For added protection when you protect plants in a freeze, you can place plastic over the sheets or blankets to help keep warmth in. Never cover a plant with just plastic, however, as the plastic will damage the plant. Make sure that a cloth barrier is between the plastic and the plant.Click to see full answer. Regarding this, what do you cover plants with to protect from frost?Bed sheets, drop cloths, blankets and plastic sheets make suitable covers for vulnerable plants. Use stakes to keep material, especially plastic, from touching foliage. Remove the coverings when temperatures rise the next day. For a short cold period, low plantings can be covered with mulch, such as straw or leaf mold. how do I protect my garden from frost? Insulate. Spread a fresh 2- to 4-inch blanket of mulch to protect plants. Wrap. Keep plants protected with a row or plant cover, or garden blanket. Take cover. Don’t leave your plants hanging. Resist watering. Water thoroughly several days ahead of expected frost or freeze, snow or ice, if possible. Go greenhouse. In this regard, can I cover plants with garbage bags? Never use plastic of any kind, including black plastic garbage bags, to cover plants, as plastic conducts cold to the leaves and will increase the likelihood of damage to the plant. Old sheets, blankets, drop cloths and special frost protection blankets (called Reemay cloth or floating row covers) work best.At what temperature should you cover plants?If temperatures below 32 degrees F are predicted, protect your plants! A moderate freeze with temperatures in the 25- to 28-degree Fahrenheit range can be widely destructive to vegetation. Frost protection is especially important for tender plants such as geraniums, begonias, impatiens, peppers, and tomatoes.