After the extreme cold temperatures much of the US experienced this winter, many grape growers are  concerned about winter injury to buds and trunks. In the Finger Lakes region of New York, for  example, up to 90% of the primary buds on some V. vinifera cultivars were killed.
 
Cold-hardy University of Minnesota and Swenson cultivars can withstand much colder temperatures  than most other grapes, but it’s still advisable to assess your grapes for winter damage before pruning,  and adjust your bud number accordingly. If more than 20% of the buds are dead, you’ll want to leave more buds to maintain a normal cropping level.

The Northern Grapes Project has published some online resources to explore to learn more about how to assess winter injury and manage winter-damaged vines.

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