The high heat and lack of consistent rainfall is creating possible hardships for crops in Kentucky. And that includes one of the more recent additions to the state’s agriculture industry: grapes.
There are about 120 grape growers spread out across Kentucky, mostly in the central, northern, and western regions. Patsy Wilson is the extension specialist for viticulture at the University of Kentucky—viticulture is the science, production and study of grapes. She says temperatures above 90 degrees can start to affect photosynthesis.
“But this really pertains to leaf temperature and not the ambient temperature,” she said. “So if we see water with these temperatures, we won’t have as negative affect on the grape vine.”
But warm overnight temperatures may create the biggest concern.
“The biggest thing that I think is the warmer nighttime temperatures,” she said. “This has a big impact on the acids in grapes where we don’t accumulate as many acids and so we’ll see this in the white wines. A good acidity is really important in the white wines.”
Wilson says overnight temperatures between 75 and 80 are reason for concern. She says most grape growers rely entirely on rainfall to sustain their crops.
“It’s not a common practice in Kentucky vineyards to have irrigation, but if we start seeing more drought-like conditions for longer periods of time this summer, irrigation might become necessary in Kentucky,” she said.
The harvest season runs from late July until mid-October, depending upon the type of grape.