—story by Ross Courtney
—photos by Ross Courtney and Matt Milkovich
After a few harsh winters, wine grape growers in chilly areas are showing more interest in cold-hardy vines.
Breeders and nurseries say they have been fielding more calls and taking more orders for hybrid varieties that better withstand extreme cold events, such as those that caused extensive damage in British Columbia the past three winters.
Hybrid genetics can offer “bomb-proofing against climate change,” said Tom Plocher, a grapevine breeder from Hugo, Minnesota, who specializes in cold-hardy cultivars.
To get the right combination of cold resistance and coveted wine flavor, Plocher and other breeders cross North America’s native grapes with V. vinifera varieties that originated in Europe, such as Cabernet Sauvignon and Chardonnay, and then select the progeny over six, seven or more generations.
In November, Plocher spoke at the Washington State Grape Society’s annual meeting in Grandview, describing the traits of the top 10 commercialized cold-hardy grapes. He followed the presentation with a wine tasting at the nearby Yakima Valley College campus. Some of the wines were produced with cold-hardy varieties bred by him, some by the University of Minnesota, some by other individual breeders.
One of his major points was to provide some nuance to the advertised cold levels of the varieties. Yes, some vines really can survive to their purported minus 30 degrees Fahrenheit, but only if they have been acclimated. They need what he calls “cold stimulation,” gradual exposure to cold starting in September followed by lowering temperatures until the thermometer hits subzero by December and January. Without cold stimulation, the vines won’t be as hardy in the face of extreme temperatures.
Another viticultural point: Cold-hardy vines have high survival rates for both primary and secondary buds, which is not the case with V. vinifera. Typically, secondary buds produce smaller clusters and, depending on when the primary buds are damaged, the secondaries may get a later start on their growth, pushing back harvest, he said. But it’s better than losing a crop completely.
A February 2023 advective cold in Nova Scotia, where resistant hybrids are planted beside V. vinifera, provided a natural experiment. The European cultivars had zero percent bud viability from primary buds, and little more on secondary buds. On cold-hardy vines, an average of 32 percent of primary buds survived and 47 percent of secondary buds, Plocher said.
Grower interest
Meteorologists say erratic weather events in either direction of the thermometer are becoming more common with climate change. Growers are showing increased interest in grapevines that can withstand those swings.
“It’s definitely grown,” said Kevin Judkins, owner of Inland Desert Nursery in Benton City, Washington.
The nursery has demand beyond its supply for cold-hardy hybrids among commercial and hobby growers in British Columbia and Ontario, he said. To keep up, the nursery has expanded its mother blocks of hybrids, from about 50 vines to 300 vines each. Among them are Plocher’s Verona, Crimson Pearl and Veritage, as well as varieties from Cornell University and the University of Minnesota.
Quails’ Gate Winery in Kelowna, British Columbia, has established an evaluation block of about 15 cold-tolerant varieties, each with 250 vines, at an especially cold site east of town, removed from the moderating effect of Okanagan Lake.
The company hasn’t yet committed to any of them, said Jeff Del Nin, senior winemaker. He wants to see what kind of wine they make over the next few years.
“We just need to start thinking about the future,” he said.
The past three winters in the province’s Okanagan Valley, a rising star in Canada’s overall wine production, have featured destructively deep cold spells, causing a near total crop loss in 2024. Under a lifting of provincial regulations, wineries that haven’t closed have been allowed to import grapes from the U.S.
Quails’ Gate normally harvests between 1,000 and 1,200 tons of grapes from its own vineyards. In 2024, that fell to 75 tons. Del Nin spent 51 days in California, Oregon and Washington to purchase grapes — and to keep the doors open and 100 employees at their jobs.
The hybrids may allow him to restructure his vineyards to reduce the impact “next time Mother Nature throws us a devastating curveball,” he said.
Del Nin hesitates to blame climate change. British Columbia has a long history of horrible winters. Cold-hardy vines aren’t new, either. They just fell out of favor as producers, with help from federal and provincial governments, converted to V. vinifera in the 1980s and 1990s to keep up with the new market demands ushered in by increased trade between the United States and Canada.
Quails’ Gate still has some Marechal Foch, a French hybrid that ripens early, tolerates cold and resists fungal diseases. Planted in 1965, those vines did not suffer any winter damage.
The newer cold varieties make good wines, said Kaibab Sauvage, co-founder and grower at Sauvage Spectrum, a vineyard and estate winery in Palisade, Colorado, also known for its cold winters. However, the new varieties can be a tough sell with winemakers and customers who prefer flavors they are used to.
“We started calling them New World cultivars,” to boost appeal, Sauvage said.
Northern breeders such as Plocher or university researchers who create these new cultivars have to think about more than just withstanding the deep dregs of winter. To avoid increasing freeze risk in spring and fall, breeders also search for species that go dormant early and emerge late. Some V. vinifera varieties are already good about that; Chardonnay, for example, harvests early and hardens quickly.
After a 2014 deep cold, Sauvage began planting cold-hardy varieties. Today, about 15 of his 60 acres are the resilient hybrids, including Plocher’s Petite Pearl and Marquette, a University of Minnesota red grape released in 2006. And one day in fall 2020, Sauvage was still harvesting grapes in 40-degree weather before temperatures plummeted to 18 that night.
“What Tom’s doing is so cool,” Sauvage said. “Can we breed our way out of this?” •
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