Vineyards in B.C.'s Okanagan test new ways to mitigate extreme cold

Winemaker Rowan Stewart is testing four long strings of vacuum-sealed, infrared LED lights. (Tom Popyk/CBC - image credit)
Winemaker Rowan Stewart is testing four long strings of vacuum-sealed, infrared LED lights. (Tom Popyk/CBC - image credit)

Bobby Arcego pulls back a thick layer of straw, exposing the young grapevine underneath.

As vineyard manager of Black Hills Estate Winery in Oliver, B.C., this is one of the new methods, he's using to try to protect this year's crop.

Last year, extreme cold wiped out 95 per cent of B.C.'s wine grapes.

"We saw temperatures dip down to -27 degrees, even some -29 degrees in areas around here, and that caused us to see extensive damage and death with our vines," said Arcego.

"If we can't protect against the cold weather, we're going to be questioning if it's a region that we can grow wine grapes in."

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Another method he's using involves geotextiles — a white fabric that helps trap heat generated by the earth.

One method to protect grapes is geotextiles — a white fabric that helps trap heat generated by the earth.
One method to protect grapes is geotextiles — a white fabric that helps trap heat generated by the earth.

One method to protect grapes is geotextiles — a white fabric that helps trap heat generated by the earth. (Tom Popyk/CBC)

Arcego says even a few degrees can make a difference, especially during an extreme cold snap.

"The crust of the ground has frozen, but down below that, it's still warm, and it's still producing heat that's going upwards," he said.

WATCH | How burying vines protects them from the cold:

They've also begun hilling. It involves piling up soil and composted mulch over the vine base and onto the first few inches of the plant to help insulate it from the cold.

"It's a very common practice in other cool climate regions in the world," said Arcego, "We just haven't had to use it here in the Okanagan quite yet."

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Will these methods work here?

Ben Min Chang, a research scientist for Agriculture and Agri-Food Canada, says techniques like hilling can easily be adopted across the Okanagan.

The downside is that this is more labour-intensive and comes at a cost.

Chang says this might reduce how fast growers are willing to adopt this technology.

His work as a researcher at the Summerland Research and Development Centre involves measuring temperature differences between insulated and exposed vines.

Researcher Ben Min Chang has freezer trays full of vine samples. They allow him to test cold protection methods.
Researcher Ben Min Chang has freezer trays full of vine samples. They allow him to test cold protection methods.

Researcher Ben Min Chang has freezer trays full of vine samples. They allow him to test cold protection methods. (Tom Popyk/CBC)

His freezer is full of trays of vine samples — which allow him to test cold protection methods.

"Unfortunately, the current European wine grapes are super tender," said Chang, who encourages replanting with new varieties of hybrid grapes that can withstand the cold.

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The unknown, he says, is how the hybrids would taste.

Not a cheap fix, but worth it

Winemaker Rowan Stewart has found a high-tech solution for Quail's Gate Winery in Kelowna.

It also saw devastating damage last year and lost its full crop— acres of vineyard.

They've replanted about 50 per cent of their vines and have been testing four long strings of vacuum-sealed, infrared LED lights.

Stewart describes it as working like the sun and says that one of the benefits is that it's not affected much by the wind.

"It doesn't really try and warm the air. It's warming the vine itself."

It's not a cheap fix, costing between $10,000 and $20,000 an acre. But Stewart says the warmth they give off is worth it.

Winemaker Rowan Stewart says that even if the infrared LED lights only save one crop, they'll have paid for themselves.
Winemaker Rowan Stewart says that even if the infrared LED lights only save one crop, they'll have paid for themselves.

Winemaker Rowan Stewart says that even if the infrared LED lights only save one crop, they'll have paid for themselves. (Tom Popyk/CBC)

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"Imagine it's -26 C," he said. "If you can warm six degrees and get to negative 20, you've gone from having a crisis like we had last year to maybe just a bad crop — or maybe even having a full crop, depending on how you prune."

Stewart has priced it out and figured that even if it saves one crop, it pays for itself. And that doesn't account for the cost of the wine that comes from the fruit saved.

"The upside is huge. You only need to save one year, and it'll work," he asserts. If the trial works, he'll expand the method to a larger block of vines next year.

Stewart remains optimistic that grape growers will be able to figure it out.

"Once someone figures out the best method, or the most economical method or two, that's going to spread very quickly through the valley, and we're all going to start doing what works," he said.

"I'm pretty confident we'll find a solution, and we'll be back making amazing Pinot Noir and Chardonnay in a couple of years."