Ammophos (monoammonium phosphate or MAP) 10:46 is a concentrated complex phosphorus-nitrogen fertilizer. It’s obtained by neutralizing orthophosphoric acid with ammonia. It mainly consists of monoammonium phosphate NH4H2PO4 and partially diammonium phosphate (NH4)2HPO4, which contains 10% N and 46% P2O5. Ammophos containing nitrogen and phosphorus in a well-assimilated form.
Ammophos is low-digestible and belongs to the group of hardly soluble phosphate fertilizers. This compound, which does not dissolve in water, is very poorly soluble in weak acids and completely dissolved only in sulfuric or nitric acid (strong acids).
As a rule, ammophos is used in those climatic zones where plants do not require a large amount of nitrogen, and have an acute need in phosphorus on the contrary. These include arid areas. This fertilizer is economically effective on different types of soils. The greatest effect is achieved by the joint use of ammophos with nitrogen-containing fertilizers, for example, ammonium nitrate. Insertion of these fertilizers can contribute to an increase in yield by as much as 20-40%. Difficult-soluble fertilizers should be applied as deep as possible into the soil, closer to the roots of crops, since they can’t penetrate with water into the lower layers independently.