White granular crystals, highly soluble in water and insoluble in organic solvents; melting point 117.3°C, strongly acidic in solution (pH 1.89 at 1%), with low thermal stability. A high-analysis nitrogen-phosphorus fertilizer (total nutrients 61%) whose acidic solution suits alkaline soils especially well; early and mid-season response is markedly better than urea, ammonium phosphate or MKP. Can be tank-mixed with water-soluble N and K fertilizers, best applied by drip irrigation or foliar spray, and is a key N and P source in compound formulations.
