Marquette grape vines
We have 10 Marquette grape vines in our backyard, and over the last two weeks the grapes have developed blackness. We pruned them in February and they seemed to be doing really well. I sending pictures in hopes that you may be able to advise us as to the best course of action. Should we dig them up? Can they be saved?
Howard County Maryland
Unfortunately, your grapes are infected by one of the most damaging and common fungal diseases of grape- black rot.
It is essential to remove and discard as much of th infected fruit as possible to reduce disease incidence next year.
The fungus causes leaf symptoms early in the season and then infects the fruit. Spraying preventatively early in the season (when shoots begin to elongate) is essential.
Immunox is one of the better chemical fungicides available to home gardeners for controlling this disease. We refer gardeners to the VA Tech spray recommendations for controlling fruit insect pests and diseases. jt