PROSSER, Wash. — Washington’s 2019 wine grape harvest has been damaged by rain and freezing weather but how much is not yet known.
One of the wettest Septembers in a long time spurred outbreaks of disease and rot. Then a hard freeze the nights of Oct. 10 and 11 with temperatures into the low 20s killed leaves, stopping grapes from ripening.
Grapes that were ripe before the freeze are still being harvested, but large portions of those that weren’t ripe won’t be.
“I don’t have the numbers but I would say the frost historically speaking was one of the toughest we’ve had. It was really early and cold. It’s significant. We expect to have some tonnage losses,” said Kevin Corliss, vice president of viticulture at Chateau Ste. Michelle Wine Estates, the state’s oldest and largest winery. It’s headquartered in Woodinville, near Seattle, but most of its vineyards are in Central Washington.
The state's vineyards harvested 260,000 tons of wine grapes in 2018, down from the record 270,000 tons in 2016. This year’s forecast matched that but now probably will fall short.
Even before the freeze, wineries were limiting growers to exact commitments because of a temporary oversupply, said Wade Wolfe, winemaker at Thurston Wolfe Winery in Prosser.
“They aren’t taking any extra fruit and will be asking some growers to leave it out there on the vines,” he said.
It’s just normal cycles of supply and demand and the fifth time the industry has been in over supply since the late 1970s, he said.
“We got a later start this year because while July and August were close to average temperatures, September was below average, which slowed ripening, and picking got delayed,” Wolfe said.
“With rain we had some rot issues with rot susceptible varieties so there’s been some picking to avoid that,” he said.
An Oct. 2 frost was mild enough that most vineyards were unaffected but the Oct. 10 and 11 freeze was severe and widespread.
Some vineyards were untouched by the freeze including Ryan Flanagan and Milbrandt Vineyard’s large Spanish Castle vineyard 20 miles southeast of Wenatchee.
“We’re doing just fine but for the industry it's hard to say,” Flanagan said. “The hard frost took the canopy and stopped ripening on a large portion of the crop. If it was ripe you can pick it and get it in. If not, it’s done.”
Sugar levels are too low in unripened fruit, but some of it can still be used for juicing, Corliss said.
Flanagan, who manages Milbrandt’s Evergreen and Ancient Lakes vineyards near George, said Milbrandt’s vineyards there and on the Wahluke Slope mostly escaped damage.
Wolfe said higher elevations and steeper sloped vineyards were less likely to have damage.
A challenge for machine harvesting has been avoiding getting too much dead leaf and stem debris, he said. Particularly with red wine grape varieties, too much debris is not good in fermentation, he said.
Wolfe estimated industry-wide harvest at 80% complete as of Oct. 17 with last pickings to finish, as usual, the first week or two of November.