Farming answer: what are the phosphate fertilizers?

Today, farmers call to consult: there are many kinds of phosphate fertilizer on the market, the introduction of each product dealer is different, how to choose the right phosphate fertilizer? There are three kinds of phosphate fertilizer: 1. Calcium superphosphate: the molecular formula of the main component is Ca (H2PO4) 2H2O, which contains 14-20% available phosphorus (P2O5). The color of the product is related to phosphate rock raw materials, which is generally gray or yellowish powder. The secondary component is anhydrous calcium sulfate, accounting for about 50% of the total, containing 3-5% free acid and secondary iron phosphate, aluminum and other compounds, is a kind of acidic fertilizer, has a certain degree of moisture absorption and caking. In the process of storage, there is the degradation of phosphorus, generally should not be stored for more than one and a half years. Calcium superphosphate is suitable for all kinds of soil and crops, and can be used as base fertilizer, topdressing and foliar spraying. 2. Heavy superphosphate: heavy superphosphate is made by decomposing phosphate rock with phosphoric acid. it is the phosphate fertilizer with the highest phosphorus content. The main ingredient, like calcium phosphate, contains available phosphorus (P2O5) 42-50%, contains 4-8% free acid, and contains little or no gypsum. Because its phosphorus content is about three times that of calcium superphosphate, it is known as heavy superphosphate or trimaterial superphosphate. The property of heavy superphosphate is more stable and soluble in water than calcium superphosphate. 3. Calcium magnesium phosphate fertilizer: calcium magnesium phosphate fertilizer is mainly composed of tricalcium phosphate Ca3 (PO4) 2, containing phosphorus P2O5) 14-20%, and also contains calcium oxide (about 40%), silicon oxide (about 20%) and magnesium oxide, etc., which belongs to wolfberry soluble phosphate fertilizer. The appearance of the product is gray-white, gray-green, gray-black powder. Slightly alkaline, non-hygroscopic caking, non-corrosive. Calcium magnesium phosphate fertilizer is suitable for all kinds of crops, but the effect of calcium-loving legume crops and silicon-loving cereal crops is better; the effect of application in acid soil is better than that in calcareous soil; it is suitable to be used as base fertilizer, it is better to compost with high quality organic fertilizer for 20-30 days before application. Click to get more nitrogen, phosphorus, potassium application techniques click to get more chemical fertilizer application techniques