Winter camelina and pennycress are both oil seed crops and cold tolerant species that require less pest management inputs than winter rye and can serve as an alternative cover crop. Interseeding these species into a maize-soybean cropping system may offer successful establishment before freezing conditions. Winter camelina and pennycress establishment, growth, and winter survival could be improved through interseeding late in the maize and soybean reproductive stages. The goal of this study was to determine the effects of interseeding dates of winter camelina, pennycress, and winter rye.