The tall, erect plant can grow from 2 to 5 ft. Stems are hollow and the plant is very prone to lodging. Stems vary in colour from green to red and brown at maturity. Buckwheat has a shallow tap root system, with numerous laterals extending to 3 to 4 ft. Flowers can be white or white tinged with pink.
Seeds are wide at the base and triangular to almost round in cross section.
Seed colour may be brown, grey-brown or black while size varies according to variety. The seed is comprised of a thick outer hull and an inner groat. Buckwheat has an indeterminate growth habit, so the crop does not mature uniformly. Plants will begin to blossom 5 to 6 weeks after sowing and will mature in 80 to 90 days. Buckwheat requires cross pollination to produce seed, so insect pollinators are essential for effective fertilization and seed set.