If there are signs of powdery on bunches, like the one shown above, in your vineyard, apply two sprays of a suitable registered fungicide at 10-day intervals in attempt to stop the disease increasing.
When protecting for Powdery avoid spraying wettable sulfur at high temperatures (>350C) when the humidity is >70% within 24 hours of spraying. Growers can opt to use Legendtm in hot weather to avoid sulfur burning. This allows them to keep up the protection on their vineyard.
Comments