Dalen 5-Year Weed-Shield Landscape Fabric in the 5 ft. x 100 ft. size is a contractor-grade polyethylene weed barrier guaranteed to control weeds for up to 5 years — sized for full yards, long pathways, and multi-bed installations. Black polyethylene blocks light to stop weed germination while remaining permeable to water and nutrients so plants stay healthy. The bulk 500 sq. ft. roll is the most efficient size for landscaping contractors and large-scale garden projects.