Rock Phosphate is a naturally occurring mineral which has been ground to a fine dust. This dust is then granulated with a natural binder called lignosulfonate. This granulating process produces a consistently sized particle which is easy to apply and is completely free of dust. After application, this product will dissolve in water, returning the rock phosphate to a powder form. In addition to its binding qualities, Lignosulfonate naturally chelates the trace minerals in the rock phosphate making them available. Plants with high cation exchange root systems (legumes and grains) are found to be effective in obtaining phosphorous from soil and rock phosphate. This product is very effective used in conjunction with cover cropping programs. Gaia Green Rock Phosphate contains 27% total P205 with 3% available. The remaining amount of P205 is released over a period of about four (4) years.