Vines at West Madison Agricultural Research Station show a fair bit of frost-damage this week. The prevalence of frost-damaged shoots on an individual vines varies from 0% of shoots up to 47% of shoots damaged. By far the best indicator of how much damage was seen on vines was the location within the vineyard. On lower spots in the vineyards we observed on average 14% of the shoots were damaged, whereas higher areas presented on average 3% of shoot damaged. There also seemed to be a difference in damage between varieties, based on how far along the shoots were when the frost happened. For example, some of the further along varieties such as Brianna, Marquette, and La Crosse appeared to have more damage, while other varieties such as Petit Pearl, St. Croix and Valient showed less frost-damage in our plots.

At the Peninsular Agricultural Research Station, buds are much less developed, and temperatures only reached as low as 34°F, so damage is minimal.

This article was posted in Grapes, WFN, Vol. 1-4 and tagged Amaya Atucha, frost damage, Grapes, Janet van Zoeren.