Winter Green Manure Crops for Organic Vegetable Production in the Tidewater Virginia Region
Growing cover crops in rotation with cash crops is a common method of building soil quality and providing plant nutrients in organic production systems. Sustainable organic vegetable production in the Tidewater region of Virginia is challenging because soils are sandy and low in organic matter and early planting dates for vegetable crops provide little spring growth of winter green manure cover crops. The region lies outside the established range of suitability for the winter green manures recommended in Cooperative Extension publications, the SARE cover crops guide and ATTRA publications. The lack of research-based recommendations for winter green manure crops suitable for the production of certified organic vegetables is an important factor limiting the ability of local growers to share in this lucrative, local value-added market.
This producer will conduct three tests over two years on his certified organic farm. In the first year he will conduct a preliminary field test on five cover crop mixtures using three cover crops recommended by the SARE cover crops book as best for regions just north and south of his area. He will test hairy vetch, Austrian winter pea and crimson clover in mixtures with cereal rye on cucurbit crops. In the second year, he will take the three best covers and test them on early and late Irish potatoes.