The curtain is not yet ready to drop, but it would seem the final act is already under way for Garsington Opera.

After more than 20 years of spellbinding singing in its majestic setting, with planning battles and villagers' protests occasionally adding a touch of real-life drama, the opera is looking for a new home.

Those who have followed the development of one of Oxfordshire's cultural showpieces will know that the voices of doom have sounded before, as ombudsmen and council planners made their unwanted entrances.

But opera lovers simply clung to their picnic baskets and kept faith in the Ingrams family, who first opened up their historic manor home for a festival of opera in 1989.

This time, however, there will be no last gasp or dramatic twists. The consolation for the hundreds who flock to the village in Oxfordshire every summer is that it will be a planned and dignified ending.

This summer, opera lovers can look forward to performances of Mozart's Cosi Fan Tutte and Stravinsky's The Rake's Progress, as well as an exclusive first performance in Britain of Vivaldi's 300-year-old opera L'incoronazione di Dario.

Plans for next year's 20th anniversary season are in place, with casting already under way for the 2010 season. But it has now been announced that the opera is seeking a new home for the 2011 season and thereafter.

None of this has anything to do with a reprise of discontent from local residents.

Fittingly, it all comes down to the death of the hero of Garsington Opera (at least in the eyes of music lovers) - Leonard Ingrams, the merchant banker who loved opera so much that he decided to give up his garden to it every summer.

It was never likely that Garsington Opera would long survive Mr Ingrams, who died three years ago, aged 63.

His own place in musical history, however, is surely secure as Oxfordshire's great accidental impresario.

For the festival all came about because of his decision to give a hand to two local campaigns: one to help The Oxford Playhouse reopen, the other to stop a new town being built down the road at Stone Bassett.

In a way, things may seem to have come full circle, with Garsington residents now preparing to fight city council-backed plans for thousands of homes in an extension of Oxford, while plans for a new town near Weston-on-the-Green have found their way on to a Government shortlist.

A production of The Marriage of Figaro over two nights managed to raise £15,000 for the campaign funds. The following year he decided to do a fundraiser for the Bodleian Library.

He and his wife, Rosalind, had, in 1982, bought the manor house at Garsington, once the home of Philip and Lady Ottoline Morrell, and a favourite place of the Bloomsbury Group.

The Ingrams quickly came to the view that if they were to have an opera, it should be done on a professional basis, with Mr Ingrams applying his considerable acumen as chairman of a board of directors, with a team of advisers that included author John Mortimer.

What they created is best summed up by Chris Purves, the accomplished Summertown-based opera singer who will appear as Nick Shadow in The Rake's Progress this season, having appeared in the 1995 production of Haydn's La Fedelta Premiata and Rossini's La Gazza Ladra in 2002.

"I was immediately struck by the beauty of the house and the most wonderful gardens, he said. "I think if you are staging an opera or any theatrical extravaganza outside the theatre, then Garsington is the most beautiful setting that you could imagine."

When the old theatre at Glyndebourne was demolished in 1993, Ingrams acquired its wooden panelling to use for a restaurant at Garsington. The banked rows of seats were protected by a canvas awning, and the terrace of the walled garden proved a perfect setting.

For Purves the magic stems from the combination of intimacy and the chance for audiences to lose themselves in formal flower gardens, with ancient yew hedges, Italian statues and sweeping views across southern Oxfordshire, once enjoyed by the likes of Virginia Woolf, DH Lawrence, WB Yates, Siegfried Sassoon and TS Eliot.

Like other performers, Purves, a former member of the rock band Harvey and the Wallbangers, has always appreciated the willingness of the Ingrams to take risks, staging neglected works of composers such as Haydn and Rossini and more recently Russian and Czech composers.

Then there was always the cheery sight of Mr Ingrams living out his dream.

"He was there every night - always there at rehearsals. You really have to pay homage to the passion and lunacy of the Ingrams, who allowed all these people into their home for a month every year."

Bedrooms in the house served as dressing rooms for performers. The house was used for receptions and post-performance parties. Even the kitchen was taken over.

"All this combined with brickbats from the local community. But he just got on with it. And this was a man who held down a very important position in the banking world."

But Rosalind Ingrams says watching the operas taking shape more than compensated for any inconvenience.

She said: "For me to watch the operas develop first in rehearsals in London and then arriving in my home at Garsington has been a great joy. We will have had 21 opera seasons here at Garsington - 16 during Leonard's life.

"But as a family we feel the time has come for new horizons for the opera company - and we wish them well."

Graham Greene, chairman of the board of directors of Garsington Opera, said: "After nearly a quarter of a century I think it is understandable that the family might want their garden back."

He believes that Mrs Ingrams has good reason for pride in both the high standard of the work and in the platform it gave to young British talent.

Mr Greene says the Garsington Opera Education Programme is helping to introduce opera to students at local schools, who take part in a range of activities such as composing, singing and mime. Students are also given the opportunity to see the opera they are studying.

This in turn has led to the formation of the Garsington Youth Opera Group, which started with a group of 20 students from Wheatley Park School, who performed their new work Ghosts in the Stones at Oxford Town Hall in February.

A community opera, which will be created from workshops involving Oxfordshire groups, which may also involve detainees from Campsfield House, is being planned for next year.

Mr Greene said: "The education programme has been terrific. I believe that in years to come, major young figures could emerge on to the opera scene as a result of this - someone who was first inspired to take an interest in opera because of what was put on for them at their local school."

He remains confident that a new home will be found.

"We would like it to be in the same catchment area and a similar distance from London. We would be looking to build an auditorium of a similar size. There are a lot of lovely houses about. We are hearing many suggestions, but no landowner has come forward yet."

And what of the villagers being left behind?

Geoff Russell, clerk of Garsington Parish Council, said: "It seems the problems always arose when planning applications were coming forward about some aspect of the opera, such as the number of evenings they were allowed to perform. But in the five years I've been clerk, it really has not come up as a major item. It is certainly not a hot topic here any more.

"I think a lot of people have been pleased to have Garsington Opera on their doorstep. Many people are going to miss it."

It is certainly starting to look like the dignified and harmonious ending that this famous old manor house deserves.