Buckwheat (Fagopyrum esculentum) is a plant cultivated for its grain-like seeds, and also used as a cover crop. To distinguish it from a related species, Fagopyrum tataricum that is also cultivated as a grain in the Himalayas, and from the less commonly cultivated Fagopyrum acutatum, it is also known as Japanese buckwheat and silverhull buckwheat.Despite the name, buckwheat is not related to wheat, as it is not a grass. Instead, buckwheat is related to sorrel, knotweed, and rhubarb.