Frost can damage many plants in your yard and garden. Sudden frost is especially hard on young, new plants, but it can also kill older, established plants as well. Keep track of frost warnings in your area even after the supposed danger of frost has passed as the weather can change in a very short period of time. Old bed sheets can be used on very large plants, but burlap fabric is one of the best protections for most plants because it breathes well and is thick.
Listen to the weather news and keep up on current weather trends. Frost conditions can happen at almost any time in the fall, winter or spring in most areas of the country.
Cover the ground around sensitive plants with a thick layer of straw or mulch to help hold in heat. Also, keep your plants watered. As strange as it may seem, ground water helps the soil to release heat during the night.
Have burlap and/or bed sheets available to cover at least the most delicate and/or expensive plants in your yard or garden. Newspaper can be used, but avoid plastic if possible, as plastic tends to hold moisture in and can do more damage than good during extreme cold snaps.
Cover your plants in the afternoon to hold in as much of the day's heat as possible. Let coverings drape all the way to the ground to form a "tent" that will prevent ground heat from escaping.
Do not wrap the trunks of trees. Allow cloth to drape all the way to the ground as wide as the drip line of the tree.
Place a 100-watt light bulb under the covering, at ground level, if possible. A light bulb gives off a considerable amount of heat and can protect even extremely frost-sensitive plants if placed under a covering, low to the ground so the heat will rise up and fill the covering. Do not allow the bulb to touch the material covering the plants (whether it is plastic or cloth) and keep the bulb and all wiring away from any water that may be on the ground in order to avoid a possible electrical shock.
Remove coverings during the day if temperatures warm to 50 degrees F or higher.