Early summer could come at a price, UK ag meteorologist cautions

By Aimee Nielson

LEXINGTON, Ky. (March 22, 2012) – Without looking at the calendar, Kentuckians might easily be fooled into thinking it is early June; but in fact, spring has just begun. After the warmest winter on the record books in the Bluegrass state, spring has sprung very early causing some University of Kentucky Cooperative Extension specialists to gaze eerily back on a similar weather pattern in 2007.

“Temperatures soared in the second week of March with highs mostly in the 70s and some locations exceeding 80 degrees,” said Tom Priddy, UK agricultural meteorologist. “Rainfall was frequent; everything is turning green much earlier than usual. You can’t help but think back to 2007.”

During that year, spring came early and then a late Easter freeze decimated many horticultural and grain crops throughout the state. So what could growers and gardeners do to prepare for a possible late-season spring freeze?

“This pattern is all too familiar to that Easter freeze a few years ago,” said Patsy Wilson, UK viticulture specialist. “The best safeguard for grapes at this point is to hold off on final pruning as late as possible.”

Wilson said sometimes growers find it difficult to hold off because of vineyard size.

“As of right now, the grapes are still relatively dormant,” she added. “But we should start seeing green tips in the next week or two and that will make many cultivars vulnerable to freeze or frost damage in Central Kentucky.”

Chad Lee is a grain crops specialist at UK, and he believes wheat is the biggest concern right now, but that there’s really nothing growers can do about it. He said in Western and Central Kentucky, the crop has developed to the point where freeze or frost could cause damage.

“Now as for corn—I know farmers are itching to plant corn,” he said. “But in 2007, Kentucky growers had to replant 100,000 acres of corn. So, even though the temperatures are great, we need to wait to plant a bit longer.”

UK horticultural specialist John Strang reported many horticultural crops are running three to four weeks ahead of schedule with fruit crop bloom because of unseasonably warm weather.

“Temperatures of 25 to 26 now would cause serious damage to peach, plum and pear crops,” he said. “Temperatures of 24 to 25 would cause serious damage to the apple crop.  As bloom development progresses, the flowers will continue to lose hardiness.  I usually do not begin to feel like we have avoided most of our frost chances until late April, so we have a long way to go.”

Strang said commercial strawberry growers can use floating row covers to provide a few degrees of frost protection, and they may use overhead sprinkling to protect tender blooms if the predicted temperature drop is not too low and wind is minimal.

“Home strawberry growers can rake the straw back over the blooms for protection or cover the strawberries with a blanket,” he said. “Anchoring the edges of the blanket down will help retain the long wave radiation or heat radiating from the soil and prevent frost injury.  Covering with plastic provides little protection, and the practice of hosing the frost off of fruit crops early in the morning is not helpful.”

He added that fruit growers should concentrate on applying their early fungicide and insecticide sprays as the crops are moving through floral developmental stages very rapidly.

Priddy said temperatures have been averaging about 20 degrees warmer than normal across the state, with precipitation also a bit over the average. So after a winter that wasn’t and a spring that seems to be fleeting, Priddy suggested that growers stay alert and not get too comfortable in the warm days.

“There’s still plenty of time for a damaging freeze or frost,” he said. “We just want our Kentucky growers to be prepared.”