A cold snap is expected to last until midweek and could challenge record low temperatures, meteorologists say.
View full sizeAlex Ponce picks apples Sept. 17 at Bechdolt's Orchards in Hellertown. A cold snap that will roll through the Lehigh Valley and northwest New Jersey this week is expected to be brief, but could challenge record low temperatures, meteorologists say.
While a late spring frost last year cost several local orchards large portions of their crops and ate into their profits, many said they do not necessarily expect to suffer a similar fate this year.
“But you still have to be prepared, because we still can lose everything in one morning,” said John Grim of Grim’s Greenhouse in Upper Macungie Township. “It depends on the temperature, duration, dew point, a lot of variables.”
What a WeatherWorks meteorologist based in Hackettstown describes as a “pretty cold Canadian air mass” will visit the region until midweek.
Sean Rowland says such an event isn't terribly rare for May -- it happens every couple of years, he said -- but this one could challenge record lows (33 tonight, 29 Tuesday night).
The Canadian air tends to drop temperatures 15 to 20 degrees below normal, he said. But it was 80 degrees Friday and could be 80 again by Thursday.
Temperature-sensitive plants should be brought inside, Rowland said.
'It is what it is'
Holly Mackey, of Mackey’s Orchard in White Township, said she does not expect major losses because most of her trees already bloomed in late April and early May. A pre-bloom freeze would have had a greater impact on the fruit.
Mackey said she expects to lose 10 to 15 percent of her crop, but even that may not be a bad outcome. She said some of the fruit has to be cleared out anyway so it doesn’t bunch too close together, reducing the size of the fruit produced.
“We don’t have any mechanisms in place to protect from the weather, so essentially it is what it is,” Mackey said. “We have no control over it. There’s nothing we can really do about it.”
Grim last year spent about $25,000 for equipment called a “frost dragon:" four 100-pound propane cylinders placed on tractors to heat the air and keep the blossoms from freezing.
But Grim said he had less cold-temperature problems to contend with this year, and used the equipment only three times so far compared to nine times last year.
Learning from the past
Some local owners say this cold weather will not affect them too adversely because of lessons learned from previous years’ cold fronts.
Rick Krouse, a manager at Piazza Farms & Greenhouses in Lopatcong Township, said many crops most susceptible to the cold have not yet been planted, including zucchini, peppers, cucumbers, beans, tomatoes and eggplant.
“We’re pretty used to getting hit, so we’ve learned over the years to wait until at least May 15th,” he said. “Once you get past this hump, you’re usually pretty safe. Knock on wood.”
Krouse said he may have to cover some crops and bring others into the greenhouses for warmth. Likewise, Grim said some plants will be covered with a specialized row cover that can protect plants from frost.
Melick’s Town Farm in Tewksbury Township has hired helicopters to fly over the orchards after nightfall, according to the Hunterdon County Democrat. They hope the wind generated by the helicopter's turbines will move warmer air from above to the ground and prevent the blossoms from freezing.
Melick's Town Farm is the largest fruit grower in central and northern New Jersey, with more than 10,000 apple trees and 5,000 peach trees. The orchards cover nearly 100 of the family's 300 acres of land.
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FIGHTING FROST
- Berries can suffer damage at the following temperatures, in degrees fahrenheit:
Strawberries: bud emergence (10), tight bud (22), open blossom (30).
Blueberries: bud swell (15-20), tight cluster (18-23), separate flowers visible (22-25), late closed blossom (25-26).
- Sprinkler irrigation works well on all small fruit crops. It works because water gives off heat when it changes from a liquid to a solid (i.e., freezes).
- Crops can be protected with row covers. Materials include perforated plastic, spunbonded polyester, and spunbonded polypropylene. They do not impede seedling emergence or subsequent growth of the crop.
Contact reporter Colin McEvoy at 610-258-7171 ex. 3631 or cmcevoy@express-times.com.
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