Cold snap threatens plants, crops after unseasonable warmth in Philadelphia region

After several days of unseasonable warmth, freezing temperatures are expected overnight across parts of the Delaware Valley — a sudden swing that could impact both backyard plants and commercial crops.

At Ramblewood Garden Center in Mount Laurel, New Jersey, owner Steve Coumbe spent the day preparing for the drop in temperatures, moving plants indoors and advising customers on how to protect what they've already planted.

"None of them are really going to die because of this," Coumbe said. "But it could really burn a little bit of the top growth."

Coumbe said the recent stretch of heat triggered rapid, early growth, leaving plants especially vulnerable.

"We just got through three or four days of high 80s, low 90s," he said. "That made an explosion of growth around here."

To protect plants that can't be brought inside, Coumbe recommends covering them with a frost tarp or even a cotton sheet. He cautioned against using plastic, which can trap too much heat once the sun rises.

"[A cotton sheet] lets the air go through it – it can still breathe, but it still keeps just enough heat inside to get through a night like this," he said.

The impact of the cold snap extends beyond home gardens.

At Cedarvale Winery in Logan Township, New Jersey, fourth-generation farmer Ed Gaventa said early warmth has also accelerated growth in his vineyards — raising concerns as temperatures drop.

"There's some tender growth right here," Gaventa said. "Any of this tender green tissue can get frozen."

Gaventa said the first buds of the season typically produce the strongest grape clusters, meaning damage now could affect the overall harvest.

"If the grape quantities are down, this is what we have to work with," he said.

Still, Gaventa remains cautiously optimistic.

"We've been through this many, many times," he said.

Coumbe echoed that sentiment.

"Sixty-four years we've been here, so this isn't our first rodeo," he said.