Grape Disease Risks: 9/16-9/23/2026

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 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. Note: Since we are out of the critical period for black rot and Phomopsis, you can ignore them.

Unfortunately, NEWA’s downy mildew model is down this week. Please see below for the downy mildew forecast. As we discussed in the previous virtual vineyard meetings, we still need to maintain our vines to ensure healthy canopies that support bud formation for next year, cane or spur selection, and winter survival. 

For detailed recommendations, please refer to the previous week’s posting.

Downy mildew forecast

Please click the table above to enlarge. The forecast looks promising next week.

The downy mildew forecasting effort is supported by the Virginia Wine Board.