Nitrogen dynamics and yields of fresh bean and sweet corn with different cover crops and planting dates

Cover crops are recommended to mitigate N losses but effects on crop productivity have been variable and often negative. A better understanding of management-specific cover crop systems may lead to yield improvements. In 2011–2014, a split–split-plot factorial field experiment, with four replicates assessed the impact of cover crop (five species and no cover crop controls) and planting date (August vs. September) on crop yield and N dynamics. Fresh bean ( Phaseolus vulgaris L.) and sweet corn ( Zea mays L. var. rugosa ) were grown with 45 and 101 kg N ha −1 fertilizer, respectively, except for the no cover crop without fertilizer control (Nocc-NoN). Although there was a cover crop by planting date interaction ( P