Hairy vetch is a hardy, viny, annual or biennial legume, attaining a height of 24 inches when planted alone and higher when planted with a tall companion crop that provides structural support for climbing.
Thin, branched stems can reach more than 8 feet long. Compound leaves are made up of 8 to 24 paired, narrow leaflets. Leaves terminate with a tendril used for climbing. Despite its name, stems and leaves can be hairy or smooth. Hairy vetch has a taproot that extends 1 to 3 feet deep.
Fall-planted hairy vetch flowers in April and ripens seed in May-June.
Groups of 10 to 40 small, long, blue flowers hang from one side of a long flower stem. Spherical seeds (approximately 28,000/lb) are smaller than common vetch seeds. They develop in small pods and usually are grayish or black. Hairy vetch is hardseeded.
Environmental preferences and Limitations
Hairy vetch tolerates cold well and is more winter-hardy than common vetch. If well-established in fall, it tolerates frozen soils, remaining dormant until spring. Warm spring temperatures bring rapid growth.
Hairy vetch can be grown in soils with pH ranging from 4.9 to 8.2 but does best when pH is from 6.0 to 7.0. It can thrive in acid soils where clover and alfalfa do not grow well.
Hairy vetch does best on sandy or sandy loam soils but grows on most soil types if drainage is good. It tolerates some temporary flooding. Can withstand being flooded for long periods of time; however, stand quality and growth generally decline if there are long periods of flooding or saturated soils. Hairy vetch is somewhat shade-tolerant and more drought-resistant than the other vetches.
Hairy vetch is used as a cover crop, green manure, pasture, silage, and hay. It is capable of accumulating large amounts of dry matter and nitrogen. When planted alone as a winter cover crop in annual vegetable rotations, it can provide substantial amounts of nitrogen (N) to a following crop.
Hairy vetch offers excellent spring weed suppression and grows well in mixtures with cereal grains that can provide cool-weather weed suppression, erosion control, and fall N-scavenging.
Hairy vetch has been relay interplanted into vegetable crops successfully. However, when relay inter-planted into sweet corn, intense shade and heavy harvest residue result in very thin stands.
Hairy vetch is used as a self-seeding cover in orchards, usually as part of a mix. It also has been used in vineyards, but is more likely to climb trellises than is common vetch.
40 to 45 lbs per acre. 1 ¼ lbs per 1,000 square feet.