Pennington 30% UF 27% Nutri-Pel 15-25-5 Fertilizer is a professional turf fertilizer derived from ammonium phosphate, biosolids, muriate of potash and ureaform to keep your lawn green and healthy. It has been formulated with Uflexx to increase the amount of nitrogen in the soil of your lawn, which you can use any time of the year. It also contains Nutri-Pel fertilizer, which helps improve the condition of soil to hold water and nutrients better. For best results, apply when turf is actively growing. Use outdoors only or in a well ventilated area in commercial and residential lawns. Product comes in a 50 lb bag.