RAW Phosphorus 0.125 lb. Supplement any feeding program. Fully soluble. Easy to use. RAW Phosphorus is an essential element for plant growth. Phosphorus itself is required for all life and is often a limiting nutrient for crops. Its purpose cannot be fulfilled by any other element. Due to its many uses at all stages of growth, crops attempting to maintain optimum growth levels are often deficient in Phosphorus. RAW Phosphorus is a great way to supplement any feeding program.