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Calcium Magnesium Phosphate钙镁磷肥

Calcium magnesium phosphate is a citrate-soluble phosphate fertilizer made by melting phosphate rock with magnesium- and silicon-bearing minerals at high temperature, quenching and grinding. The phosphorus is in citrate-soluble form: insoluble in water but soluble in weak acid, so its response is slower than that of water-soluble phosphates while its residual effect lasts longer.

Key points

The phosphorus is citrate-soluble and must be dissolved by soil acidity and root exudates, which makes the product better suited to acid soils.
Alkaline in reaction, it supplies magnesium, silicon and calcium as well, giving it dual value on magnesium-deficient acid soils.
Under GB/T 15063-2020, where calcium magnesium phosphate is the base phosphate and the product is marked as citrate-soluble phosphorus, the water-soluble phosphorus ratio is not tested or judged.
Listed among the products exempt from registration under China's fertilizer registration rules.