Eric Robson and the team are at the Edinburgh Festival. Matthew Wilson, Bunny Guinness and Bob Flowerdew answer questions from an audience of local gardeners and festival goers. The panellists explain why tomatoes are prone to splitting, ponder over a failing rhubarb crop, and suggest plants for a Japanese garden. Eric Robson goes in search of the oldest floral clock in the world, and we answer correspondence from gardeners in Vancouver. Assistant Producer: Hester Cant Producer: Hannah Newton A Somethin' Else production for BBC Radio 4.