Monoammonium phosphate (MAP) is a water-soluble compound containing about 52% phosphorus and 12% nitrogen.
When dissolved in water, the two basic components of the fertilizer separate again to release ammonium (NH4+) and phosphate (H2PO4–), both of which plants rely on for healthy, sustained growth.
The pH of a liquid solution containing MAP is moderately acidic, which reduces the potential for NH3 loss to the air.
When MAP is used as a foliar spray or added to irrigation water, it should not be mixed with calcium or magnesium fertilizers.
The Purity of Monoammonium Phosphate
MAP has good storage and handling properties. Some of the chemical impurities, such as iron and aluminum, naturally serve as a conditioner to prevent caking. Highly pure MAP may have a conditioner added or may require special handling to prevent clumping and caking.
As with all P fertilizers, appropriate management practices should be used to minimize any nutrient loss to surface or drainage water. A high purity source of MAP is used as a feed ingredient for fish and animals. The NH4 + is synthesized into protein and the H2PO4 is used in a variety of metabolic functions in animals.
Where to Buy MAP
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