Soil organic C, total N, and available P increased 60%, 68%, and 225%, respectively, above the control with the application of 144 Mg ha−1 compost (dry wt.) during the 3-year study, but the low rate of compost (31 Mg ha−1) did not affect soil C or N. Compost N mineralization was not synchronous with sweet corn N assimilation, resulting in excess root zone nitrate that would have posed a leaching risk without the use of a winter rye N-scavenging cover crop.