Temperatures, reaching down into the 20’s over the weekend, put a freeze on local berry growth.
Mother Nature played a trick on local farmers when temperatures warmed up enough to promote growth and then dipped back down enough to kill off emerging buds. Dick Byne of Byne Blueberry Farms said this is the second year in a row that his blueberry crop has suffered a major loss.
“They are burnt,” he said of the nearly 90% of his Burke County blueberry crop consisting of 306 bushes. Byne needs to check with crops located around the state to see if they suffered the same, before he will know how much he has lost.
After 42 years of growing, Byne has seen his share of issues. Typically, every growing season presents a different dilemma to tackle. The same issue does not generally arise twice. Farmers expect cold snaps this time of the year, but bud development isn’t usually as progressed as the last two years. Byne attributed the premature growth to warm temperatures in December. Last March cold temperatures killed off emerging buds too.
“This is very discouraging,” he said. “This is two years in a row.”
With no berries to pick, it changes Byne’s summer work schedule. It also causes him to turn the loss into his insurance agency again.
“I didn’t get in this business to file claims,” Byne said.” I got into it to sell blueberries and that’s my passion.”
Tim Myers of The Strawberry Patch on Hwy. 25 said his acre and a half of strawberries was blessed. Although his crop faced freezing temperatures and harsh winds over the weekend, most of his berries were spared.
“They came through pretty good,” he said of the plants. “We ran water for about 18 hours overnight and had a lot of ice but it seems to have preserved most of them. There are a few, especially on the edges, where the wind blew the water off that were damaged, but most of them survived.”
Myers explained how watering protects berries from harsh temperatures.
As water freezes, it releases heat, in an opposite process of evaporation. Evaporation cools by absorbing heat, he said. When water changes states from a liquid to a solid, it releases heat.
A British Thermal Unit (BTU) is a measurement of energy that it takes to raise or lower a gram of water one degree Celsius.
“Every degree Celsius that a gram of water is dropping, it releases one BTU,” My- ers said. “However, when it changes states, it releases 144 BTUs.”
It also takes energy to put the 144 BTUs into it in order to melt the ice.
Continually, adding water through overhead sprinklers, kept the ice at about 31 degrees Fahrenheit, even while the outside temperature dipped to 18 degrees.
“It’s called the Latent Heat of Fusion,” Myers said.
Somewhere along the line of 30 years of growing, Myers began using a formula to determine when to begin watering plants, he said. He didn’t wait until temperatures reached 32 degrees over the weekend to begin watering. He keeps his eye on dew points.
“This time we started at 37 degrees,” he said. “I turned on the sprinklers because the dew point was so low, it was down to about 10.”
Dew points are connected to relative humidity, he said. The dry system over the weekend came out of the North, aggravating the situation.
The rule of thumb, Myers said, is that he takes the dew point and subtracts it from 32, the temperature at which water freezes. Then he takes a third of the difference and adds it to 32, to determine the critical point at which he needs to turn on the sprinklers.
For example, if a dew point is 20, then he subtracts it from 32. Then he divides 12 by 3 and adds 4 to 32 to get 36. He begins watering at 36 degrees.
Speaking like a scientist, Myers proves that farming is more than just planting seeds and picking fruit.