This seminar asks how ‘secret’ green spaces create collective urban possibilities as well as zones of exclusion. This talk will address some of my recent research and creation projects in the arguably liminal zones of postindustrial ecology and locked gardens. Through these projects I am working on the following questions: What roles might ‘secret’ urbanism, such as guerrilla gardens, play at a time when public space is increasingly claimed by neoliberal interest? How might such spaces be a means to understand a city’s history and morphology? When such secrets become public, what is lost, and what is gained?