Some of our early cultivars such as Alandale is changing it color. It is just a matter of time to see other cultivar to enter phase of veraison. Hopefully, we will keep seeing dry weather with little bit of rain here and there.... There are several diseases to be considered at this stage. One of them is Botrytis. The spray timing for Botrytis is at bloom, bunch closure, and veraison. The pathogen seems to be active throughout the season, but Botrytis likes berries when they get mature and accumulate more sugar. As usual, canopy management is the first line of defense against grape disease management and this is particularly true for Botrytis since it tends to develop after a long period (15-17 hours) of high humidity condition. Please keep in your mind that Botrytis is very well known for its capability to overcome fungicides. Thus, a rotation of mode of action groups is very important aspect for Botrytis management. The mode of action for a particular fungicide ca
Grape Disease Management Tips from Mizuho Nita (Grape Pathologist at Virginia Tech)