Early Preparation Can Protect Plants from Frost and Freeze

Anticipation tends to be a gardener’s worst enemy. Take for example the beautiful, warm weather we’ve had in the Triangle over the last two weekends that has coaxed plants to come out of their wintering hibernation.

Optimistic as ever, gardeners all over town have been seen getting their grass into shape, cleaning out flower beds, trimming their tulips, and putting in spectacular red geraniums that herald the majesty of spring. Boy, that Mother Nature can sure pull a mean practical joke.

The forecast of frost and freezing temperatures has stopped gardeners in their tracks, scrambling to protect their budding plants and hard gardening efforts.

“Twenty-eight is the magic number,” said WRAL’s Elizabeth Gardner. “If you get down to 28º for three hours, you have damage.” Temperatures are fluid overnight, and it’s rare that it sticks at any one temperature for long periods of time.

So armed with foresight and local garden centers, Triangle gardeners have what they need to hold the line, so to speak, and stay the course to prevent excessive damage to their plants.

Tim Grissom, Property Manager/Horticulturalist for Capitol Broadcasting Company, noted that “azaleas, spireas, tulips, daffodils … spring bulbs and plants that have already begun putting out new growth are at the most risk” for frost and freezing weather damage.

Even commercial farmers have to work to stay a step ahead of Mother Nature. “Peach and strawberry crops are most likely to be affected,” Gardner said, “and they’re the most prepared.” The two main tools in a farmer’s arsenal are fans that stir the atmosphere to keep the temperature from dropping, and spraying with water to protect the buds.

Luckily it’s not written anywhere that you have to be a commercial farmer to successfully protect the plants in your garden. Just cover them—it keeps the cold air out and captures the heat radiating out of the ground.

According to Grissom, burlap is the best cover to choose since plants need air circulation, though he also likes to use Typar®, a polyester fabric made by DuPont, or any type of landscape fabric that’s available at local garden centers. As a last resort—though he doesn’t recommend it—plastic can be used even though it doesn’t have the same insulating properties.

“What you want to do is cover your plants right before the sun goes down,” said Grissom, “but make sure you take the cloth off when the sun comes up and the temperature raises above freezing. If the plant gets too warm, there would be more damage because it causes the plant to grow and bloom faster.”

It’s important to keep the cover elevated and away from new plant growth. Grissom suggests a few simple tactics, like putting sticks in the ground around the plant for the cover to rest on.

Or, for those vegetables that have already been planted, “you can make little tents out of plastic storage containers or two liter bottles with the tops cut off,” he said. Place them around the base of the veggies to help keep the frosty temperatures at bay.

One final, parting thought before you get your gardening gloves back out: don’t forget to take houseplants that have spent the last few days outside sunning on the front porch back inside.