In New Jersey, traditional cover crops include small grains such as rye or wheat. Hairy vetch, clovers and other grasses and legumes are gaining popularity. However, selecting and integrating cover and green manure crops into a production system should entail evaluation of your own production system and the characteristics of the individual species. In selecting a cover crop, first identify your objective, problem or need. To increase organic matter, plant non-legumes or mixture of grasses and legumes.
Small grains can provide significant amounts of biomass vegetation.
Once tilled under, the vegetation decomposes over time, adding valuable organic matter and humus. During this process, nitrogen may become immobilized or unavailable to plants, particularly when crop residues or stalks are tilled into the soil. Combining these crops with legumes, or applying additional nitrogen fertilizer or manure, can help to reduce this problem by accelerating decomposition of the more mature crop material. To supply nitrogen to subsequent crops, select a legume. Legumes include alfalfa, clovers and hairy vetch.