Organic winemakers in Germany expect huge crop losses in the coming months as a mildew overtakes vineyards after an unusually rainy summer.
But little can be done to fight the spread because of EU regulations, said Andreas Hattemeer, the head of the Association of Viticulturists in the western town of Oppenheim, in the heart of the country's winegrowing region.
"Reliable substances once used in organic viticulture can no longer be used by organic winemakers today," he said, referring to a compound known as potassium phosphonate.
EU regulations consider potassium phosphonate an effective fungicide to treat downy mildew, and at one time it was permitted for use on organic vineyards.
But the rule changed and it now cannot be applied to vineyards producing wines to be called organic. Instead, EU legislation states copper compounds must be substituted for the fungicide.
"Copper compounds are the most effective substances against downy mildew in organic farming," a 2014 EU technical report said.
To further complicate matters, when compared to other EU countries, Germany has stricter organic regulations. Most countries allow 8 kilograms of the copper compound per hectare per year; Germany only allows 3 kilograms per hectare.
"As an association we are asking that the EU allow us to use the substance in organic viticulture again," Hattemeer said, referring to potassium phosphonate.
Organic viticulture is virtually impossible given current EU regulations in a year such as this one, according to Hattemeer.
The environment minister in the central German state of Hesse also supports the return of potassium phosphate in organic farming, a spokesman said. Or at least the consideration of changes to the amount of copper compounds that are currently permitted on German farms.
In the German state Rhineland-Palatinate, the winegrowing ministry tried convincing organic winemakers to participate in an experiment with the substance, but they refused.
"No one wanted to risk losing EU funding," Hattemeer said.
According to Ernst Buescher of the German Wine Institute in Bodenheim, the situation will only grow more complicated.
"Climate change will only further accelerate extreme weather phenomenon," he said. "As will the demands on the winemakers."