High-biomass sorghum is a type of sorghum that can produce a large amount of bioenergy with a low carbon footprint. Also, unlike most bioenergy crops that grow throughout the whole year, sorghum is harvested in the fall, leaving room for winter crops to be planted. Planting winter crops not only brings financial revenue, but also helps reduce nitrogen leaching and greenhouse gas emitted from the soil. However, we first need to optimize agricultural practices, such as when to harvest sorghum, what cover crops to plant, and when to plant. In order to find out optimal management practices for sorghum-cover crop system, we harvested sorghum at three different dates (mid-August, mid-September, mid-October), followed by three corresponding planting dates for winter ryegrass and wheat, along with a no-cover crop treatment. We found out that sorghum biomass yield increased with delayed harvest, but ryegrass yield was highest in mid-September planting, with wheat being unaffected by planting dates. Soil greenhouse gas emissions were not affected by cover crop planting, but nitrogen leaching was reduced in cover crops planted in mid-September and mid-October. Our research provides guidelines for farmers and decision-makers trying to implement a sorghum-cover cropping system.