Degraded soil quality, which decreases agricultural productivity and increases nonpoint source pollution of surface water, may be ameliorated by employing soil organic matter enhancing management, such as practiced by compost use in organic farming.The value of compost applied at rates lower than those required to supply crop nutrient needs requires investigation because applying compost at agronomic nitrogen rates may not be economically feasible for organic vegetable producers.We conducted field research during 2000–2002 on a Luvisol to compare the nutrient and non-nutrient effects of various rates and timings of mixed poultry litter-yard waste compost with a traditional organic fertilizer (poultry litter) and inorganic fertilizer on environmental soil attributes and water quality in an organic vegetable crop rotation.