Twenty Years of Progress in Organic Vegetable Research

By 2008, land under organic agricultural production in the U.S. had increased to 1.9 million ha, with 66,380 ha in organic vegetable crops. Great advancements in organic vegetable research and production have occurred since the inception of the National Organic Program (NOP) rules in 2002. This presentation will focus on three areas of the country: the Midwest (Iowa and Wisconsin); the South (Florida); and the West coast (California and Washington) where researchers have focused on improved vegetable performance, weed management, and soil quality enhancement. Results associated with different varietal selections, grafting technologies, compost applications, and reduced tillage systems will be presented. Various technologies have been explored to reduce tillage in organic systems, including the use of a no-till roller/crimper to terminate fall-planted cover crops prior to commercial crop planting in the spring. Weed management has ranged from fair to excellent in the organic no-till system, with rye/hairy vetch generally providing the most weed suppression. Crops with a high nitrogen demand, such as sweet corn, may suffer from N immobilization during cover crop decomposition. Irrigated no-till tomato yields have equaled those in tilled plots, but cover crop seed and management costs have led to higher costs of production in tilled systems. Carbon and nitrogen pools are enhanced under organic no-till and lysimeter data have shown decreased nitrate leaching under plots with cover crops. Overall, the irrigated organic no-till vegetable systems have demonstrated the most promise for reducing tillage in organic systems, and with soil carbon enhancement in no-till systems, potential green payments could offset any economic losses in no-till systems.