Rod Leeds, who lives at Preston St Mary, and Dr Christopher Grey-Wilson won a gold medal and the RHS President's Award for the best garden in the Chelsea pavilion.

Mr Leeds and wife Jane helped build the alpine garden which was designed by Dr Grey-Wilson.

The question time will be one of the features of the third Great Garden Event, in the grounds of Preston Hall, on Saturday, June 14.

Mr Leeds said: "With Christopher we have been building gardens at Chelsea and sometimes Hampton Court for about ten years. So far, we have always won gold."

Friends of Preston St Mary Church chairman Ralph Crapnell said: "We hope many people will turn up for advice and bring along a question or even specimen plants to test the panel," said Mr Crapnell.

The event regularly attracts more than 1,000 people and includes trade stands, music and refreshments, auctions, raffles, a family quiz and guided tour.

Gates are open 11am-5pm, with question time at noon. Entry is £3.

All proceeds go to fund church repairs.