September so far has been unusually hot in the Perigord and the winemakers are crossing their fingers that the sunshine lasts through the rest of the month, which should mean an excellent vintage this year. 

The cold spring and rains in June and early July had worried them, but while the harvest will be late, it should be very good indeed. The one great fear is the storms that usually come with the equinox around September 21. 

My Green friends are also worrying, because more and more winemakers in the region are going bio and avoiding pesticides and chemical treatments. But if we get heavy rains later this month and not enough wind and sun to dry the grapes, they fear that an outbreak mildew of mildew could provoke an anti-bio backlash. And while sulphur dust in limited quantities is approved for organic farmers, they prefer to use something more bio. 

Some are experimenting with diluted milk as a preventive and others are using a solution of water and garlic. Put one whole bulb of garlic in a litre of water with a few drops of liquid soap for a day, then strain it and dilute in with ten times as much water and spray. It works in our vegetable garden.

According to a study published by the journal Proceedings of the National Academy of Sciences in conjunction with Conservation International, global warming could have a perilous impact on the vineyards of the Dordogne.

With the world getting warmer, traditional wine-growing regions including (but not limited to) the Dordogne could see a significant fall in production over the next forty years, with Conservation International forecasting a two-thirds drop in output.

The hot dry summers so typical of Aquitaine are not just attractive to the legions of tourists who journey to southwest France each year – they are crucial to the region’s vineyards, who rely on the sun to do its job plumping the grapes that will become some of the best-known wines in the world.

The study examined the potential effects of two different temperature increases on nine of the world’s greatest wine-growing regions – a ‘moderate’ 2.5˚C rise, and a more dramatic ‘worst-case’ 4.7˚C increase. Seventeen climate models were used in the course of the study.

Bordeaux, Rhone, and Tuscany were hardest hit by the researchers’ models, and showed an 85 percent drop in production by 2050.

“The fact is that climate change will lead to a huge shakeup in the geographic distribution of wine production,” said study author Lee Hannah. “We expected to see significant shifts, but we didn't expect to see shifts like these.

“It will be harder and harder to grow those varieties that are currently growing in places in Europe,” Hannah added. “It doesn't necessarily mean that [grapes] can't be grown there, but it will require irrigation and special inputs to make it work, and that will make it more and more expensive.”