Harvest: Why the harvests are breaking an earliness record this year

Taking the first cuts of the pruning shears into the vines before August 15th was unheard of for over a century in the Var region. This summer, the winegrowers of the Terres Ailées cooperative in Gonfaron, north of Draguignan, began their harvest on August 13th. In the local press, Eric Pastorino, president of this cooperative and of the interprofessional association of Provence wines, considers that "a symbolic milestone" has just been reached.

Another notable fact this year: the very small gap between the start dates of the harvest in the various French vineyards. While the south of France – Provence, Languedoc-Roussillon, Corsica – has always led the way, it used to take a month before the starting gun was fired in the northernmost winegrowing areas. However, this year, the harvest for the AOC Alsace began on Monday, August 25, less than two weeks after the harvest in the Provençal vineyards. The precedent for such an early harvest in the Alsace region dates back to the heatwave of 2003.

In Maine-et-Loire, the harvest also began two weeks early – starting on August 18 in the Saumur region – and winegrowers are reporting in the regional press their difficulties in finding seasonal workers available from the end of August. Retirees and available students are being called in to help out.

According to winegrowers' memories, there were very early harvests in the past in August: the oldest mention the summer of 1893 in the Loire Valley, or August 1921 in Provence… Vines have always been affected by the climate. Physical geography researcher Valérie Bonnardot, who studied the harvest bans over a period of 130 years, between the 14th and 16th centuries, notes that the start of the harvest, generally at the end of September, could vary by a month, depending on weather conditions.

But what was once an exceptional phenomenon is now becoming the norm and is becoming more frequent due to global warming . The Ministry of Ecological Transition observed this by studying the evolution of the harvest date for a panel of French vineyards: Tavel, Châteauneuf-du-Pape, Saint-Émilion, Champagne, Alsace, etc. The study indicates that a trend towards earlier harvests began slowly from the end of the 1980s and accelerated in the 2010s.

"Today, in Champagne, the harvest takes place on average about two weeks earlier than twenty years ago. We observe that during most of the 20th century the harvest dates fluctuated around September 26, reaching on average September 15 from the 2010s. The earliness of the harvest is increasingly observed in 2011 (September 5), 2015 (September 2), 2017 (September 5), 2020 (September 3), 2022 (August 29) and 2023 (September 6)," notes the ministry.

Will this summer of 2025 mark an exceptional or lasting acceleration of the phenomenon? Time will tell. What is certain is that global warming is accelerating all stages of grape development. Budburst (the appearance of buds), which is occurring earlier and earlier in the spring, makes vines vulnerable to frost.

On average, flowering also begins two weeks earlier than it did forty years ago, and veraison up to 20 days earlier. This final stage before the harvest, during which the grapes are ripe and begin to accumulate sugars, now occurs in the heat of August. This is not without consequences for the composition of future wines, which may lose acidity, become sweeter, and see their alcohol content increase. All these changes are more pronounced during heatwaves.

This doesn't necessarily bode well for already sweet white wines like Alsatian Riesling or Gewurtz. In other regions, however, such as Corrèze and the Rhône, very good vintages are predicted after this year's harvests, thanks to grapes that are still acidic but high in sugar, which should offer beautiful aromatic concentrations.

While winegrowers are already banking on the quality of this early harvest, they hope that it will compensate for the quantity , as the grapes have remained small due to the drought.