The appearance of calcium chemical magnesium phosphate fertilizer is gray-white, black-green or brown glassy fine powder, and its ingredients are relatively complex, mainly Ca3 (PO4) 2, in addition to P2O5, CaO, MgO, SiO2, CaMg and other ingredients . Due to different origins, product specifications vary greatly. Generally, the P2O5 content is between 14% and 20%, the CaO content is between 25% and 30%, the MgO content is between 10% and 15%, and the SiO2 content is between 25% and 25%. between 40%. It can be seen that calcium magnesium phosphate fertilizer is a multi-component fertilizer that mainly contains phosphorus, but also contains calcium, magnesium, silicon and other ingredients. Calcium magnesium phosphate fertilizer is insoluble in water, non-toxic, non-corrosive, non-hygroscopic, non-caking, and is a chemical alkaline fertilizer. It is widely suitable for various crops and acidic soils lacking phosphorus, especially for acidic red loam soils in the south where calcium and magnesium leaching is serious.
The role of calcium magnesium phosphate fertilizer:
Calcium magnesium phosphate fertilizer is a multi-element fertilizer, and the aqueous solution is alkaline It can improve acidic soil. It works well as a base fertilizer when cultivating large inhibitor seedlings, and the plants can slowly absorb the nutrients they need. General action on field plants, use according to specific instructions.
The specific usage characteristics are as follows:
(1) Most suitable for deep application of basal fertilizer. After calcium, magnesium and phosphate fertilizers are applied to the soil, the phosphorus can only be dissolved by weak acid and must go through a certain transformation process before it can be used by crops. Therefore, the fertilizer effect is slow and it is a slow-acting fertilizer. Generally, it is necessary to combine deep plowing and evenly apply fertilizer into the soil to mix it with the soil layer to facilitate the dissolution of soil acid and the absorption of it by crops.
(2) Paddy fields in the south can be used to dip seedling roots. The dosage per acre is about 10 kilograms, which does no harm to the seedlings and has a relatively good effect.
(3) Mix and compost with 10 times or more high-quality organic fertilizer for more than 1 month. The retted fertilizer can be used as base fertilizer, seed fertilizer, and can also be used to soak the roots of seedlings.
When using calcium magnesium phosphate fertilizer, you should pay attention to the following aspects:
(1) Calcium magnesium phosphate fertilizer is more effective when used in conjunction with ordinary calcium and nitrogen fertilizers, but it cannot be used with them. Mixed application.
(2) Calcium, magnesium and phosphate fertilizers usually cannot be mixed with acidic fertilizers, otherwise the effectiveness of the fertilizer will be reduced.
(3) The amount of calcium, magnesium and phosphate fertilizer should be appropriate. Generally, the amount per mu should be controlled between 15 and 25 kilograms. Excessive application of calcium, magnesium and phosphate fertilizers will not only fail to increase the fertilizer efficiency but will also lead to diminishing returns. Usually, when 35 to 40 kilograms of calcium, magnesium and phosphate fertilizer are applied per mu, it can be applied every other year.
(4) Calcium-magnesium phosphate fertilizer is most suitable for crops with strong ability to absorb wolfberry-soluble phosphorus, such as rapeseed, radish, leguminous green manure, leguminous crops and melons.
