The designer overthrown? Welcome to the beautiful and dangerous world of self-seeding plants! A talk with pictures at St John's in Waterloo, then a walk round some of the public gardens looked after by Putting Down Roots, a gardening project for homeless people run by St Mungo's. We'll see the communities of plants that self seed, consider seed banks in the soil as security against vandalism and look at the parallels between plants and people that the language of gardening suggests: natives, aliens, invasive, naturalised. Some of our plants are benign, some poisonous, some are both!