5 Quick Frost Fixes in the Garden

Being in Florida, cold weather doesn’t come often for me, but when it does, I must think about if I need to protect my plants, especially my recently planted vegetable garden. Many plants freeze when temperatures remain at 28°F for five hours, although seedlings freeze when temperatures reach 32-33°F.

Many cool-season crops are quite hardy to the cold. Vegetables like spinach, garlic, leeks, broccoli, kale, cabbage, radish, Brussel sprouts, and several others can withstand temperatures below 28 degrees. Semi-hardy vegetables can withstand a light frost ranging between 28-32 degrees. These include beets, carrots, lettuce, peas, cauliflower, and celery.

Frost covers over hoops are ideal, but if you are in a pinch and don’t have some (or in my case, they ran out in every store in town), there are a few quick fixes you can try.

1. Pick up Plants

If you have potted plants or seedlings in flats, you can simply move them to a protected area like inside, on a porch or under a deck or into a garage or shed.

2. Keep Air Circulating

Since cold, still air causes the most damage to plants, you can use an electric fan to keep frost from forming on the plants.

3. Cover Plants

You can protect plants by covering them with sheets, towels, tarps, blankets, or even cardboard. They will protect them from frost, but it may not protect them from a deep freeze (28°F for five hours). Other ways you can cover plants is to invert containers, baskets, or coolers. The key is to cover them before dark, so that you can trap the warmer air. Ideally, you should prop up any coverings, so it doesn’t touch the foliage and anchor them down so wind doesn’t blow them away. Make sure you remove any coverings in the morning with the temperatures rise. The heat from the sun can cook your plants under the coverings within a couple of days.

4. Use Incandescent Lights

Incandescent, not LED or fluorescent, lights generate heat and can raise the nearby air temperature enough to protect a plant from a deep freeze. The bulbs must be within 2-3 feet of the plants to work. I’ve seen this done for young fruit trees with Christmas lights. I plan on using my Christmas lights for this purpose this year since I didn’t hang them.

5. Protect Individual Plants

There is something called hot caps to protect individual plants. These are rigid plastic containers with venting holes that are placed on seedlings at planting time. The venting holes keep you from having to keep opening the covering. Since I don’t have hot caps and I have a lone seedling in another garden, I plan on creating one using a 2-liter bottle or gallon container with the bottom cut off. I will open the lid during the day and cap it at night.

You can also surround plants with jugs of water that sits out in the sun. As it freezes, it will release heat which can raise the temperature around the plant.

So there are some strategies you can use when a frost is coming. One last tip, make sure you water your plants during the day so that the roots are protected. It works similarly to surrounding the plant with water jugs.