1, mutual benefit, using their own growth characteristics, mutual benefit. When the sweet potato was first planted, the corn seedlings sheltered the sweet potato seedlings from the sun. Practice has proved that the survival rate of interplanting sweet potato in corn field is much higher than that of planting sweet potato alone. After the sweet potato vine grows, it completely covers the ground and occupies the growth space of other weeds. Corn fields interplanted with sweet potatoes generally do not need weeding. In addition, sweet potato vines also have the function of maintaining soil moisture. The ground where sweet potatoes are planted is not easy to harden, because raindrops cannot fall directly to the ground. The soil is not easy to harden after being blocked by sweet potato leaves and flowing to the ground.
2, reduce labor intensity, corn heavy nitrogen fertilizer, sweet potato heavy potassium fertilizer. Fertilization time is also easy to master. Mainly farmyard manure, corn can grow a foot-high sweet potato seedling. When applying ear fertilizer to corn, sweet potato just entered the expansion stage, and then nitrogen fertilizer and potassium fertilizer were mainly applied once. After corn harvest, according to the growth of sweet potato vines, low-concentration potassium dihydrogen phosphate can be sprayed once. The fertilization time of the two crops almost coincides, and one fertilization greatly reduces the labor intensity of the two crops.
3. Make maximum use of the reasonable spatial collocation of space corn and sweet potato, which can make maximum use of space. Sweet potato vines will generally cover the ground and grow, and will not climb up, which will not affect the growth of corn. However, the thin leaves and high poles of corn leave enough space for the growth of sweet potato vines.