NOT many sculptors expect to be put on bird poo patrol.

But part of the ethos of Asthall Manor’s biennial On Form exhibition – the only exhibition in the UK dedicated to stone sculpture – is that the artists help run the show, from setting up to front desk duties.

Checking exhibits for bird droppings is one of the less glamourous tasks, but one that helps to keep the exhibition running smoothly and ensures that visitors see the exhibits in optimum condition.

This is particularly important given Asthall’s policy of encouraging visitors to touch the exhibits, so that they can appreciate their different shapes, textures and temperatures, and perhaps be surprised at the sheer variety of stones and how they interact with each other and the landscape.

One of Asthall Manor’s strengths is that it thrives on the unexpected. On Form is a remarkable synthesis of old and new, with contemporary stone sculptures set against the backdrop of a traditional 17th century Cotswold manor that was once home to the Mitford family.

The gardens play their part, too. They were transformed in 1998 by Julian and Isabel Bannerman, and again reflect the coming together of contrasting elements, with a fusion of formality and spontaneity flowing down to the River Windrush. Its hillocks, arbours, nooks and crannies make perfect settings for the stone sculptures.

On Form was conceived in 2002 by the manor’s current owner, Rosie Pearson, inspired by the astonished reaction of locals to the pumpkin-like finials she had commissioned from sculptor Anthony Turner for the entrance gateposts.

The first exhibition had about 50 sculptures and attracted 1,000 visitors; this year there are more than 200 sculptures and, based on the 2012 attendance figures, Rosie is expecting at least 7,000 visitors during the month-long show, which runs until Monday, July 6.

She and curator Anna Greenacre have everything worked out with military precision months in advance, deciding exactly where to place each exhibit.

“Anna and I spent weeks walking round the garden with our file of all the pictures of the sculptures,” Rosie said. “When you’ve got a whole exhibition, every inch matters, so it’s really important that everything is in exactly the right position.

"It’s such fun to do. I like it, because it’s a puzzle, but there isn’t a right or wrong answer. I love things that don’t have right or wrong answers. There are infinite different ways you can do it.”

Sometimes sculptures don’t look right in their planned positions, but for Rosie this experimentation is all part of the fun, with last-minute changes made when the pieces have arrived to show them off at their best.

One of the largest exhibits this year is The Madonna and Child by Matthew Spender.

“We wanted this to be in the church but then realised it was too big to get there, so we’ve got it looking at the church instead,” Rosie said.

This year’s artists were selected from over 100 hopeful applicants, which Rosie had to whittle down to 30.

“It was really hard,” she added. “And it’s not just to do with your favourite ones, it’s also ones that are going to be an interesting mix.”

She always aims for a blend of as many different styles, genres and stones as possible.

“Sometimes you suddenly realise you’ve got too much white marble or too many heads.

“We’re a bit more figurative this year, so we have five actual bodies or torsos but so many other pieces are based on the human form. And what I love is that sometimes you can’t quite tell if something is abstract or figurative, but it reminds you of something.”

There are practical considerations, too.

“The ones who have been before make installation easier, because they know how to do it. They know the garden, and you don’t have to give them so much attention. But we want new ones as well, to keep it fresh.”

Witney Gazette: Matthew Spender’s Madonna and Child in front of the manor house

One artist who is familiar with showing at On Form is Aly Brown, who is making her second appearance at Asthall in this year’s show.

“It’s just brilliant,” she says. “It’s so lovely to meet fellow sculptors and combine our work together, and it’s all so different. Normally we all work on our own at home, then we come here and it’s a total community.

“Rosie does a lunch in March when we all get to know each other, then everybody helps each other set up. So it’s great, a real fellowship of artists. It’s so amazing to look at bits of stone that are all so different, and the setting here just lends itself beautifully.”

Aly began stone carving 16 years ago, specialising in abstract female forms, mainly in Portland stone, marble and alabaster.

“It was like a duck to water,” she says. “There’s something about stone, the sensuality of it, the feel of it. It’s so wonderful here that everybody can go and touch the stones. And all the people that come here love art. There’s always somewhere to look and there’s always something placed beautifully.”

The sculpture rising from the pool is, I now discover, one of Aly’s pieces, and she is thrilled with its placing.

“When I saw the swimming pool, I just wanted to have a piece in that. They made it last year into a natural pool, as opposed to a swimming pool, and I just felt a piece would go there so well. It was lovely putting it in there.”

As in previous years, all works are for sale, and can be seen in Asthall Manor’s grounds and ballroom, and in the adjacent St Nicholas Church.

  • On Form runs until July 6. It is open from Wednesday to Sunday, between noon and 6pm each day. Admission is £7.50 for adults, £6 for over-60s, students and under-18s and free for children under 12.
  •  Asthall Manor is off the A40 at the Asthall Barrow roundabout. For more details, see onformsculpture.co.uk or call 01993 824319