Growing Concord Grapes in the North
I would like to grow concord grapes. Will they survive Wisconsin winters?
Concord grapes will be injured or killed when temperatures reach minus 20 degrees, but cold winters are only part of the challenge. These grapes need 155 to 160 days for the fruit to mature. A cool summer or early fall frost can result in poor quality or frost damaged harvest. Only southern Wisconsin gardeners (zone 5) should attempt to grow concord grapes. Even in this area you may only get a good crop two or three out of every five years. I recommend you try some of the hardier concord alternatives like Bluebell, Fredonia, Van Buren, and Worden. University of Minnesota is an excellent resource as they are continually researching hardiness of grapes as well as other edible and ornamental plants.