Down to Earth OMRI Garden Gypsum - 5 lb. - improves the physical condition of landscape, lawn and garden soils while adding calcium and sulfur. Commonly used to reduce soil compaction and increase drainage in heavy clay soils, gypsum is also used to help remediate and revitalize alkaline, sodic or saline soils. OMRI listed for organic gardening.
Ingredients: Calcium Sulfate.