At first, it is hard to believe your eyes. There, just behind the maple trees that line the driveway to Andy and Nichola Hill's magnificent country home, is the most picturesque vineyard imaginable: 100,000 vines soaking up the sun, sloping gently away towards the distant hills. It could be an idyllic scene in Bordeaux or Provence. Only we're in Sussex, a few miles west of Guildford, to be precise, which sounds rather less romantic than rural France.

In fact, the Hills' estate, Nyetimber, is just as lovely as the grandest of French chateaux. Barely seven years after their state-of-the-art winery produced its first batch of sparkling wine, the Hills are being feted as leaders of an exciting new pack of British wine growers who are taking on the French at their own game - and winning. 'Fantastic, isn't it?' says Andy as he tells you proudly that Nyetimber's 1996 Classic Cuvee was voted better than French champagne in a recent Which? blind taste test.

Nyetimber also cleaned up at the International Wine and Spirit Awards and the UK Vineyard Association's awards, with a total of six gold medals and four trophies this summer. Andy is bullish in the face of reports that the quality of British wine is likely to suffer because of the wet summer in contrast with last year's, which was when Nyetimber began to attract so much attention. He says: 'The vintages we are winning awards for now are 1994 and 1996, not 2003 - we won't be selling that until 2010. And the '94 and '96 vintages were produced in typical British weather. That's what we're geared up for. The weather affects the quantity, not the quality, of the wine we produce.'

I am sipping coffee with Andy and Nichola in their West Sussex kitchen. Normally, their housekeeper would be cooking lunch but she has a day off so Paul Bloxham, chef-proprietor of the much-applauded Cabinet in Hertfordshire, is driving down with a basket full of fresh produce, which he is planning to transform into a traditional Sunday lunch 'with a twist'. The guests are Andy and Nichola's friends Chris and Ingrid Tarrant, and Patti Boyd - famously married first to George Harrison and then to Eric Clapton - along with her boyfriend, Rod Weston.

Probably not all English winemakers have quite such rock'n'roll pals but Andy and Nichola Hill have not always been in viticulture. Before taking on Nyetimber, they spent more than 20 years in the music industry, starting off in the early Eighties with the creation of Bucks Fizz, who were put together by Nichola and produced by Andy, who also wrote all their songs. Andy has written and produced pop songs ever since, for people such as Celine Dion, Cher, Diana Ross, Craig David, Cliff Richard and Barry Manilow, and he has no plans to stop: his latest proteges are D-Side. Nichola, who was a choreographer and session singer, gave up work when she had Thomas, now 16, and twins George and Freddie, 11.

As we sit in the black and pink kitchen, Andy and Nichola bicker good-naturedly in the comfortable way that only a devoted couple can. He teases her for being a dreadful cook ('you should see the smoke that comes from the oven'). She makes fun of him for being a foodie.

'When I found Nyetimber three years ago, it was the house I wanted, not the winery,' says Andy. 'The vineyard just seemed to me like a liability.' He and Nichola had been living near Gatwick, but the airport and related road traffic had become unbearably busy. 'I couldn't stand the noise of the cars and planes. I wanted to live somewhere tranquil.'

Nyetimber was perfect. Nestling quietly in its own Sussex valley, it is a magnificent half-timbered manor, dating back to Saxon times. Mentioned in the Domesday Book, it was once the home of Anne of Cleves. There is a minstrel's gallery in the double-height drawing room and the most gorgeous, snug, panelled dining room.

There are numerous rambling barns and outhouses, and the gardens and two ornamental lakes are exquisite. Andy fell in love the moment he saw it - but not with the vineyard. 'Who in their right mind would want a vineyard and winery producing English sparkling wine?' he asks. 'As far as I knew, English wine was a joke.' He tried to persuade the owners to sell the house by itself but, having planted the vines themselves in 1988, they were adamant that the winery and the house should stay together.

Curious, Andy took himself off to Berry Brothers, the wine merchants, and asked them whether they'd heard of Nyetimber fizz. 'They couldn't praise it enough,' Andy recalls. He bought a bottle and was quite won over: 'I thought it was fantastic, and I was never much of a champagne man before then.' Nichola, on the other hand, has always drunk little else. She laughed in Andy's face when he told her he was thinking of buying an English brand but he persuaded her to do a blind tasting. She chose Nyetimber above Louis Roederer's Cristal.

