Up on the roof: Considerations for food production on rooftops

Abstract

Green roofs are increasingly common. Planting on a rooftop is a way to insulate buildings, reduce stormwater flows, and potentially provide space for birds, bees and people to congregate. Engineered media has been developed that allow for planting on green roofs. Green roofs have also been recognized as a place to grow food. Rooftop agriculture can be as varied as the many types of in-ground and greenhouse agriculture that are more familiar to most people. For example, row farming, container gardening, and hydroponics are all possible under open sky as well as in greenhouses. Each type of cultivation can be carried out on a roof surface as well as on the ground. Different forms of cultivation come with their own set of advantages and disadvantages. Greenhouse and hydroponic production are both much more highly managed and controlled systems, and the potential differences between rooftop and ground level production are therefore likely to be smaller. Rooftop agriculture under an open sky, either as row farming or container production is likely to be more different than in-ground operations of this type than either greenhouse or hydroponic operations because they are more exposed to the novel environment of the rooftop. Our discussion of rooftop agriculture will be focusing on the row farming and container gardening operations that are open to the sky. These types of rooftop agriculture may use pre existing green roof technology.