Used to lower soil temperatures in the field or garden, to hasten germination of cool weather fall crops, to prevent bolting and bitterness in heat-sensitive crops (such as lettuce and spinach) and to protect against wind damage and drying. UV stabilized, rot and mildew proof, this black polypropylene has a life of 5-7 years, more if stored out of the sun during periods of non-use. General field guidelines: for vegetables, such as tomatoes and peppers, use 30% shade cloth in areas with very hot summers; for lettuce, spinach and cole crops, use 47% in hot areas, 30% in northern or coastal climates. Use 63% for shade-loving plants. Shade cloth is also used over greenhouses in summer to reduce the need for expensive ventilation. Maximum shade density (80%) is often used over patios and skylights to cool people as well as plants. Great for winter pool covers. 10' minimum, 5 ft increments. Returns accepted on un-used, full 300' rolls only.