With this latest temperature drop I thought that I would take a walk through the vineyards to check for coverage of the canes. The good thing, if there is any good at all from cold weather, we had some snowfall accompanying the cold snap. What I was looking for other than some exercise, was exposed fruiting canes that had some soil washed off with the rains we received a few weeks back. Grapes produce fruit on 1 year old wood or canes and deep cold snaps can cause damage to these canes. So here in beautiful Prince Edward County, besides having great soils for growing grapes, and long dry summers, we have colder winters than Niagara which can cause damage.
The killing temperature of Vinifera, Pinot Noir, Pinot Gris, Chardonnay etc…is -23 degrees Celsius. Hybrids such as Baco Noir are hardier than Vinifera. Although the killing temperature is -23 for Pinot Noir, damage starts to occur at -12 or even warmer if there is damage from mildew or other diseases. This damage can limit next years crop, by killing or injuring the Primary buds on the cane. Baco Noir and Vidal are hardy to about minus 27. While Marechel Foch is hardy to -30, Minnesota hybrids, such as Frontenac and Frontenac Gris, which were bred by the University of Minnesota are hardy, to about -40.
To avoid the damage caused by the winter cold, here in the County we bury some of the canes. Essentially with Vinifera we bury or lay down 1 or 2 canes each way from the vine. These canes are then “hilled up”. Hilling up is completed after harvest, obviously, and before the ground freezes. Basically the same you do to roses to protect them from the cold, but on a much larger scale. This is done with a grape hoe on the side of the tractor and a vplow off the back of the tractor. The higher the hill, the more dirt on the canes, therefore the more protection on the canes. This dirt then needs to come off in the spring which we will cover when its warmer.
So now lets sit back by the fire and enjoy a glass of County Pinot.