Source: Magness et al. 1971
In general purple vetch resembles hairy vetch, with pubescent stems and pods. It is, however, the least winter hardy of the commonly grown vetches, and temperatures below 20 F. generally cause injury. It is grown mainly in milder sections of California where it is primarily a hay crop. Stems are up to 30 inches or more in length, prostrate or climbing. Leaves consist of 5 to 8 pairs of linear to oblong-linear leaflets. It is little grown in colder climates where spring seeding would be necessary.