Controlled-release fertilizer is an advanced form of slow-release fertilizer. It mainly controls the release of nutrients through coating, wrapping, adding inhibitors and other technologies, prolongs the decomposition and release time of fertilizers, improves the utilization rate of fertilizer nutrients, and achieves the purpose of extending the effective period of fertilizers and promoting agricultural production. It is the main direction of modern fertilizer development at present, suitable for mechanized production, and can meet the needs of seed and fertilizer co-sowing.
◆ Common Types of Controlled-Release Fertilizers
Common controlled-release fertilizers can be divided into sulfur coating (fertilizer coating fertilizer), resin coating, urease inhibitors, etc., and can be divided into chemical type, mixed type and blended type according to the production process.
▶ Three Release Curves for Controlled-Release Fertilizers
1
High Release (Early Rapid Release)
The first half of the parabola — rapid release in the early stage. The film of this type of controlled-release fertilizer product is usually thin or the material performance is poor.
2
Uniform Release
Under the premise of constant temperature, the release is basically the same every day. If the temperature fluctuates, the difference is very small. The membrane of this type usually has no expansion, and the size of the micropores or pores is constant.
3
“S” Type Release Curve
The release is very slow in the early stage and faster in the later stage.
▶ Advantages and Disadvantages of Controlled-Release Fertilizers
✓ Advantages
- Can improve the utilization rate of fertilizers and reduce the amount of fertilizers.
- Can reduce the number of fertilizations and reduce the amount of labor.
- Can reduce crop diseases and improve the quality of agricultural products.
✗ Disadvantages
- Not suitable for use in arid and sandy land.
- The residual coating agent may cause secondary pollution.
Post time: Mar-27-2026