A new type of early-mature spring maize called Longdan 20 was created by crossing two specific maize plants. This hybrid maize has been found to have high yield, good quality, resistance to diseases, and can adapt well to different conditions. From 1996 to 2002, it consistently produced an average yield of 8500 to 9000 kilograms per hectare. To grow this maize successfully, it is recommended to plant it at a density of 50,000 plants per hectare in the right kind of early-mature spring maize area.