Vine status
It has not changed much from last week. Temperatures have been relatively low, and the shoot growth rate remains slow. However, I observed some improvements (e.g., growth from basal buds, secondary buds, etc.) in hybrids and table grapes. Let’s hope that we will get some secondary shoots coming up for wine grapes, too. If you have not had a chance, please see my previous post about disease management after the frost event.
(Side note: Believe it or not, Summerset and Concord (both are table grapes) are at trace bloom this week. Summerset is a very early cultivar, but I am surprised by Concord.)
Disease risks 4/30-5/6/2026
NEWA is an Agricultural Weather Station Network, and we are part of the team. Here is a snapshot from the last week, showing the number of days with the risk of each disease: Ph = Phomopsis, PW = Powdery mildew, BR = Black rot, and DM = Downy mildew. N/A means there is no data or issues with the NEWA. I am waiting to hear back from the weather station company about fixing the one in Stafford.
There are some locations with 2-3 days of downy mildew risk events in the last seven days.
The low temperatures most likely did not favor disease development.
Downy mildew forecast
It looks like the model is calling for downy mildew infection events next week (Click to enlarge the table). As usual, prevention is the best approach. Please refer to my previous post about downy mildew management.
The downy mildew forecasting effort is supported by the Virginia Wine Board.
