There are at least four subspecies generally accepted:
- Vicia sativa ssp. cordata (Hoppe) Asch. & Graebn.
- Vicia sativa ssp. nigra (L.) Ehrh. – Narrow-leaved Vetch (= ssp./var. angustifolia, ssp. consobrina, ssp. cordata (Hoppe) Batt., ssp. cuneata, ssp. heterophylla, var. minor, var. nigra)
- Vicia sativa ssp. sativa (= var. linearis, ssp. notata)
- Vicia sativa ssp. segetalis (Thuill.) Arcang. (sometimes included in ssp. nigra)
When intended as fodder, the seed is sown densely, up to 250 kg/hectare. However, when grown for seed, less seed should be used; otherwise the crop will be too thick, reducing flower and seed production. When meant for seed, sowing is done early in the planting season for good returns; but, when for green food, any time between the first of April and the latter end of May is suitable. Sometimes, a full crop can be obtained even when sown as late as mid-June, though sowing so late is not recommended.
After the seed is sown and the land carefully harrowed, a light roller ought to be drawn across, to smooth the surface and permit the scythe to work without interruption. Also, the field should be watched for several days to prevent pigeons, which are remarkably fond of tares, from devouring much of the sown seed.
Horses thrive very well on Common Vetch, even better than on clover and rye grass; the same applies to fattening cattle, which feed faster on vetch than on most grasses or other edible plants. Danger often arises from livestock eating too much vetch, especially when podded; colics and other stomach disorders are apt to be produced by the excessive loads devoured.
Common Vetch has also been part of the human diet, as attested by carbonised remains found at early Neolithic sites in Syria, Turkey, Bulgaria, Hungary and Slovakia. It has also been reported from predynastic sites of ancient Egypt, and several Bronze Age sites in Turkmenia and Slovakia. However, definite evidence for later vetch cultivation is available only for Roman times.