Midwest Vineyards Damaged by Frost
Ohio, Michigan vineyards among hardest hit after a warm March
Gene Sigel, who owns South River Vineyard winery in Ohio’s Grand River Valley, said there is some frost damage every spring. However, Sigel said that because of elevation or air drainage, some vineyards have not suffered frost damage in his 20 years of growing experience—nor in the past century, according to local lore.
Yet even some of those vineyards were damaged. “It really has been a once-in-a-century frost,” Sigel said.
Warm weather across the Midwest triggered bud break about three weeks early. As the balmy weather broke historic high temperature records it also caused buds to push, and growers watched young vines growing in what was still the height of frost season. Sigel told Wines & Vines that his area suffered from the early growth and the severity of the cold snap, which saw temperatures as low as 22°F on April 29.
The previous week, Sigel said highs were hovering around the mid-80°s. The freeze damaged 80%-90% of the area’s vineyards, and Sigel said of that the damage ranged from 20% to total loss.
A second dormancy
Sigel manages 170 acres of vines for three different wineries and also owns his own vineyard. He said some sites see frost damage every year. Those vineyards saw frosts earlier and went into “kind of a second dormancy.”
For the vineyards that normally don’t get hit by frost, the recent and severe cold turned 8- to 10-inch-long vine shoots into “shriveled spinach.”
Donniella Winchell, executive director of the Ohio Wine Producers Association, told the Associated Press that anywhere from 30% to 75% of Ohio’s grape crop was damaged during the recent freeze.
In Missouri, frosts occurred throughout the state, but damage varied. R. Andrew Allen, the extension viticulturist with the University of Missouri’s Institute for Continental Climate Viticulture and Enology, said vineyards in the western part of the state experienced little damage, but growers in the southeast saw significant losses. “We were almost a month ahead of schedule, and so we had been in to the growing season about four weeks or nearly a month when the frost came through, so everybody’s growth was out there and vulnerable,” he said.
Allen estimated that total state production would be reduced by 5%-10%. He said the season has been split between growers who are still tending their primary buds and are about a month ahead of growers who lost that growth during the cold weather.
Frost protection with KDL
Iowa may have lost about 40% of its primary winegrape production, according to Mike White, a viticulturist with Iowa State University. He said growers who waited the longest to prune experienced the least amount of damage.
A few growers had success by spraying at around one gallon per acre with the foliar fertilizer KDL. White said there’s “pretty good evidence” that the product can protect by 3°-4°F.
In Michigan, the spring frost was the cruelest to juice grape vineyards in the southwest part of the state, where possibly more than 90% of the crop was lost, said Thomas Zabadal, a professor with the Michigan State University Horticulture Department. “Winegrapes were largely untouched by freezes until the April 27 event,” Zabadal said. “Early varieties such as Chardonnay, Cabernet Franc, Lemberger, Foch, etc., were hurt in some vineyards as much as 50%. Nevertheless, the overall picture is brighter. I don’t have a firm statistic, but we may well have 80% or so of a crop at this point.”
He added that there’s a slight chance of another frost in May.
Indiana saw a few frosts throughout April. Bruce Bordelon, a professor and extension specialist with Purdue University, said in an email that the state is just now seeing new growth from a freeze in mid-April. “It appears that even in areas that were hard hit, the later budding varieties will have a decent crop even though there was quite a bit of damage,” he said. “We had pruned light and left many buds. It appears we have enough primary shoots for a good crop.…Earlier budding varieties that were more developed look much worse. It appears the damage was more than just to primary shoots. I see little development of secondary buds on those varieties.”
He said there was less than 50% shoot damage in the main growing area in the southern part of the state, and with careful management growers should gather close to a full crop. “We are lucky in some areas and pretty devastated in others. The wineries are already asking about other regions and if there will be a source of fruit this year.”