During the growing season, it is not uncommon for gardeners to find that protection from a late or early frost is necessary. While frost-protection covers can be purchased and stockpiled for such an occasion, many materials are already on hand around the house that can save plants from cold damage.
Sheets, blankets and towels can all be pulled from the linen closet and pressed into service if a frost is imminent. Simply place one side of the fabric at the end of a row or line of plants, and gently lay it down. Anchor the four corners with bricks or rocks to ensure any wind will not flip the linen back over, exposing the plants. The fabric protects the plants from direct contact with the cold air, and keeps the temperature several degrees warmer close to the ground.
Cardboard boxes can be placed over plants to contain warmer air, insulating the plant from the cold. The easiest method is to open the top of the box and place it upside down over the plant; then use a line of packing or duct tape to seal the small cracks around the bottom of the box to further protect the plant from cold air.
Place an inverted plant container -- made of wood, plastic or terra cotta -- over plants. Use a container that is deep enough to avoid bending the plant over, as this could break the stems and cause unintended damage to tender plants. Push the container gently but firmly against the soil so that cold air cannot seep underneath it toward the plant's roots. These can be easily placed over plants and removed the next morning.
Plastic Row Covers
Lay sheets of plastic over the plants to raise the air temperature between the plastic and the ground. Do this only at dusk, and remove them in the morning to prevent the plants from overheating. Row covers can be purchased at garden centers and kept on hand for frost protection; or use plastic tarps or drop cloths. However, do not use plastic grocery bags or thin plastic sheeting; these can actually freeze to the plant, creating more damage.
- Louisiana State University Ag Center: Protect Plants From Freezing Weather
- University of Florida Extension: The Right and Wrong Ways to Protect Plants From Cold
- Sunset: Protect Plants From Frost
- University of Arizona: Frost Protection in the Low Desert
- Mississippi State University Extension: Protecting Plants From Cold Temperatures
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