The proportion of fungus-resistant grape varieties in Switzerland is 3%. Interest in them is growing steadily, and not just because of this year's capricious weather. The question arises: which varieties are best and how well are they protected against powdery mildew and downy mildew? PIWI pioneer Edy Geiger from Thal (SG) reveals his assessments below. They are supplemented by the perspective of Roman Baumann, who, together with his family in Turtmann (CVS), is growing a wide range of PIWI.
Source: DIE ROTE - Swiss journal for fruit and wine growing 13/2021
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