Commonstudio's Global Urbarium is an evolving, multi-city celebration of spontaneous urban vegetation. The project employs the collective power of smartphone-empowered citizen science to reframe the conversation (and challenge negative stereotypes) surrounding "weeds" in cities. Inspired by Emerson's assertion that "A weed is a plant whose virtues have not yet been discovered", we believe that touching, identifying and celebrating the latent beauty of these urban ecologies may be a first step toward discovering those virtues.