4' x 50' x 1.0 mil. Black Plastic Mulch. For bigger, better, earlier crops! This premium quality, 1.0 mil. Black plastic mulch works best with or without our row covers, for the suppression of weed growth and soil water loss reduction. It also increases soil temperatures to improve the yield potential of your vegetable crops. Stops weeds, keeps soil warm, prevents compaction and retains moisture. Earliness and yield are increased, much hoeing and cultivation eliminated.