Fruit growers and home gardeners concerned their plants might emerge too quickly from winter dormancy after two months of unusually warm weather in Indiana do not need to worry, according to climatologists based at Purdue University.
Temperatures will slowly return to seasonal norms over the next month, which is good news for growers and gardeners, Purdue officials said this week.
“There is a lot more weather to come before we know what the fruit crop outlook will be. But as of right now things are in good shape and, in fact, a bit more chilling is needed for some fruit crops,” said Bruce Bordelon, professor of horticulture and Purdue Extension viticulture and small fruit specialist.
Bordelon advised growers to be patient, giving trees, bushes and vines more time to get their winter rest.
“The general consensus for now is to delay dormant pruning until a bit later in case there is significant weather to come,” he said.
Peter Hirst, professor of horticulture and Purdue Extension commercial fruit tree specialist, says so far temperatures have not been warm long enough to threaten the state’s fruit crop.
“We really haven’t had that much warm weather,” Hirst said. “If we were to have another week with temperatures in the 70s, that would be cause for concern. Another saving grace is that the cool down we are expecting will be moderate and gradual. And we really haven’t had any extended periods of extreme cold this winter, so fruit buds are in good condition.”
Fruit-bearing trees go dormant in winter until they register enough “chilling hours” to begin blooming once temperatures exceed 50 degrees for an extended period. The number of required chilling hours varies by species, ranging from 600 hours for grapes and most peaches to 1,200 hours for apples and blueberries. Three weeks of optimal temperatures can produce 500 chilling hours.