It has long been recognized by the majority of farmers that compound fertilizer can increase production and income than simple chemical fertilizer. However, how to choose high-quality compound fertilizer to achieve the purpose of saving capital and increasing production has not been mastered by the majority of farmers. Therefore, how to buy high-quality compound fertilizer according to soil characteristics, fertilizer characteristics and current agricultural production situation is what the majority of farmers need to understand and master.
1、 Scientific selection of compound fertilizer according to soil properties
For the soil with slightly alkaline, low organic matter content (soil pH value is generally about 8.0) and lack of available nitrogen and phosphorus, acidic compound fertilizer, such as monoammonium phosphate or humic acid nitrogen phosphorus potassium compound fertilizer and nitrogen phosphorus compound fertilizer, should be selected. However, alkaline compound fertilizer, such as diammonium phosphate, should be selected for a few red clay or acid brown soil.
2、 Scientific selection of compound fertilizer according to crop varieties
Nitrogen, phosphorus and potassium compound fertilizer should be selected for general field crops, and nitrogen, phosphorus and potassium ternary compound fertilizer should be selected for high-yield wheat fields; Wheat, rice, millet and other closely planted crops are suitable for powdered compound fertilizer; Granular compound fertilizer should be selected for thinly planted crops such as corn; Vegetables, especially fruits and vegetables, root vegetables, fruit trees and other economic crops need more, so nitrogen, phosphorus and potassium compound fertilizer with high potassium and low nitrogen should be selected.
3、 Select compound fertilizer scientifically according to fertilizer properties
At present, a considerable part of compound fertilizers sold on the market do not meet the national standard gb15063-94. According to the national standard, the effective nutrient content of compound fertilizer (compound fertilizer) is: the total content of high concentration nitrogen, phosphorus and potassium is ≥ 40%, and the content of low concentration nitrogen, phosphorus and potassium is ≥ 25%, excluding trace elements and medium elements; Water soluble phosphorus content ≥ 40%, water molecular content less than 5%; The particle size is 1-4.75mm, etc. Therefore, when purchasing compound fertilizer, in addition to the trademark and nutrient content, we also need to pay attention to the manufacturer and place of origin. In addition, there are two kinds of potassium in compound fertilizer, one is potassium chloride and the other is potassium sulfate. Potassium chloride contains chlorine, which is not suitable for chlorine avoiding crops. If the compound fertilizer bag is not marked with "s", its potassium is potassium chloride. Chlorine avoiding crops such as grapes, potatoes, tobacco and sugar beet must not be applied. The compound fertilizer marked with "s" on the fertilizer bag must be selected, that is, the compound fertilizer composed of potassium sulfate.
4、 Scientific selection of compound fertilizer according to fertilization method
In order to improve the fertilizer efficiency of compound fertilizer, different dosage forms of compound fertilizer should be selected for different application methods. Granular compound fertilizer must be used as base fertilizer, and the higher the hardness of the particles, the better. For example, liuguodiammonium has the highest hardness and the longest fertilizer effect. Moreover, the selection of compound fertilizer made of ammonium nitrogen in compound fertilizer is beneficial to improve the utilization rate of nitrogen. For topdressing application, powdered compound fertilizer should be selected, and it should be noted that the content of water-soluble phosphorus in compound fertilizer phosphorus should be greater than 40%, and the compound fertilizer composed of NH4-N and NO3-N is appropriate. Generally, the effect of basic application of humic acid compound fertilizer is better than that of topdressing.
