Heat putting winemakers in 'uncharted territory'
BBCWinemakers have said the sustained period of hot dry weather has left them in "uncharted territory."
Sam Lindo from Camel Valley, near Bodmin, said he may not be able to match the flavours of the company's normal crisp wines because the heat had made the grapes riper and more flavoursome.
Alina Stankus, co-owner of Venn Valley Vineyard, near Barnstaple, said there were signs of heat stress in her vines.
Without rain, the grapes would be smaller and not as good as they could be, she added.
Lindo, said: "This hot dry weather is very good, but for us it's very much uncharted territory."
He said Camel Valley made "really good wines that are slender, crisp, light in flavour, and this sunshine is going to be new territory".
"We're going to have more flavour, we're not sure what's going to happen to the acidity, it's very much unknown," he added.
Camel Valley has 24,000 vines which produce on average 150,000 bottles of wine a year.
Lindo said the weight of the grapes this year may be slightly lower because of the lack of rain.
"The grapes have less juice in them, so although you have the same number of bunches you will get less juice out of them," he added.
Drought was declared in Devon, Cornwall and the Isles of Scilly in July and the Met Office said extreme weather was becoming the new normal for the UK.
Lindo said with hotter drier summers predicted, change would be necessary.
He said: "Everybody in the world has currently got the wrong variety of vines in the ground that they will need for 20 years time."
He said vineyards in Bordeaux and the Champagne region were already replacing vines with varieties which could manage the heat and the same would have to happen in Devon and Cornwall.
Lindo said: "Luckily for us it is well chartered territory, we only have to look further south to see what we need to do next.
"The future is already here, it's somewhere else."
Venn Valley Vineyard, just outside Barnstaple, produces about 5,000 bottles of wine a year.
Alina Stankus, who owns the vineyard with her husband, said: "The leaves will turn sunlight into carbohydrates for the grapes, but those grapes need to swell with water."
Without rain she said the grapes would be smaller and not as good as they could be.
She said seyval blanc vines were the backbone of the vineyard but because of the heat they were over-cropping.
Stankus said she was having to carry out a green harvest, which meant taking off any bunches which did not stand a chance of ripening so they did not overstress the vine.
She said the pinot noir vines were starting to show signs of heat stress with leaves turning yellow very early in the season.
