Greenway Biotech Monoammonium Phosphate (MAP) 12-61-0 dissolves readily in water and guarantees 61% available phosphate (P₂O₅) and 12% nitrogen, all ammoniacal, with no potash. Each gram per liter of water adds 266 ppm phosphorus and 120 ppm nitrogen.
Use it to raise phosphorus in garden beds that test low, weighed and worked into the soil before planting, or as the phosphorus source in hydroponic and fertigation recipes. Its nitrogen is all ammonium, so count it in your recipe. Dissolve it on its own and keep its concentrate separate from calcium concentrates such as calcium nitrate, because calcium and phosphate form precipitates. The solution is acidic (pH 4.0–5.0 at 1%), so check pH after mixing, and jar-test before injecting it into hard water.
Beds that already test high in phosphorus need no preplant phosphorus. For broadcasting on fields, the granular MAP 11-52-0 grade is made for that job. Packed in Madera, California, in 2 to 50 lb sizes.
