The warm days in February felt like a blessing to many walking around town without a jacket, but it could come at a price.
Local agricultural experts warn that early warmth confuses plants and can lead to horrific damage if a late frost comes.
A look outside the window reveals many trees and other greenery starting to come alive after being dormant over the winter — even though freezing temperatures are still a threat for another six to seven weeks.
“The possibility of frost is certainly there,” said Joanna Radford, an agent with the N.C. Cooperative Extension. And will remain so until about April 22.
The mercury will dip low enough tonight to bring potential harm. By sunrise Saturday, the temperature could be down to 26 degrees in Mount Airy. At the higher elevation of some Carroll County, Virginia, farms — like Levering Orchard in Wards Gap — the low could be two or three degrees colder.
There can be crop damage on nights like these, Radford warned, depending on how low it gets and the conditions.
A particularly dry night might not create much frost even at low temperatures.
As a general rule, if it gets down to 28 degrees, strawberries need to be protected, she said. Farmers will run sprinklers; while that might seem counter-intuitive in sub-freezing weather, Radford said the water acts as an insulator that protects the bloom.
For some large farm operations, large wind machines can push air across the fields to minimize frost.
However, sprinklers and wind machines create quite a cost that many small farms can’t pay, noted Joseph Geller, Surry Community College.
It can cost $3,000 an acre for sprinklers, while a wind machine can run $10,000, said the viticulture instructor. Geller joined the college two and a half years ago after earning a master of science in viticulture and enology from California State University Fresno in 2012.
Last year was a perfect example of widespread crop damage from frost. After some warm days in March, there was a hard frost in early April, said Geller.
At SCC’s own vineyard next to the campus in Dobson, about half the chardonnay grapes were ruined. Some farms lost all their chardonnay crop, with the average for this area probably around 80, Geller estimated. Chardonnay vines bud earlier than some other varieties that fared better.
A lot of the peach crop and cherries in Virginia were hurt last year, and some apples, Radford added.
“It’s frustrating because we all like our fruit,” she said. “Some things we can’t do anything about, and the weather is one of them.”
Perhaps that’s not quite true.
A moderate winter can cause vines to come out of dormancy earlier than is healthy, Geller said. Pruning can also wake the vine up, so it’s better to postpone that on the varieties most at risk like chardonnay and cabernet franc. It’s best to do pruning on the more resistant vines, then move on to these vines.
He said the college is running an experiment this spring with some of the cabernet franc vines.
Some vines are being treated normally as the control group. Then some are being spritzed with soybean oil, while others are sprayed with a growth regulator. These two have been shown to delay bud break, which can protect from a late frost, he said.
Still, for many farmers, it comes down to hope and maybe some prayers.
Reach Jeff at 415-4692.