In organic viticulture, which practice is allowed?

• A. Use of synthetic fertilizers
• B. Genetically modified vines
• C. Sulfur and copper sulfate
• D. Broad-spectrum chemical pesticides

Answer: (C)

In organic viticulture, the goal is to manage vineyards with inputs that are approved for organic standards and to rely as much as possible on preventive practices. Among these, sulfur and copper sulfate are traditional, permitted tools for disease control. Copper sulfate acts as a fungicide to help manage downy mildew, while sulfur helps suppress powdery mildew. They’re allowed within specified limits because they’re considered natural or minimally processed inputs and have long-standing use in organics.

The other practices are not allowed under standard organic rules: synthetic fertilizers are prohibited because they rely on highly processed inputs and can alter soil biology; genetically modified vines are not permitted because organic standards require varieties to be non-GMO; broad-spectrum chemical pesticides are restricted because they can harm non-target organisms and lead to resistance.

So the practice that’s allowed is using sulfur and copper sulfate, with proper management to avoid overuse and soil buildup.