Current predictions of how plant species might respond to changing climates are often based on correlative models of climatic conditions and current distributions in natural ecosystems to determine their ‘realised niche’.  However, this approach may be a poor predictor of where plants can grow under future climates because their ‘fundamental niches’ may be greater if other ecological limitations are overcome. Cities and their urban plantings provide a wide network opportunity to study how plants function beyond their realized niche. Cities also provide a range of environmental conditions under which to study species responses, due to gradients in urbanisation, infrastructure configuration, rainfall, soil types, irrigation and management regimes.  Urban plantings therefore have significant potential to improve our ecological knowledge of how plant species: (i) cope with climates that are warmer and drier than their natural ’realised’ niche, (ii) physiologically respond to environmental extremes; and (iii) adjust or respond to these extremes over the long-term.  This Inspire ESA session will demonstrate how urban plantings can be used to test plant trait expression and plasticity in response to climates beyond their natural ‘realised niche’ and distributions and how ecological principles can be used to design functional urban plantings.  We hope to encourage researchers who currently work in natural ecosystems to consider how urban plantings could enhance their research into plant responses to a changing climate.