The ‘Compact City’ model of sustainable development relies almost exclusively on transport energy analysis to justify the raising of low residential densities by the insertion of higher density dwellings within them. Higher densities mean more people per hectare, which makes public transport more economically viable, which cuts down on car use, which saves transport energy. Suburbs are very popular, however - over 80% of the populations of the UK and the US would prefer to live in them - and they can't all be bulldozed or ‘densified’. Turning the Compact City model on its head frees us to ask what environmental advantages low densities might have. Most suburbs have abundant open land, and land can perform: grow food and fuel, collect and recycle water, modify harsh microclimates, save and generate energy. The ‘performative’ potential of the suburban landscape can transform it into a grown infrastructure contributing to the reduction of the overall environmental impact of a city region, justifying its relatively low densities.