From roof to table – urban food has reached new heights. Soaring prices and concerns about chemical-laden fruits and vegetables increasingly drive us to grow our own healthy food close to home. In cities, however, vanishing ground space and contaminated soils spur farmers, activists, and restaurateurs to look to the skyline for a solution. The hunger for local food has reached new heights, and rooftops can provide the space that cities need to bring fresh, organic produce to tables across...