought-tolerant and thrives in heat and poor soil, fixing its own nitrogen from the air, so it does not want rich nitrogen feeding — too much nitrogen gives you leaves instead of pods. Sow it after the last frost once the soil is warm and let it run through a long, hot summer; outside the tropics it is grown purely as a summer annual. The dried seeds are cooked like any bean and the young leaves are eaten as a cooked green. It is bee-pollinated but largely self-pollinating, so a single plant still sets a crop.