For Wisconsin grape growers, 2011 could be a big year.

Warm, relatively dry summer weather created optimal conditions for the growing season, said Peter Botham, president of Botham Vineyards, near Barneveld. 

He called this year's yield "a once-in-a-lifetime harvest," which provides a sense of relief after losing nearly two-thirds of his crop to a late May freeze last year. Botham grows two varieties of grapes that are engineered to grow in colder climates, but not even the hybrid grapes stand up to frosts after budding.

"The crop volume changes dramatically from year to year here in Wisconsin," Botham said. "This year, we have good crop volume, but we also have extraordinarily ripe fruit."

The winery expects to average three to four tons of grapes for each of its 10 acres compared with two to three, typically.

Other growers are reporting similar results.

"Early on in the season there were some issues with pollination, but I've talked to some of the growers and they've said it's been a great year," said Ryan Prellwitz, president of the Wisconsin Grape Growers Association and owner of Vines & Rushes Vineyard in Ripon.

Wollersheim Winery in Prairie du Sac averaged 9,800 pounds of grapes per acre over its 27 acre vineyard for 2011 — a little under five tons per acre. That's slightly more than last year but not as much as in 2009, according to the winery.

"Philippe (Coquard), our winemaker, is predicting that it's probably one of our best seasons we've ever had in our 30 years of growing," said Jen Masterson, a spokeswoman for Wollersheim.

The state Department of Agriculture, Trade and Consumer Protection does not keep statistics on the relatively small grape-growing industry in Wisconsin.

Grape growers are not the only people happy with the bounty.

Botham Vineyards hires as many as 40 workers to help harvest its grapes every September. Many of the workers who look to the harvest each year as an additional source of income were disappointed by last year's crop.

"They had enough workers and they didn't have much to pick," said Lori Brown, of Barneveld.

Todd Bowens, of Dodgeville, works odd jobs but said nothing compares to the pleasure of harvesting grapes.

"Everything out here is an education for you. It's peace of mind," he said. "You can learn the roots of how the grapes were made, things that other people don't look at. It's the educational part of it and the relaxation of being here that keeps me coming back."