Floating row covers for frost protection
Floating row covers are lightweight spun-bond polypropylene or polyester fabrics laid directly over plants (or draped over hoops) that provide frost protection, wind shelter, and pest exclusion. They transmit 70-90% of sunlight and allow rain and air to pass through. Row covers come in different weights for different levels of protection. Lightweight (0.5 oz/sq yd, Agribon AG-19): 4 degrees F frost protection, 85% light, best for pest exclusion and light frost. Medium weight (1.0 oz/sq yd, Agribon AG-30): 6-8 degrees F frost protection, 70% light, good for fall and spring season extension. Heavy weight (1.5 oz/sq yd, Agribon AG-50): 8-10 degrees F frost protection, 50% light, best for winter growing. A 10x25-foot roll costs $15-25 and covers multiple beds for multiple seasons. Floating row covers keep covered plants 5-10 degrees F warmer than uncovered plants and protect to temperatures as low as 24-28 degrees F depending on weight. Secure edges with bricks, boards, or earth staples. Unlike plastic, row covers do not require ventilation because they breathe. Replace when they develop tears or become too thin from UV degradation (typically after 2-3 seasons).