By Deirdre Parker Smith
dp1@salisburypost.com
As if the wind and rain damage were not enough today, we are now under a frost advisory for tonight, as well as a lake wind advisory.
The wind advisory ends at 6 p.m., but the frost advisory is in effect from midnight to 9 a.m. Wednesday.
As the winds diminish, the chance of frost forming goes up, with advisories for the foothills and Piedmont of North Carolina, upstate South Carolina and northeast Georgia.
Darrell Blackwelder, director of the Cooperative Extension Service in Rowan County, says when the National Weather Service issues an advisory, it’s usually 3 to 4 degrees colder here.
The low is expected to be 34 for Salisbury, but outlying areas may drop below freezing, according to the National Weather Service.
“For some reason,” Blackwelder said, “Woodleaf always has a problem with frost.” A lot depends on if the wind is blowing, Blackwelder said. The wind is supposed to die down tonight.
“With no cloud cover, radiant heat is lost rapidly,” he said. “For a lot of people, a light frost is not a problem, but a killing frost, like 28 degrees or below, will hurt a fruit tree.”
Blackwelder said a light frost won’t do severe damage to fruit that’s already set.
“It also depends on how long it’s going to last. Sometimes it lasts only minutes.”
Redbuds, dogwood, azaleas should not be hurt,” Blackwelder said, “but it will hurt houseplants people have put outside.”
He said garden peas may be OK; a frost may burn the tops of Irish potatoes. Squash and tomatoes “should be covered with some kind of cloth, not plastic. That’s a good place to use sheets or quilts.” Some people have spent a lot of money for a system of water-filled “walls” to wrap around plants, but Blackwelder said it’s not very practical.
“Commercial strawberry growers are ready for something like this,” he said. “In some cases, a light frost on a fruit tree can be beneficial to thin the tree out.”
In our area, the last frost-free day is usually April 15
“Commercial growers wait until the 14th or 15th; others who plant early are set up with irrigation.”
He cautions homeowners not to try irrigation for frost protection, because it is more complicated than just spraying water on a plant.