Pennington Ironite Mineral Supplement 1-0-0 is a unique concentrated formula that provides a deep green lawn without the excessive growth that some nitrogen-rich fertilizers can cause. This special blend of iron and sulfur provides greening without the growth surge. This allows you to have a deep green lawn during the hot Summer months. Apply this product in-between your regular fertilizer routine for an even deeper green lawn. | Ironite 1-0-0 Dry Lawn and Garden Fertilizer | Size 15 lbs