How to use chemical fertilizers scientifically and reasonably?

By using fertilizers scientifically and rationally, their utilization rate can be significantly improved, planting costs can be reduced, and the pressure of fertilization can be alleviated. For example, soil testing is conducted first, then a targeted formula is selected for applying base fertilizer, and supplementary fertilization is carried out based on the growth condition of the crops. Fertilizer is buried in holes to reduce losses. The combination of chemical fertilizers and organic fertilizers can replenish soil organic matter and increase the utilization rate of chemical fertilizers. 
Soil testing and fertilization is a more precise method of fertilization. All soils that have not been fertilized with organic matter for a long time should have their soil nutrient conditions tested. Because soils lacking organic matter are more prone to losing fertilizer nutrients, resulting in nutrient deficiencies. After soil testing, using formulated compound fertilizers in a targeted manner will lead to better crop growth.

For vegetable fertilization, a thin and frequent fertilization method is preferable. During the peak period of crop nutrient demand, apply fertilizer in a timely manner and avoid excessive or close application to prevent plant burn. If nitrogen fertilizer is applied too shallowly in the soil, it is prone to volatilization. When applying fertilizer, make a hole about 10 centimeters deep, cover the fertilizer with soil after application, and keep the soil moisture at about 70% to facilitate the absorption of the fertilizer. Some water-soluble fertilizers can also be sprayed as foliar fertilizers in small amounts.

The concentration of fertilizer supplementation should not be too high. For example, the concentration of potassium dihydrogen phosphate should be controlled at around 0.2% to 0.3%, urea at around 0.5%, for vegetable crops it should be 0.2% to 0.3%, and for grass crops it should be 0.5% to 1.5%.