Losses incurred by a historic bout of frost in early spring were compounded by the emergence of diseases blamed on the wet summer.
French wine production is expected to fall by nearly a third this year due to a devastating bout of frost in early spring.
The Ministry of Agriculture's statistics agency, Agreste, estimates that production of wine should plummet 29% year on year to about 33 million hectolitres. This is about a quarter below the average for the previous five years. A hectolitre = 100 litres.
"The spring frost has cut into a large part of the production, which will be historically low," Agreste said in a statement on Tuesday.
Desperate wine-growers attempted to ward off the late frost by lighting candles and fires in their vineyards at night and spraying water to create a shell of ice around the buds.
Still, none of the wine-producing regions was spared by the frost but those harvesting early ripening grape varieties were most impacted, with the Burgundy, the Rhône Valley and the Jura particularly badly hit.
Losses were then accentuated by the wet summer which favoured the emergence of disease, Agreste said, including powdery mildew and black rot. The necrotrophic fungus botrytis is now also threatening harvest, especially in Alsace.
2021's yield should be close to the one of 1977 when the wine harvest was also severely reduced by a destructive frost and summer rainfall.
The eastern Jura region should see a precipitous year-on-year fall of 82% in its wine production to just 17,000 hectolitres. Beaujolais is next with production forecasted 47% below that of 2020, while the amount of wine produced in the south-west — excluding the Bordeaux region — should slip by 44%.
Production of Champagne should be down 36%. Agreste said "agronomic production (in the Champagne region) should be the lowest in 40 years, which should lead to the use of wine reserves from previous years."
France is the world's second-largest wine producer after Italy and the largest exporter.