How local wineries protect grape vines from cold weather

ONTARIO – A short drive across the border into Canada, along Lake Erie's North Shore is wine country, home to at least 17 vineyards. 

It's known as the Essex Pelee Island Coast or EPIC wine country. 

Weather is crucial to the wineries and vineyard managers are checking it all the time. In the winter, they work to make sure the grape vines are not killed by freezing temperatures. 

"We're always planning, planning ahead, you know, what is the next front bringing?" Peter Pfeifer, vineyard manager for Colchester Ridge Estate Winery.

It’s often referred to as CREW

Local 4 caught up with Pfeifer in late fall when he was hilling the grape vines to help protect them during the winter. 

"What we do is we take the soil and mound it around as a big hill around the plants so it's protected in a layer of soil," Pfeifer. "Even if you get really bad frost, which we had a couple years ago, that everything above ground freezes. We have enough live plant material in the soil that we can rebuild the plant."

Pfeifer said when it snows, that can also add another layer of insulation. 

If the cold kills the buds on the vines, then there is no fruit the following season and that means no wine. 

At Colchester Ridge Estate Winery, they have their own weather station to help give them readings at the surface and 40 feet in the air. 

"The weather station will give us readings remotely so we know when the temperature gets down to critical levels and then somebody gets up out of bed and gets here at 3 o'clock in the morning to start the fan to prevent the frost from killing our grapes," said Bernard Gorski, owner of Colchester Ridge Estate Winery.

The wineries use wind machines to push warmer air down on very cold nights. 

"Any time we're in a temperature range in and around 0 Fahrenheit , minus 18, minus 19 Celsius, we come out to run the wind machines and to help warm the air around the vine so they don't get to that temperature where the buds get killed," said Kevin Donohue, vineyard manager for Colio Estate Wines. "We can change the temperature that the vines feel by about 6 Celsius, 10 Fahrenheit or so, when we get around that 0 Fahrenheit area as long as it doesn't get colder than minus 10 or minus 12 Fahrenheit, we would be able to mitigate that temperature to stop vine death."

The wind machines are used in the early morning hours and only on still nights. 

“In many years it has helped us an awful lot to keep our crop, said Donohue about the fans. 

Donohue is responsible for 200 acres of vineyards for Colio Estate Wines. 

Protecting the vines is not a quiet proposition, on a calm still night with 11 eight-cylinder propellers running, it sounds like a row of helicopters waiting to take off. 

Donohue says they can get noise complaints, but under the Farm Act, vineyards are allowed to use the whatever machines on the farm that need to be utilized. People understand they employ a lot of people and provide a lot of product for the area. 

Nearby Lake Erie helps the wineries year round. 

"In the winter, it will protect us as a large body of water from severe winter freezes as long as the lake doesn't freeze over, and in the summer it will help us because we always have off lake breezes and the air is moving and it helps us to get the air moving in the vineyard and help to dry it up especially in the summer, in July and August when it gets very humid and sticky around here," Pfeifer said.

The vineyards say they partner with mother nature to produce good wine. 

When asked which season is the most challenging weather wise for the operation, Gorski said that is a trick question. 

"I think they all are. In the winter time you can get extreme cold, in the spring time you can get too much rain, in the summer time you can get too much heat, in the fall time, once again, rain can destroy your crop," Gorski said. "That's where a good winemaker will be able to take what mother nature's given them and produce the best possible product." 

The vineyard managers says there are usually around six or seven nights each winter they really worry about and usually end up running the wind machines three or four times a season. CREW winery said they are already watching the temperatures this Sunday night in case they get low enough for them to turn on their wind machine. The vineyard managers will be up monitor the weather all night long. 

For more information on EPIC wine country, visit the official website here.

About the Authors:

Ben loves his job at Local 4 because broadcast meteorology challenges him to crack Mother Nature’s code, then find new and creative ways to tell that story to people.