Thugs. Presenter Chris Collins has a soft spot for tough, often aggressive, plants like phormium and bamboo, which will take over a garden given the opportunity. In this episode he tames a north London garden under siege from such "thugs", meets a plantsman specialising in enormous plants and joins conservationists to investigate some of the plants which are in danger of dominating Britain's countryside.
Director Peter Leonard ; Series producer Kathy Myers www.bbc-co.uk/gardening