Just Scentsational’s Sunshine Harvest 40lb box DAP Diammonium Phosphate is a highly soluble and quick dissolving in the soil to release both phosphate and ammonium for plant use. DAP provides a temporary soil alkalization of pH and conversion of nitrates and is an excellent way to stimulate the uptake of phosphorous and nitrogen…important nutrients for better and healthier plants and crops. A soil test is recommended before adding any fertilizers. NPK 18-46-0 Size: 40lb box