That clinched it. They bought the estate in 2001 and moved in a year later. The idea of the time lag was to allow Andy to carry out essential repairs. 'But when we got here he'd done nothing, it was a pile of rubble!' shrieks Nichola, who has returned to the kitchen wearing pink and black cocktail dress and vertiginous heels. 'I described it as work in progress,' recalls Andy with a grin. Even now, the house is unfinished: boxes of books are stacked up on the minstrels' gallery waiting for shelves and the swimming pool is half-built. 'We'll get there,' says Andy optimistically. Nichola rolls her eyes: she'd much rather live in London - 'I'd like this place much better if it was in the middle of Hyde Park' - and claims she can only stand it at Nyetimber because she keeps 'an incey, wincey flat' in Chelsea, London, to which she escapes each week.

Andy shoos her away and takes us off to his studio at the top of the gardens, a stunning converted barn with a 12-foot high window through which he can gaze, while composing, across his lakes to the Sussex hills beyond. 'This was really why I bought the place,' he says, as we look at the dozen or so electric guitars lined up against the wall. 'I had an amazing studio in my old house, but I built it in the Eighties when it was the fashion to have studios which shut out the outside world. Mine had no daylight at all. In the end it felt like working down a coal mine. My face had a deathly grey pallor and I began having trouble writing. I needed some light.'

We wander into the winery next door to the studio, with its gleaming silver vats and stacked wooden crates of bottles ready for dispatch. Andy breathes in the smell of stale wine and squelches in the puddles of spilt blanc de blancs on the floor. 'My parents owned a pub, so I must be one of the few people in the world who likes the smell of beer- soaked carpets and wine-drenched floors. It's very evocative for me,' he says.

Staff are disgorging this year's vintage - removing the lees, or sediment, from the bottles in preparation for labelling. When the Hills took over, they kept on everyone who had been employed by Nyetimber's previous owners and brought in more master technicians from France and another English winery. 'We had to gear up the business to being a bit more commercial. We invested quite a bit in making it pay for itself. It had been a bit of an amateur enterprise,' Andy says. 'But the emphasis is still on quality and it always will be. It's boring otherwise. I want to produce something I can sit down and drink with my friends and know we're going to enjoy it.'

We jump into Andy's Land Rover and tour the vineyard. Surveying his immaculately kept vines, which produce 80 tons of grapes each year, Andy explains what makes Nyetimber sparkling wine special. Traditionally, because of our climate, English growers have specialised in German grape varieties, which can be hard on the discerning palate. However, like other newer English vineyards, particularly in the south, Nyetimber is planted with French grape varieties, such as chardonnay and pinot noir. It has virtually identical chalky soil to Champagne and uses the same technique as the wine growers there so the wine has a depth of flavour to rival champagne, for much less money. Nyetimber is already being sold at Waitrose, but the other big supermarket chains have been slow to pick up on it - and on similar labels such as Chapel Down in Kent and Ridgeview Estate in East Sussex, which are judged to be in the same league. Perhaps they might pull their socks up when they hear that Gordon Ramsay, Petrus, the Oxo Tower and Rick Stein, among others, have Nyetimber on their wine lists.

When we arrive back at the house, the scent of roasting beef and Yorkshire pudding, which Paul Bloxham plans to stuff with foie gras, is irresistible. Paul amazes Nichola and I by confiding that there is no need to cook Yorkshire puds at the last minute - 'just do them in advance and warm them through when you need them. They should stay risen all afternoon if you do them right. How else do you think restaurants manage to serve so many of them at the same time?' This is just as well because the guests are fashionably late. As we sit down at the table to eat, the talk is, not surprisingly, of old rockers: Rick (Parfitt), Ronnie (Wood) and Charlie (Watts) and their various states of health come up for discussion. Tales of friends with cancer turn the mood sombre, perhaps reflecting the rain that has begun to pour down outside.

Nichola shivers in her cocktail dress and Andy tells her to put on something sensible, like one of his sweaters. 'Don't give me sweaters!' she shrieks. Turning to the rest of the table she says. 'He tricked me, you know. When I first met him he was this young, handsome, drug-taking, hard-drinking, sexy musician. How was I to know he was going to turn into a boring old git who just wants to live in the country, making wine and wearing sweaters?' Everyone laughs. The mood lightens. Andy pours more fizz.

Nyetimber is available from Waitrose or Majestic; or direct from the vineyard (01798 813989, www.nyetimber-vineyard.com). Paul Bloxham is at the Cabinet, Reed, Hertfordshire (01763 848366, www.thecabinetatreed.co.uk)

· Win six bottles of award-winning Nyetimber wines worth over £120 Send a postcard with your name, address and telephone number by 27 September to OFM/Nyetimber, Freepost MID20916, Birmingham B26 3QQ