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

Disease risks 5/21-5/27 and downy mildew forecast Vine status Probably because of the cooler temperature, the vines did not move as much as I hoped. As with last week, many Chardonnay shoots do not bear flower clusters, and relatively strong shoots are from the main trunks. Hybrids...
Disease risks from 5/13 – 5/20 and downy mildew forecast Vine status Things are finally moving. I saw quite a few shots from the secondary (or tertiary) buds coming up strongly, especially from the central part of the canopy (i.e., from trunks). However, many do not have flower clusters. Hybrids...
Grape Disease Risks: 5/6 – 5/13/2026, downy mildew forecast, and pre-bloom disease management considerations Vine Status Things are still slow, but moving. Our Chardonnay vines started to push secondary buds. On the other hand, some primary buds that survived the freezing events are developing rapidly. These staggered phenological stages will make disease management tricky....
Grape Disease Risks from Last Week, and downy mildew forecast 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....
Grape Disease Risks from the last week, Mancozeb and Isomate Z Updates. Vine status I was hoping to see some progress by now, but since the temperature has been relatively low (or maybe normal for this time of the year), vines have been relatively slow. I saw some movements with hybrids and...
Frost, disease risks, and a downy forecast Vine status Unfortunately, many of our vines were affected by the frost event yesterday. I have heard from Northern VA, the Shenandoah Valley, and Central VA, with varying degrees of loss. I lost about 80% of the Chardonnay shoots, about...
VA Grape Disease Risks: 4/8 – 4/15/26 and downy mildew forecast Vine status Our Chardonnay vines have grown quickly and are now about ~2 inches in shoot length. We lost about 10-15% due to the frost event that happened on 4/8/2026. Grape disease risks from the NEWA NEWA is an Agricultural...
Early Season Disease Management Reminders Phomopsis cane and leaf spot One of the diseases you need to consider soon after bud break is Phomopsis cane and leaf spot. It causes minor leaf spots, which are more evident to the eye, but necrotic lesions cause more...
Announcement from the Virginia Pesticide Collection Program Please see the information below for Pesticide Collection! Virginia’s Pesticide Collection Program assists agricultural producers, licensed pesticide dealers, pest control firms, golf courses and homeowners with the proper disposal of unwanted pesticides. The program is an effort by the Virginia...
2026 Monthly Virtual Viticulture Meetings We will host the 2026 Monthly Virtual Viticulture Meeting. Following last year’s format, we will hold meetings on the first Thursday of each month at 1 PM. The first meeting will be on 4/2. Our viticulturist, Dr. Drew Harner, and...