It’s Freezing! Do I need to Cover my Plants?

Brrrr. It’s about to freeze…. Do I need to cover my plants?

That’s a thought in a lot of people’s minds. When the temperature starts to dip and freezing temps are in the forecast, it is time to think about protecting our gardens. In the Texoma area, we often see a night or two with freezing temperatures and then the days warm back up. If we protect our plants during these cold nights, we can continue to enjoy them growing for weeks.

There are different things you can use to cover your plants. A simple frost cloth is typically all we need in our area. Other things like blankets and plastic tarps can even be used. When using plastic, just make sure that you use garden hoops so the plastic tarp does not come into direct contact with the plants.

Each plant has a different tolerance to the cold, so it’s important to understand the differences. Even a light frost, around 32 degrees, can damage tender lettuces, herbs, and other plants that aren’t frost hardy. Other plants, like broccoli or cauliflower can handle temps to 28 degrees, while beets, leeks, and brussels sprouts can handle even colder weather.

It may seem counter intuitive but make sure to water the soil deeply the morning before the freeze is expected. This gives the plants time to absorb the moisture before the temperature drops, and it will strengthen them from cold damage. Additionally, moist soil retains more heat during the day and releases it more slowly at night. This acts as an insulator and helps to keep the roots warmer.

Before nightfall, cover your garden beds with your protective cover. Make sure to use rocks, bricks, or something heavy to secure the cover.

When to Cover

The chart below shows when to cover different herbs, leafy greens, and vegetables. For young, tender plants, you should consider covering them when frost is possible even if mature plants can tolerate colder temperatures.

Plant	When to Cover
Arugula	Below 28° F
Beets	Below 25° F
Broccoli	Below 28° F
Brussels Sprouts	Below 20° F
Butterhead Lettuce	Below 28° F
Carrots	Below 20° F
Cilantro	Below 32° F
Cauliflower	Below 28° F
Dill	Below 32° F
Garlic	Below 20° F
Kale	Below 15° F
Lettuce	Below 28° F
Onions	Below 20° F
Oregano	Below 20° F
Parsley	Below 20° F
Peas	Below 28° F
Radish	Below 28° F
Romaine Lettuce	Below 25° F
Rosemary	Below 30° F
Spinach	Below 20° F
Swiss Chard	Below 25° F
Thyme	Below 20° F

Here’s to getting the most out of your garden. Let’s get growing!