It has been a difficult start to the year for many. Frost has been persistent in this relatively “early” growing season. The most recent frost events have occurred late enough that tissues likely would have been damaged if a frost occurred on a similar calendar date in several previous seasons.

Frost damaged shoots on a mature Merlot vine. (photo courtesy of Eric Case)
Frost damaged shoots on a young Petit Verdot vine. (photo courtesy of Larry Lykins)

On March 5, a blog post addressed frost protection. This post may be of lesser concern now. But some may still yet be at risk of experiencing a frost. Here is a link to that post: https://site.extension.uga.edu/viticulture/2020/03/vineyard-frost-protection-considerations/

What now? My suggestion is to be observant over the next several days. Implement integrated pest management to protect the health of secondary shoots. Though less fruitful, the foliage produced on secondary shoots will conduct photosynthesis to assimilate carbon throughout 2020. Maintaining healthy green vine tissues will optimize carbon gain and promote perennial vine health and sustainability. In situations where frost has damaged green tissue on healthy and mature vines with ample carbon reserves, secondary growth may be strong. In situations where frost has damaged green tissue on unhealthy, small, and/or young vines with a deficit of carbon reserves, secondary growth may be weak. Makes observations in your vineyard and act on what you see. This will be a good year to see how different cultivars respond to primary shoot damage or death. In general, secondary buds are more fruitful in hybrid relative to vinifera cultivars.

Dr. Dave Lockwood, Professor and Small Fruits Extension Specialist at the University of Tennessee, kindly shared the following document. While many publications address frost avoidance, relatively few publications address what to do and consider after a frost has occurred. Dave does a nice job summarizing post-frost event considerations. Thank you, Dave.

I wish everyone the best in getting through this difficult start to the growing season and moving on to a productive rest of the season.