It is sometimes used as a fertilizer; as such, its NPK formula is 17-44-0. It is soluble in water, and produces a strongly acidic solution. Urea phosphate is sometimes added to blends which contain calcium nitrate and magnesium nitrate to produce water-soluble formulas such as 15-5-15, 13-2-20, and 13-2-13. The acidity of urea phosphate allows Ca, Mg and P to co-exist in solution. Under less acidic conditions, there would be precipitation of Ca-Mg phosphates. Urea phosphate is often used in Drip irrigation to clean the pipe system.