Phosphorus (P) and nitrogen (N) are common elements found in monoammonium phosphate (MAP). It contains the highest amount of phosphorus of any common solid fertilizer. In order to make monoammonium phosphate, 1 mole of phosphoric acid is reacted with 1 mole of ammonia, and the resulting slurry is solidified into a granular form. It can be applied during sowing (planting) as an excellent starter fertilizer.