1. Seed impregnation: seed impregnation can improve the germination rate of seeds, early emergence of seedlings, and enhance the ability of seedling roots. The general immersion concentration is 0.005-0.05%, the general immersion time is 5-10 hours, rice, cotton and other hard shell seeds for 24 hours.
2. Root impregnation: rice and sweet potato can be impregnation with humic acid sodium or humic acid potassium solution before transplanting, and the concentration is 0.01-0.05%. The results showed that the root was fast and the survival rate was high.
3. Spraying: the general concentration is 0.01-0.05% of the solution, 2-3 times of spraying in the flowering stage of crops, each mu of spraying amount is 50 liters of water solution, spraying time should be selected in the afternoon 2-4 when the effect is good.