Vetch or Winter Tares can be sown anytime from March to October. It fixes nitrogen and can be mixed with other green manures. The plants establish quickly surpressing weeds as it quickly forms an excellent ground cover.
Nitrogen is stored in the roots which should be dug in with the rest of the plant in the Spring. Follow with nitrogen loving crops like leafy greens and members of the Brassica family. Cut down or hoe the crop down before digging in the whole plant 4-6 weeks before the ground is to be used.
Sow from March to September at approx 16g per square meter. Scatter on the surface of the soil then rake in and tramp down. Vetch is a member of the legume family so should be rotated with other members of that family.
125g will cover 20 square metres.