What type of fertilizer is superphosphate (it is an acidic fertilizer and suitable for what crops)

What type of fertilizer is superphosphate?

Superphosphate is a commonly used phosphorus fertilizer, a water-soluble phosphate fertilizer, also called ordinary calcium, which is ordinary superphosphate . There is also a triple superphosphate, which is called heavy superphosphate, and some people call it heavy calcium.

Superphosphate is a phosphate fertilizer, but it has a lower phosphorus content and is one of the commonly used phosphate fertilizers. Superphosphate is dark gray or grayish white, in powder form, has a certain degree of corrosiveness, and is partially soluble in water.

Superphosphate fertilizer ingredients

Superphosphate contains 40-50% anhydrous calcium sulfate, 14% - 20% monocalcium phosphate, 3.5-5% phosphoric acid, and 2-4% sulfate . Therefore, superphosphate is an acidic fertilizer.

In addition, the effective utilization rate of phosphorus contained in monocalcium phosphate and phosphoric acid in superphosphate is 85-90% . At the same time, superphosphate contains sulfur and calcium, which can provide necessary nutrients for crops .

What crops are suitable for superphosphate

Superphosphate is widely used in various crops such as wheat, corn, rice, sorghum, cotton, melons, fruits and vegetables .

In terms of usage, superphosphate is an acidic fertilizer that can improve alkaline soil and is suitable for use in phosphorus-deficient land in Northeast, North China and Northwest China.

Suitable soil types mainly include : black soil, brown soil, purple soil, red soil, brown soil, yellow soil, yellow tidal soil, white soil, etc.

Fertilization type : Superphosphate can be used for base fertilizer, topdressing and foliar spraying . It plays an important role in promoting root and flower bud differentiation, increasing fruit set rate and early maturity. It is the main raw material for making compound fertilizers.

How to improve the utilization rate of superphosphate

In general, superphosphate is easily fixed by the soil . In alkaline soil, monocalcium phosphate is generally converted into dicalcium phosphate and octacalcium phosphate, and most of it finally forms stable insoluble apatite.

In acidic soil, aluminum phosphate and insoluble iron phosphate are formed, so the utilization rate of superphosphate is generally only 10-25%. If you want to improve the utilization rate, you can only start from the following aspects:

① Use superphosphate and organic fertilizer together. Add superphosphate during the composting process of farmyard manure. You can also mix organic fertilizer and superphosphate evenly and apply them to the soil, which can reduce the area where phosphorus contacts the soil, thereby improving fertilizer utilization.

② Deep application. Superphosphate should be applied deep into the soil when turning the soil. When sowing and topdressing, it is generally recommended to apply in strips or holes, and avoid broadcasting.

③ Mixing it with nitrogen fertilizer can improve the utilization rate of nitrogen fertilizer.

④ Take superphosphate extract for foliar spraying to improve fertilizer utilization rate.

⑤ Applying lime powder to acidic soil can neutralize the pH and reduce the chemical and physicochemical fixation of superphosphate.

⑥Making superphosphate into granular fertilizer can prolong the fertilizer effect.