Vineyard disease management, June 3

By Terence Bradshaw

Vines are growing rapidly in Vermont, we have shoots over 16” in the UVM vineyard, and we will be approaching the ‘immediate prebloom’ period when phomopsis, black rot, powdery mildew, and downy mildew are al active. Rain is expected Sunday June 5-Wednesday June 8, and low winds are expected tomorrow, June 4. I recommend that all vineyards be covered with an effective fungicide (or mix of fungicides) against these diseases. For IPM growers, that means a combination of a mancozeb or captan plus a DMI (Rally, Inspire, Rubigan, etc.) or strobilurin (Sovran, Flint, etc.). For organic growers, a fixed copper or Bordeaux mixture is recommended, this is your ‘big gun’ that will provide some control of black rot as well as other diseases in combination with a strict sanitation program.