This should prove to be a vintage year for British wine, thanks to the sunny weather at either end of the summer and the wetter middle period, experts have predicted.
They have also said that climate change is extending the growing season, further boosting the expansion of the industry.
Guy Barter, chief horticulturist at the Royal Horticultural Society, said growers will be looking to harvest their grapes quickly, before October’s rain and cold weather rots them.
“At one time, the growing season, which is defined as five days at 5C or more, has lengthened by about a month, so there’s that much more period of time for the grapes to grow and ripen,” Mr Barter said.
“They only flower in May so they haven’t got a lot of time to ripen before October.
“When I was young, the autumn would come in mid September and spring wouldn’t really come until mid April.
“Now, spring comes in early April, but the real lengthening of the growing season is in the autumn so that good weather can now be reasonably certain in the south right up into October.”
He added that a larger crop does not necessarily produce better wine.
“You’d think 2018, when it was really hot and droughty, would suit grapes.
“At Wisley, we had a yield of five tonnes of grapes, which was too much and the quality was not there because it was just too big and bulky a crop - the flavours diluted by the number of grapes.
“This year we’ve got a tonne and a half and they’re just the right level of acidity and sugar.”
Sparkling wine is a particular strength of British viticulture because grapes that grow in relatively cooler environments tend to be higher in acidity, which enables a better fizz.
This country still lacks the sun and warmth needed to produce quality reds, so most growers produce white wine, though there are vineyards as far north as Yorkshire which use south-facing slopes to get as much sun as possible.
Joe Fattorini, a wine writer and television presenter, said warm weather at the start of the summer was crucial to allow grapes to flower properly.
“Each vintage has its upsides and downsides - certainly the fabulous weather at the start helped the flowering.
“Grapes can be so susceptible to cold and heavy rain at that stage, but if it’s gone well then wet weather in the middle of the summer can be absolutely fine for them.”
He added: “It’s the sunny spell at the end that helps the skins and the pips really ripen.
“I do think this will turn out to be a good year.”
Growing grapes in Essex
In Essex, which is swiftly growing in fashion as a grape-producing region, producers have said they hope the wet July followed by warmer August could create a “sweet spot”.
The county experienced its wettest July since 2015 and the cloudiest since 2012.
The changing conditions are encouraging wine lovers to grow vines in their gardens.
Mr Barter said: “As well as commercial grapes, more and more people are growing grapes in their garden and if you’ve got a south-facing fence or a south-facing wall, then it’s well worth having a flutter.
“They’re one of the more interesting forms of soft fruits that can attract people’s attention.
“Possibly you would need a greenhouse for the best dessert grapes but if you fancy a bit of home wine making, it’s entirely feasible.”