A cold-hardy wine grape. Developed at the University of Minnesota, this blue-black grape can withstand cold temperatures as low as -30°F and still produce grapes for making a good quality wine with a pleasant cherry aroma. Frontenac has been a consistent heavy producer and vigorous grape variety with a good resistance to powdery mildew and near-immunity to downy mildew. Grapes are produced on medium to large clusters that are usually slightly loose resulting in minimal berry splitting and bunch rot. Ripens in late August to mid-September. Self-pollinating.