Cool weather is bad news on grape vine

Cool weather is bad news on grape vine

The calendar may indicate it's time to pick Southern Oregon's wine grapes, but late budding triggered by a cold spring has delayed — and likely reduced — the harvest.

"The spring was not all that desirable, and I'm told this is the coolest summer we've had in 20 years," said Rob Wallace, who grows 15 grape varieties on 205 acres at Del Rio Vineyards outside Gold Hill. "Based on the spring our crop is going to be 30 percent lighter. You can count clusters all day long, but until you get it into the barn, you don't know."

Southern Oregon harvests, on average, will lag behind last year by 10 to 14 days, said Phil Van Buskirk of Oregon State University's Southern Oregon Research and Extension Center. "We're better off than most. Parts of Douglas County and farther north, I understand, are three to four weeks behind and there are concerns whether they can get the grapes ripe."

He said a longer growing season in California spurs growth of 7 to 9 tons per acre, while Southern Oregon crops max out at 4 tons per acre.

In 2009, grape growers in Jackson and Josephine counties picked 4,935 tons of grapes, or about 2.8 tons per acre, Van Buskirk said.

"You want around 3 tons per acre, on average," Van Buskirk said. "If you're thinning to get maturity, we'd be looking for even less."

As the weeks pass, nights turn colder and the pressure to start the harvest increases.

"An early fall will put all of them in jeopardy," Van Buskirk said. "It brings rain and rot. If we get an early frost, we'll lose leaves necessary to finish maturing the crop. There are ways to get around that, but you can only mature so much crop."

Wallace said Southern Oregon isn't alone in its outlook.

"From Napa all the way to Washington, it's the same," Wallace said.

A key for many vintners this year was thinning enough fruit during the primary growing season. "You've got to make sure vines have enough horsepower to get there at the end," said John Quinones of RoxyAnn Winery. "For people who haven't adjusted crops early on, it's going to be a different story. If you are trying to ripen the same amount of fruit later in the year, it probably just won't get ripe."

As the days get shorter, the growing time follows suit.

Vines work through the night during much of the growing season, but when days grow colder it takes temperatures above 62 degrees to stir the plant back into action.

Don Mixon of Daisy Creek Vineyard in Jacksonville said he anticipates a two-week wait before harvesting his Touriga grapes and figures it will be the end of October before riesling grapes are picked.

He said the crop load was substantial before he began whittling it down. "I dropped a large percentage to get a fighting chance at ripeness," Mixon said. "The interesting thing about this year is that the flavors — even when the fruit is unripe — are fantastic. If God is good and we have a nice warm October, it could be quite good."

There is some angst, Mixon said, concerning late-ripening varietals such as cabernet franc and cabernet sauvignon.

"Those folks are quite anxious and rightly so," Mixon said. "The rest of the varieties, certainly early varieties, will be fine. Basically, we're betting there will be no frost until early November and that's betting against history. But there have been years where we haven't had frost and it's a possibility that they will pull it out."

Perhaps the earliest harvest will begin on Friday at Agate Ridge on Nick Young Road outside Eagle Point

"We are picking sauvignon blanc earlier," said owner Kim Kinderman. "It gives us lower brix (sugar content) to get the style we're looking for."

Reach reporter Greg Stiles at 541-776-4463 or e-mail

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