By Sharon Omahen
University of Georgia
Georgians are accustomed to unpredictable winter weather. But
landscape plants don’t understand. Many have adjusted to the
recent warm spell and will suffer when temperatures drop again.
“We know to put on a winter coat when it gets cold, take it off
when it gets warm and put it back on again when it turns cold
again,” said Marco Fonseca, a University of Georgia
horticulturist.
Landscape plants don’t have this luxury.
To late to turn back
“Once they begin to change from their winter state to their
spring state,” he said,”there’s no turning back.”
Landscape plants prepare themselves for winter temperatures. Many
grow “fuzzy insulating exterior layers” for protection, he said.
“The plants also reduce the amount of water they absorb and
create their own antifreeze condition,” he said.
When winter temperatures rise, landscape plants think spring has
arrived. The soil warms and the plants pump water into their
roots and tissues.
When this happens, outdoor plants start growing, and flowering
plants begin to produce buds, Fonseca said.
“Right now, these buds are swelling and preparing to open,” he
said.
When temperatures drop, these plants will be much more
susceptible to freeze damage because of the changes they’ve made.
Soil moisture has risen during the warm spell, too, he said. When
freezing temperatures return, the soil moisture will cause plant
roots to freeze.
Mulch and cover
So what’s a home landscaper to do?
Fonseca and other UGA horticulturists recommend adding extra
layers of mulch to insulate outdoor plants’ roots. If spring
bulbs have begun to emerge, cover them with a layer of mulch
until the freeze passes.
“It’s not an attractive solution, but you can protect your larger
flowering shrubs by covering them with cloth at night,” Fonseca
said.
Cover any landscape plants that have started producing buds, like
forsythias and azaleas, he said.
“Basically, that’s all you can do,” he said. “Once the plants
begin to push and grow, they can’t turn back when Mother Nature
changes course.”
