For French winemaker Thomas Ventoura, the spring frost that hit the Chablis vineyards of northeast Burgundy over the weekend has a bitter taste of déjà-vu.

Just as at the same time last year, Ventoura and his workers had to rush out and place hundreds of candles across his vineyards before daybreak to warm the vines and prevent the destruction of already well-developed shoots by temperatures that had plunged below freezing.

Chablis is a very dry white wine that is produced only in the Yonne region of Burgundy due to the area’s specific climate. But volumes could now be under pressure as the emergence of mild weather early in the year followed by a spring frost, previously unusual, looks to becoming a recurrent trend.

“Since 2016, there have been three big frosts,” Ventoura, 34, said. “We’re now starting to wonder about the future of our business at this time of the year.”

The change in weather pattern is also pushing up his insurance coverage for loss of harvest, he added. In Yonne, two thirds of the harvest was destroyed as a result of the frost last year, according to the farm ministry.

“There's a lot to be done in changing viticulture practices... in the context of climate change,” said Mathilde Civet, 25, a viticulture adviser to the Chambre d'Agriculture in Yonne, the local representative body for the farming sector.

Winemakers were starting to join forces to invest in new tools, such as heating cables, to help mitigate the effects of such frosts, she said.

However, many in the industry are still reluctant to face up to the fact that the impact of climate change could be long lasting, Civet said.

“The recent episodes of drought and frosts have been a wake-up call for some, but in previous years there was a sort of denial.”