The blast of Arctic air chilling B.C. right now is keeping Okanagan ice wine makers busy.

Rickard Branby, the manager of Sperling Vineyards in Kelowna, was out on Thursday morning with six others picking grapes in the –12C temperatures.

The picking usually happens just before dawn. Brandy says it's the second good morning they've had for this harvest.

Ice wine

Ice wine can only be made from grapes that are still frozen on the vine, causing the water to freeze and resulting in a much sweeter dessert wine. (Dave Chidley/Canadian Press)

"We picked half yesterday morning and we are picking half now too, so we will be done here in about two and half hours."

Ice wine can only be made from grapes that are still frozen on the vine, causing the water to freeze, concentrating the juice and resulting in a much sweeter dessert wine.

"It has to stay cold throughout. It can't go above –8C," he notes.

Not too late for harvest

One of the blocks of grapes being harvested today is the oldest block of Riesling vines in Canada. It will be used for a late harvest wine.

Unlike ice wine, late harvest wine is made from grapes that have been left on the vine longer than usual and have naturally dehydrated by noble rot, a mold that makes them look like raisins.

"When it warms up about 8 a.m. we can go up to the vineyard and pick the late harvest we started yesterday. So we will be done picking about 11 a.m. today," said Branby.

But the work does not end there. Once the grapes are picked, they need to be put into production immediately.

"[Then] I will take them up to the winery and put them in the press... I will probably take all day."

Ice wine pickers

A crew of hardy pickers braved the subzero temperatures this week to bring in the ice wine harvest at Sperling Vineyards. (Rickard Branby)