What are the types of compound fertilizers?

There are two production processes for compound fertilizers: A kind of physical mixing method is called compound fertilizer. ； The other type is minerals containing nitrogen, phosphorus and potassium, which are formed after chemical reactions and are called compound fertilizers.

At present, the compound fertilizers appearing on the market can be divided into 10 major categories. 1． Inorganic compound fertilizer. That is, inorganic chemical fertilizers are fertilizers containing nitrogen, phosphorus, potassium or two of the nutrients made by physical or chemical methods. 2. Organic-inorganic compound fertilizer. That is, a product made by adding a large amount of organic matter such as cake fertilizer, bone meal, animal excrement, peat, etc. to inorganic compound fertilizer. 3． Compound fertilizer containing trace elements. At present, many manufacturers' packages indicate that they contain boron, zinc and other trace elements. 4． Containing rare earth compound fertilizer. Refers to compound fertilizers containing certain rare earth elements, such as rare earth ammonium bicarbonate. 5. Spray application of compound fertilizer. It is divided into two categories: powder and liquid, containing a certain amount of nitrogen, phosphorus, potassium and trace elements. It has higher requirements for water solubility and less than 5% insoluble matter. 6. Liquid compound fertilizer. Such products are available in Europe and the United States * * More often, root fertilization is done primarily with a liquid fertilizer applicator or irrigation system. 7. Compound fertilizer containing microorganisms. Mainly refers to the addition of various strains of bacteria to organic-inorganic compound fertilizers. 8. Compound fertilizers containing pesticides. Refers to compound fertilizers containing a certain amount of pesticides, mainly herbicide pesticides. 9. Compound fertilizer containing humic acid. Humic acid has a certain stimulating effect on plant root growth, but because it is relatively expensive, there are not many manufacturers that add humic acid to compound fertilizers. 10. Other compound fertilizers. For example, magnetic fertilizer mainly refers to compound fertilizer that is magnetized through a special magnetization device, and the total nutrient content is greatly reduced. Its fertilizer effect is currently difficult to determine. The following points should be grasped when applying compound fertilizers: First, it is suitable for use as base fertilizer. The critical period for crops to absorb phosphorus and potassium is generally in the early stage. However, the mobility of phosphorus and potassium in the soil is small, so compound fertilizer is better as a base fertilizer. The second is to look at soil application. Different compound fertilizers should be applied according to the nutrient deficiencies of the soil and the fertilizer needs of different crops. The third is to master different application methods. The clay soil has a poor aggregate structure, but has good water and fertilizer retention properties and is not easy to leak. It should be applied deeply. ； However, sandy soil has poor water and fertilizer retention properties, so it should be applied shallowly. Ammonia nitrogen compound fertilizer is easily volatile and should be covered after application. Compound fertilizers containing phosphorus and potassium should be applied in holes near the roots of crops because phosphorus is easily fixed by the soil to facilitate absorption by the crops.

Compound fertilizers can be divided into the following categories: 1: Inorganic fertilizer, organic fertilizer, rare earth fertilizer