Berry farmers burn the midnight oil as a cold snap settles in over NC

Sunday morning’s snow was fleeting. If you slept in, you might have missed it entirely.

But strawberry farmers like Raleigh’s Danny Page did not sleep in. They were up all night, keeping one eye on the thermometer while doing everything they could to keep the plants warm. The freezing weather that arrived late Saturday is expected to return each night until Thursday, with a short reprieve Monday when overnight rains are expected to keep temperatures a few degrees above freezing.

“It’s going to be real tiresome by the time Thursday gets here,” said Page, who owns Page Farms, a 100-acre property near Brier Creek. About 50 percent of his business each year comes from the seven or so weeks the public flocks to three of those acres to pick fresh strawberries. He also raises beef cows, pumpkins and blackberries.

Rapid oscillation between 80-degree weather in February and snow and sub-freezing temperatures in mid-March has put the state’s berry farmers on high alert. Cold this early in the growing season wouldn’t typically be as much of a threat, but blooms are developing two to three weeks ahead of schedule due to last month’s unseasonable warmth, leaving them more vulnerable to a cold snap.

“Blueberries and other fruit crops have to have a certain amount of cold weather in the winter to leaf and flower normally in spring,” said Bill Cline, who specializes in small fruit crops at N.C. State University’s Cooperative Extension, an agricultural science hub for the state’s farmers. “Once that chill requirement is satisfied, they’ll go ahead and bloom. Blueberries and a lot of other crops had enough of that cold weather earlier in the winter, so when we had warm weather in February, they started blooming.”

That can be a good thing, Cline added, if the goal is to get your fruit to market before everyone else. Early-season fruits fetch a higher price. But that’s no consolation for farmers like Page, who rely on the public to come to them.

North Carolina produces the third-most strawberries of any state and leads the U.S. in “U-Pick” operations such as his. The state is the country’s sixth-largest blueberry producer, according to the Cooperative Extension.

“Right now we have green berries, so it’s a good chance we’ll have berries in March,” Page said. “And people don’t like to come out when it’s cold. Even when it’s just 70, 75 degrees. You have to get on up to 85, and then the people come out.”

It’s not the snow that worries farmers. In fact, to keep the crop safe in freezing cold, Page runs sprinklers throughout the night, coating the crop in ice. The friction of water hitting the buds and freezing on them produces heat, Page said, keeping the plants right at 32 degrees. And because the liquid in plant cells isn’t strictly water but rather a solution of glucose and other nutrients, Cline said, damage doesn’t occur until the buds hit 28 degrees or lower.

“That’s the danger zone, and it only takes a few minutes at those cold temperatures for the flower to freeze,” said Kether Smith, who runs a blueberry farm in Cedar Grove, a small community north of Hillsborough.

This is her third year raising blueberries, and she doesn’t yet have an irrigation system to keep the crops moist overnight. She put out a call on Facebook last week asking to borrow industrial-size fans, which she said help displace cold air that settles over the plot. Smith is expecting a week of late nights, as well.

“We now have seven fans that we can hook up to generators and run when it’s the coldest period of the night,” Smith said. “Maybe we gain half a degree, maybe a degree of protection. Some of our research has shown that if you put small fires out in the field, about eight to 12 per acre, that combined with the wind machine can offer about three degrees.”

Should Page and Smith weather the next few days, they won’t be able to let their guards down.

Page recalls an April night in 2007 when it got down to 22 degrees. If temperatures even approach that mark in the next few weeks, the state’s crop could be in trouble. The further a berry crop progresses, the harder it is to keep it safe in sub-freezing temperatures.

“It’s really about the earliest I’ve ever seen crops this far out in bloom,” Cline said. “So it’s an extremely risky year for spring freezes. If there’s a freeze even in late March with everything in full bloom, we risk losing the full crop.”

This story was originally published March 12, 2017 at 3:33 PM with the headline "Berry farmers burn the midnight oil as a cold snap settles in over NC."