Mainly used for wheat, corn, rice and other field crops, as well as fruit trees, vegetables and flowers and other crops that need long-term supply of nutrients. Compound fertilizer is a kind of fertilizer that contains nitrogen, phosphorus, potassium and other nutrient elements in proportion. It has the advantages of high nutrient content, few by-components and good physical properties, which can meet the needs of crop growth and promote the high and stable yield of crops.