Preen Garden Grass & Weed Preventer Granules, 31.3 lb. are designed to help gardeners keep their flower beds, shrubs, and all bedding areas from unwanted weeds. These granules work by preventing weed seeds from germinating when spread and watered in, providing protection for up to three months. To achieve results, all existing weeds and grasses should be removed before application. Conveniently packaged in a ready-to-use 31.3 lb. pour bottle, this product can cover up to 5,000 square feet, making it an efficient solution for maintaining a beautiful, weed- garden. Model Number: