Gardening is an enjoyable and rewarding pastime, but it can also be an endeavor that requires a bit of skill and a lot of luck. Even if you've been patient and waited until the warm days of spring to plant tomatoes, you may be surprised with an unexpected freeze that will put your tomato plants in jeopardy. On the flip side of the coin, an early autumn freeze can also put a sudden end to your tomato plants. Fortunately, a bit of advance know-how can save the day, as long as the temperatures don't drop below 28 degrees F. If temperatures drop below that point, it becomes very difficult to save the plants.
Irrigate the tomato plants a day before an anticipated freeze. Damp soil will retain heat better than dry soil. Water at the base of the plant, and avoid wetting the foliage.
Fill a milk jug or another plastic container with water and set it in a sunny spot during the day so it can absorb heat. Before evening, place the container near the tomato plant.
Cover the tomato plant with a coffee can, large bucket or cardboard box. Weigh the cover down so it won't blow away. If possible, use a cover large enough to cover the tomato plant and the container of warm water.
Protect tomato plants from a late summer freeze by covering the plants. Drive some stakes into the ground so the cover doesn't touch the plants. Covers can consist of an old tarp, blanket, burlap bags, sheets or newspapers. If you have leaves in your yard, rake them up against the tomato plants. Remove the cover in the mornings so the tomato plant can get sunlight and air.