Bud Hardiness Data
Grapevine Cold Hardiness Monitoring
Winter low temperatures that fall below a critical value can damage grapevine buds. The critical temperature for bud injury varies over the dormant season, and responds to daily changes in temperature. We can measure this critical temperature through a procedure called differential thermal analysis, which involves controlled freezing of a sample of buds collected from vineyards. In 2021-2022, we are modifying the monitoring plan used in previous years and are now reporting cold hardiness for 12 cultivars.
We monitor samples weekly from November to March, and every two weeks for samples from Finger Lakes and Lake Erie vineyards between mid-winter and March.
The data presented here is part of the Fruit Crop Physiology Research and Extension program at Cornell University. Below is a link to our new interactive cold hardiness app. Please give it a try and let us know if you experience any problems with the interface.
Testing Cold Hardiness
Each winter, Cornell Extension staff from the Finger Lakes, Lake Erie and Hudson Valley regions collect samples of grape buds to test their ability to withstand cold temperatures. Grape growers use this information to make decisions about their pruning strategy during the dormant season in order to retain enough fruitful buds to ensure an adequate crop the following growing season.