Shandong Reascend Machinery Co.,Ltd

How to choose NPK compound fertilizer

Send Time:2023-2-12

According to fertilizer nutrient
A　　ccording to the national standard, the effective nutrient content of compound fertilizer (compound fertilizer) should be ≥40% of total nitrogen, phosphorus and potassium in high concentration and ≥25% in low concentration, excluding trace elements and medium elements; Water soluble phosphorus content ≥40%, water molecule content less than 5%; Particle size of 1 ~ 4.75 mm, etc. So in addition to looking at the brand and nutrient content, we should also pay attention to the manufacturer and origin. In addition, there are two kinds of potassium in compound fertilizer, one is potassium chloride, the other is potassium sulfate. Potassium chloride contains chlorine and should not be applied to crops that avoid chlorine. Where there is no "S" symbol on the compound fertilizer bag, the potassium is potassium chloride, avoid chlorine crops such as grapes, potatoes, tobacco, beet and so on must not be applied, must choose the fertilizer bag marked with "S" symbol of compound fertilizer, that is, composed of potassium sulfate compound fertilizer.
According to crop variety
　　NPK compound fertilizer should be used for general field crops, and wheat high-yield fields. Wheat, rice, millet and other densely planted crops, suitable for powdered compound fertilizer; Grain compound fertilizer should be used for rare cropping crops such as maize; Vegetables, especially fruit vegetables and root vegetables and fruit trees and other cash crops need more, should choose nitrogen, phosphorus and potassium fertilizer with higher potassium content, low nitrogen.
According to soil character
　　For slightly alkaline soil with low organic matter content (soil ph value is generally about 8.0) and lack of available nitrogen and phosphorus, acid compound fertilizer, such as mono-ammonium phosphate or humic acid nitrogen, phosphorus and potassium compound fertilizer, nitrogen and phosphorus compound fertilizer is appropriate. But for a few red clay or acid brown loam should choose alkaline compound fertilizer, such as diammonium phosphate, etc.
According to fertilization method
　　　In order to improve the efficiency of compound fertilizer, different dosage forms of compound fertilizer should be selected in different application methods. Granular compound fertilizer must be selected for base fertilizer application, and the higher the hardness of particles, the better, the longest fertilizer effect. It is beneficial to improve the utilization rate of nitrogen by selecting the compound fertilizer composed of ammonium nitrogen. For topdressing application, powdered compound fertilizer should be used, and it should be noted that the content of water-soluble phosphorus in the phosphorus of compound fertilizer should be more than 40%, and the nitrogen composed of ammonium nitrogen and nitrate nitrogen is suitable. The effect of base application of humic acid compound fertilizer is better than that of topdressing.