Voltis Grapes Yield Clusters Over 600 Grams in Champagne’s First Climate-Resilient Harvest

This year marked the first harvest of Voltis grapes in Champagne, a significant step for the region as it adapts to climate change. Voltis is a white grape variety bred for resistance to downy and powdery mildew, two diseases that have long challenged vineyards. Only 8.9 hectares of Voltis are currently planted in Champagne, mainly in buffer zones near residential areas or in locations especially vulnerable to mildew.

The introduction of Voltis is part of a broader initiative known as VIFA, which aims to help French vineyards respond to changing environmental conditions. Heloïse Mahé, who leads the grape and wine quality department at Comité Champagne, said that growers are still learning about the new variety. “We are learning to get to know it,” Mahé explained. She noted that Voltis ripened at the same time as other traditional varieties, even though experts had expected it to be ready for harvest about a week later.

One of the most notable surprises from this year’s harvest was the size of the grape clusters. Some clusters weighed more than 600 grams, a fact that quickly spread on social media among industry professionals and enthusiasts. Mahé pointed out that compared with Chardonnay, there are half as many clusters per square meter with Voltis, but each cluster is about twice as large.

Weather conditions this year contributed to higher sugar levels in the grapes. The average alcohol content reached 9.8 percent, slightly above the usual range for Voltis, which is between 9 and 9.5 percent. For the 600 kilograms of Voltis grapes fermented by Comité Champagne as part of ongoing trials, the average alcohol content was measured at 9.95 percent, with total acidity at 6.4 grams per liter and a pH of 3.10.

Comité Champagne is conducting small-batch winemaking experiments with six different strains commonly used in the region, including Voltis. To support these efforts, a network of 80 industry members has been established to share information about vineyard management techniques specific to the new cultivar. Among these growers, a dozen have been asked to document their technical choices in detail.

In January, Comité Champagne will bring together these growers to discuss their experiences with winemaking using Voltis. Early feedback suggests that Voltis can add color to the juice and may develop bitterness on the finish—qualities that will be closely monitored as research continues.

A final decision on whether Voltis will be included in the official specifications for AOP Champagne production will not be made until after the 2032 harvest. Until then, growers and winemakers will continue to study how this new variety performs in both the vineyard and the cellar, as Champagne seeks ways to maintain its reputation while facing new environmental challenges.