Blogs

Discipline: Grape pathology

Investigator: Mizuho Nita

Title: Virginia Grape Disease Updates

Description: Seasonal updates on wine grape disease management, extension meeting announcements, and other related topics from a grape pathology lab at AHS AREC.

Virginia Grape Disease Updates

Grape Disease Risks: 8/12-8/19/2026 and Downy Mildew Forecast Grape Disease Risks: 8/12-8/19/2026 NEWA is an Agricultural Weather Station Network, and we are part of the team. Here is a snapshot from last week showing the number of days with risk for each disease: Ph = Phomopsis, PW = Powdery...
Grape Disease Risk: 8/5-8/12/2026 and Downy Mildew Forecast Vine Status The majority of Chardonnay clusters are in the middle of veraison. For some reason, our Merlot dodged the frost, and its clusters started to accumulate sugars. Grape Disease Risks: 8/5-8/12/2026 NEWA is an Agricultural Weather Station Network, and we...
Grape Disease Risks: 7/29-8/5 and Downy Mildew Forecast Grape Disease Risks: 7/29 – 8/5/2026 NEWA is an Agricultural Weather Station Network, and we are part of the team. Here is a snapshot from last week showing the number of days with risk for each disease: Ph = Phomopsis, PW...
Weekly Grape Disease Updates, Seasonal Disease Management Reminders, and a List of short PHI materials. Vine Status We received much-needed rain (~0.9 inches) yesterday! Many Chardonnay, Chardonel, and Vidal clusters are getting soft and approaching veraison. Some others, e.g., Frontenac and many table grapes, are at different stages of veraison. Grape Disease Risks: 7/22-7/29/2026 NEWA is...
Grape Disease Risks: 7/15-22/2026 and downy mildew forecast Vine status Some table grapes started veraison. One early cultivar (Everest, not pictured) had one cluster survive the frost and start to accumulate sugar. Many Chardonnay clusters are at bunch closure. Vidal is at bunch closure; some others, e.g., Chardonel...
Grape Disease Risk: 7/8-7/15/2026 Vine status If anything, this year has been a Phomopsis year! These spots on the leaf in the picture are Phomopsis lesions. You do not need to manage this disease right now. We will manage them next spring. Many Chardonnay...
Grape Disease Risks: 7/2-7/8/2026 and Downy Mildew Forecast Vine status Still behind on canopy management, and vines are filling the canopy with many laterals. Some of the Chardonnay clusters on primary shoots are at bunch closure, and others are BB-size. Hybrids and table grapes are a bit more...
Grape Disease Risks: 6/24-7/1/2026, Downy Mildew Forecast, and EPA Public Comment Vine status Still behind on canopy management, and vines are filling the canopy with many laterals. Hybrids and table grapes are a bit more consistent with fruits. Vidal is pea-sized; some others, e.g., Chardonel, Frontenac, were almost at the bunch...
Grape Disease Risks: 6/17-24/2026, and Downy Mildew Forecast Vine status We hedged our Chardonnay vines this week. Still behind on canopy management, as you can see in the picture above. Hybrids and table grapes are a bit more consistent with fruits. Vidal is BB-size, some others, e.g., Chardonel,...
VA Grape Disease Risks:6/10-6/17/2026, and downy mildew forecast Vine status I found several third instars of spotted lanternfly (toward upper right, just below the catch wires) and ants enjoying their honeydew on a leaf. The situation is similar to last week. Our Chardonnay vines are reaching the top...