Auburn Extension Specialist Encouraged by Chill Hours Accumulation

Clint Thompson Alabama, Peaches, Top Posts

Cooler temperatures so far in 2021 should be an encouraging sign for Alabama fruit producers who need chilling hours to make a crop this year.

“I’m a little more encouraged,” said Edgar Vinson, assistant research professor and Extension specialist in the Department of Horticulture at Auburn University. “We did accumulate more and more than we originally thought by the end of December. It was still a little bit short. It could be made up in January or later this month and into February. It’s not the problem it was shaping up to be.”

Vinson said in mid-December that chill hour accumulation was a concern. He added that peach producers needed to have between 450 and 500 chill hours by the end of 2020. Vinson said last week that chill hours in Central Alabama were around 400. While he is encouraged, Vinson believes there is still more to catch up before producers don’t have to worry about chill hour accumulation.

“We’re still a little concerned. We’d like to see a little more towards the end,” Vinson said. “What we’re looking for are warming trends. We didn’t see very many of those, so that’s good. Especially those warming trends of short duration, those tend to be a little more costly when it comes to chill accumulation, like those 24-hour warming cycles.”

Peaches need chill hours to mature. The required chill hours depend on the peach variety, but most growers hope to get around 1,000 chill hours before spring.

Temperatures do not need to reach below freezing for chill accumulation to occur. Optimal chilling is at 42 degrees Fahrenheit.