It is a climbing annual legume with weak, viny, and relatively succulent stems. Vines often are 4 to 5 feet long, but when grown alone, field pea's weak stems prevent it from growing more than 1.5 to 2 feet tall. Leaves have two leaflets and a tendril. Flowers are white, pink, or purple. The root system is relatively shallow and small, but well nodulated.
Growth is slow during winter but increases rapidly in warm spring weather.
Environmental preferences and limitations Field pea requires cool, moist growing conditions and can withstand heavy frost once established. It does not grow well in hot weather and is not suitable as a summer cover crop. Field pea prefers well-limed soils with a pH near 7.0, but is reported to tolerate soil pH as low as 4.2 and as high as 8.3. Field pea is not shade-tolerant and shows little salinity tolerance. Experiments in the Willamette Valley have shown that field pea stands were more erratic and less vigorous than other vetches and clovers tested.