Midwest grape growers note rising temperatures

cabernet francTed Wichmann still remembers the brutal Super Bowl of 1984, but not for the pounding the Raiders gave the hapless Redskins.

Instead, what Wichmann recalls is the wicked deep freeze that destroyed dozens of grapevines that he and his business partners had planted high on a hill near the tiny town of Alto Pass, Ill.

All it took was one bitter cold snap, in January 1984, to kill every Chardonnay and Riesling vine, roots and all.

“In one day, they were all gone,” Wichmann says.

So for the next couple decades, Alto Vineyards and every other southern Illinois grower avoided the better-known but cold-sensitive Vitis vinifera grapes, and stuck with more durable, cold-hardy French-American hybrids and native varieties.

Now all that’s changing.

Grape varietals that once fared poorly in the region are being planted in increasing numbers because of generally warmer weather.

Rising temperatures mean milder winters that no longer pose as big a threat to vinifera, which generally can’t withstand temperatures below 10 degrees Fahrenheit.

“In the last seven years, we’ve never gone below zero and last year we went to zero like one day,” Wichmann says. “Except for that day I don’t think we’ve been below 10 above.”

Actually, government weather statistics show a couple of near- and below-zero days in the region, especially in the past two winters, but there’s no disputing the trend.

Dr. Jim Angel, state climatologist at the Illinois State Water Survey, stops short of attributing the temperature shift to global warming.

chardonnay“Winters in Illinois warmed from 1895 to the 1930s, cooled off a little into the early 1970s, plunged downward in the late 1970s, and started warming up since then,” Angel says. “However, they are just now reaching the levels we saw in the period from the 1920s to the 1950s. So it’s hard to know if this is a global warming trend or just a recovery from the cold 1970s.”

(There is no dispute, however, that rising levels of greenhouse gasses will heat up the earth in time. In Illinois, average temperatures will be up from 2 to 12 degrees Fahrenheit by the year 2100, according to a study by Angel’s office.)

They may not know the cause, but growers don’t need a climatologist to tell which way the temperature gauge is moving.

“We can grow some vinifera that we didn’t think, 20 years ago, would survive,” says Paul Renzaglia, who owns Alto Vineyards, the biggest winery on the Shawnee Hills Wine Trail.

Wichmann, now a consultant to Blue Sky Vineyard near Makanda, says area growers have enjoyed success with Cabernet Franc, Chardonnay, and Cabernet Sauvignon grapes. Other varietals, such as Viornier, a white grape from France’s Rhône region, are also being tried, he says.

Karen Hand, winemaker at Blue Sky, says the Cab Franc is one of the “trickier” grapes to grow, but it’s obviously proven a success, having picked up gold at a number of prestigious wine competitions.

Warmer weather also seems to have helped long-established hybrids such as the Chambourcin and Norton, Wichmann says.

Longer growing seasons mean riper fruit with more sugar — and that translates into more alcohol, making for a full-bodied wine.

“I’d say, if anything, it’s a plus,” Wichmann says. — Roland Klose (rwklose@sbcglobal.net)