- An important erect legume, Vigna unguiculata, with pods to 15 cm which originated in Africa where it is grown for the dried seeds which can be black through to white or coloured. Now also grown in the Caribbean and the USA. It can be sprouted or, rarely, cooked in the pod when young. The leaves are sometimes eaten as a vegetable. The long bean which is common in southern China and Southeast Asia, has been bred from it.