Eric Robson and his panel of experts visit Merseyside. Bunny Guinness, Pippa Greenwood and Bob Flowerdew answer the audience questions. This week the panelists offer advice on when to harvest sweet potatoes, what to grow in a semi-shaded patch, and how to tackle a nasty case of Pytophthora. They also suggest uses for homemade compost, ways to spruce up a messy alleyway, and methods for clearing an allotment of brambles. Bunny Guinness meets with Ed Bastow of Material Change to track where green waste goes after it's been taken to the tip. Produced by Dan Cocker Assistant Producer: Laurence Bassett A Somethin' Else production for BBC Radio 4.