Introduction: The world’s cities are becoming increasingly congested and polluted (Blanco et al., 2009). Urban green spaces provide a wide range of ecosystem services that could help combat many urban ills and improve life for city dwellers—especially their health. Such green spaces are diverse: they vary in size, vegetation cover, species richness, environmental quality, proximity to public transport, facilities, and services (Dahmann, Wolch, Joassart-Marcelli, Reynolds, & Jerret, 2010; Fuller and Gaston, 2009; Sister et al., 2010). Public green spaces include parks and reserves, sporting fields, riparian areas like stream and river banks, greenways and trails, community gardens, street trees, and nature conservation areas, as well as less conventional spaces such as green walls, green alleyways, and cemeteries (Roy, Byrne, & Pickering, 2012). Private green spaces include private backyards, communal grounds of apartment buildings, and corporate campuses.