Planting crown vetch is useful as a living green mulch for gardens and to stop erosion on steep slopes. The ability to fix nitrogen into the soil for gardens makes crown vetch a beneficial plant. The University of Kentucky uses crown vetch for soil retention on steep slopes. In both cases, the soil must be carefully prepared, as the seed can be expensive. Once the plant is established, it will reseed itself after maturity. Planting crown vetch is performed in the early spring or fall, when cool-season rains hasten germination.
Conduct a soil test in the growing area for the vetch. Collect several samples of soil from around the site. Mix the soil together. Allow it to dry. Take the soil sample to your local agricultural extension service for analysis.
Spread the types and amounts of fertilizer and agricultural lime over the crown vetch planting area as recommended by the soil test. Work the material into the soil using a rototiller or shovel. Special considerations will be required for steep slope applications. Consult your extension service agent for cultivation methods on steep slopes.
Mix the crown vetch seed with bacterial legume inoculate per inoculate label instructions. Follow the soil analysis for the type of inoculate to use for your seed species of crown vetch.
Broadcast the crown vetch seed over the soil at a rate of ½ lb. per 1,000 square feet.
Layer a straw mulch over the seed at a rate of 2 bales per 1,000 square feet to retain moisture and increase the germination rate of the seed.
Keep the seeds moist during germination. Since the seed is planted between mid-February through March or from mid-August to mid-September, extra irrigation may not be necessary.