Selected varieties from China. The vines, stems, flowers and tender pods are all purple, the mature seeds are black, the pods are tender, the meat is plump and delicious. Autumn purple bean is a variety bred in China. The vines, stems, flowers and tender pods are all purple, the mature seeds are black, the pods are tender and the meat is delicious. After cooking, the color changes from purple to emerald green, and the pod is 20 to 25 cm long, which is suitable for autumn sowing. It takes about 65 days from sowing to harvesting, and the yield per mu is 2000 ~ 3000 kg, which is suitable for planting in southwest China.