Introducing rooftop vegetable gardens for sustainable cities

Producing edible biomass on rooftops is a growing worldwide demand of large urban areas. Scientists Grard et al. achieved for the first time a quantitative assessment of several ecosystem services delivered by a productive green roof based on urban wastes. They show that low-tech productive rooftops, particularly easy to manage, allow the recycling of organic wastes and the production of vegetables by using rainwater but no chemical fertilizer.