The European Union is considering severely limiting the use of copper sulfate to fight mildew in vineyards; organic farmers argue fungus will run rampant without it. Suzanne Mustacich gathered several opinions for Wine Spectator.
It's a top tool of organic grapegrowers. But is copper sulfate truly safe for vineyards? A new push by European leaders to reduce—and eventually eliminate—copper compounds used by organic and biodynamic winegrowers is making the future of organic viticulture uncertain in some wine regions.
Vintners say that without effective alternatives to copper, crop loss in damp years will make organic vineyards economically unsustainable, forcing them to turn to synthetic chemicals or bankruptcy. But as the E.U. moves toward a vote on whether or not to reauthorize the use of copper compounds, leading winemakers argue that Europe's current approach to organic farming is too simplistic, and advocate a more nuanced strategy.
"Natural is good, synthetic is bad? It's too basic to reason that way," said Charles Philipponnat, CEO of Philipponnat Champagne. "The objective is to make fine wine in a way that doesn't leave a negative impact for our children."
Since the 1880s, copper compounds, typically copper sulfate mixed with lime, have been used by grapegrowers to fight fungus and bacteria threats to vines. For organic growers, who cannot use modern fungicide sprays, copper sulfate remains the most effective weapon against downy mildew. While wine grapes were the original target crop, copper compounds are also widely used for organic potato, tomato and apple farming.
But risk assessments by public authorities like the European Food Safety Authority (EFSA) show that copper compounds pose risks for farm workers, birds, mammals, ground water, soil organisms and earthworms. These risks make copper unpalatable to many vintners.
"Copper is a heavy metal and it stays in the topsoil. It's not natural; it's not clean," said Philipponnat. While his Champagne house has eliminated herbicides and chemical fertilizers and uses natural vine treatments, he doesn't rule out synthetic remedies. "I don't think it's bad to use synthetic molecules. Some synthetic molecules disappear much more rapidly. Some synthetic treatments are better than copper, but they aren't accepted for organic viticulture."
Can organic farming endure with less copper?
Nearly 17 percent of Italy's vineyards are certified organic. In France, 10 percent of the country's vineyards are certified organic or in the process of certification. In Italy, Hungary and Slovenia, roughly half of small and medium-size estates are organically farmed.
Under current E.U. rules, certified organic growers are allowed to spray about 5 pounds per acre per year. But there is also a so-called smoothing mechanism: Growers can spray more in wet years as long as they don't exceed 27 pounds per acre over a five-year period.
"In some areas they used [6 pounds per acre] this year," said Lorenza Romanese, policy advisor for the E.U. Confederation of Independent Growers.
Those days are numbered. E.U. lawmakers are currently leaning toward a 25 pound per acre limit over a seven-year period (3.5 pound per acre per year average) starting in January 2019. Initially, E.U. lawmakers did not include the "smoothing mechanism," but the French predicted more than half of the organic vineyards would return to conventional farming. Lawmakers acquiesced to a smoothing mechanism.
"At least we're not dead," said Romanese. "For all of Europe, with the smoothing mechanism, we can survive." But he says organic farming will shrink. "We lose Champagne and a few regions in the Loire. The Prosecco region and Trentino–Alto Adige, those two won't make it with [3.5 pounds]."
In Burgundy, Philippe Drouhin of the Beaune-based merchant house Joseph Drouhin, told Wine Spectator, "I think that will be a hard challenge for all of us, big and small estates."