Calphos™ is a natural, untreated soft phosphate with colloidal clay containing valuable minor minerals in addition to phosphorus. Use at 5 lb/100 sq.ft. or 1 ton/acre on phosphate deficient soils, less on fertile soils. Supplies P and Ca for up to 5 years after application, depending on the crop.It is not acid forming, will not cake or harden and spreads easily through any type of lime, phosphate or fertilizer spreader. It is also called colloidal phosphate. The best natural source of phosphorus and calcium. It is comprised of the bony structures of prehistoric marine creatures mined in Florida from the best deposit in the country. Not the same as the hard rock phosphate, sold by most nurseries and farm suppliers, which is not nutritionally as readily available. Both an immediately available and a long-term source of phosphorus. Available only in 50 lb bags (FOB Texas). Averages 20% P2O5 (3% immediately available), 20% Ca. Calphos™ is not a complete fertilizer and should never be used as such. It is an excellent source of phosphate that is being used profitably for farmers who are interested in getting a dollar’s value for a dollar spent. When applied to the soil Calphos™ adheres to and becomes a part of the soil. It will not leach and it will not revert and once applied remains in the soil until used by the plants. Calphos™ contains no harmful acids and encourages growth of soil bacteria and earthworms. Apply Calphos™ any time, an average application rate is usually 1 Ton per acre. Available only in 50 lb bags (FOB Texas). Averages 20% P2O5 (3% immediately available), 20% Ca. Supplies P and Ca for up to 5 years after application, depending on the crop. Trees and perennials, use 1-10 lb per planting hole, depending on plant size. FOB TEXAS contact for shipping and quantity pricing.