Eric Robson and the panel are in Liverpool. Bunny Guinness, Pippa Greenwood and Bob Flowerdew answer this week's questions. The panellists offer advice to a man with an 8ft cactus growing in his greenhouse, diagnose an ailing Cosmos crop and debate the best way to rid an allotment of ants. Questioners also grill them on baking apple trees, mare's tail, therapeutic plants and how best to grow okra in the UK. Matt Biggs visits Wanstead Flats in East London to meet garden designer Jonathan Snow and discuss the effects of fire on plants. A Somethin' Else production for BBC Radio 4.