COLUMBIA — A late-season frost advisory is in effect for Columbia and surrounding areas until 9 a.m. Tuesday. The projected low of 31 degrees may break the records, leaving plants and trees susceptible to damage.
According to Steven Sapp of Strawberry Hill Farms, gardeners who tried to get ahead of the game this season may not be enjoying that first tomato any time soon. Some plants, such as tomatoes and peppers, are less able to recover from colder weather. But other vegetables, such as cabbage, lettuce, cauliflower, and broccoli, will most likely survive the frost because they’re heartier, Sapp said.
Flowers may have a more difficult time with the frost, especially traditionally tropical flowers that have more moisture in the leaves, such as impatiens. Heartier flowers with stronger leaves and stems, such as pansies and petunias, may have a fighting chance.
Regardless of what type of plants you have, make sure to keep them cozy when the temperature drops tonight.
According to Sapp, it’s best to cover plants with cloth. A simple flannel bed sheet will do the trick, but make sure that it is lifted slightly off the plants so they have a little breathing room. Cardboard also works, Sapp said. Take a box, place it over low plants and flowers, and then open the box top during the day so the plants can soak up the sun.
Contrary to popular belief, Sapp said plastic isn’t the best option for covering plants because it doesn’t sufficiently shield them from frost. Stick with cloth and cardboard to save the seedlings.
As for trees, they are pretty much on their own during late-season frost. According to Milon George, associate professor of Forestry, Atmospheric Science and Horticulture at MU, most will recover. But, because the beginning of spring is a first stage of growth, trees may lose leaves during the frost because the they aren’t mature.
The calm winds and clear sky predicted for tonight will only worsen the situation, said Bart Piotter of E.C. Piotter & Sons Nursery. Clouds trap warmth and help insulate the plants, and wind helps rotate temperatures around the plants.
“When there is no cloud cover, the plant gives off their heat to the upper atmosphere,” Piotter said.
This frost prediction doesn’t match last year’s where the average during April 4 to 9 was between 16 to 19 degrees below normal temperatures.