Harsh winter results in reduced Idaho wine grape crop

CALDWELL, Idaho – This year’s Idaho grape crop harvest is expected to be down significantly as a result of a bitter cold winter in the heart of Idaho wine country.

Temperatures fell in Caldwell to as low as 18 below zero in January, and many vineyard growers said they were forced to cut most of the vines to the ground and retrain them, diminishing the production of grapes this year.

“It was only for a couple of nights but it was enough to just wipe it out,” Idaho wine grape grower Michael Williamson said of the low temperatures.

Caldwell wine maker and vineyard owner Ron Bitner said the damage is the worst he has seen in 35 years, the Capital Press Agriculture Weekly reported.

Wine grapes in northern, eastern and south-central Idaho are fine, said Moya Shatz-Dolsby, Idaho Wine Commission executive director. The damage occurred around the Caldwell area in southwestern Idaho, where the majority of Idaho’s vineyards and wineries are located.

Skyline Vineyards, the state’s largest, harvests about 0.75 square miles of wine grapes in a typical year, vineyard manager Dale Jeffers said. But low temperatures that reached at least minus-20 degrees for three straight nights took a major toll on this year’s crop, he said.

The low temperature at a nearby weather station reached minus-26.9 degrees on Jan. 7, Jeffers said.

Many growers said the only reason the roots of the vines were not also damaged is because of the record or near-record snow cover that blanketed most of the region this winter.

“The incredible snow cover acted as an insulator, so the roots didn’t get really damaged,” said Tom Elias, vineyard owner and University of Idaho research assistant. “But everything above that snow cover just got toasted.”

The bright spot is the 2016 wine grape harvest in Idaho was a bumper crop, or a crop that yielded an unusually productive harvest, Shatz-Dolsby said.

Skyline Vineyards doubled production last year and most other vineyards reported about a 50 percent increase from previous years, according to an Idaho Wheat Commission news release on Idaho’s 2016 wine grape harvest.

“The 2016 harvest was huge, and what’s in the tank is hopefully going to be able to carry a lot of people through,” Shatz-Dolsby said.