Why on earth would anyone want to grow food on a roof? For lots of reasons. Urban rooftop agriculture can enable communities to positively affect their health, environment, and economy, while simultaneously promoting the occupation of underutilized space and strengthening the local food system. When applied at a neighborhood or city scale, rooftop agriculture has the potential to increase food security and decrease the urban heat island effect, particularly when coupled with other city planning and landscape architectural strategies. Benefits vary depending on the scale of production, but even very small applications can positively impact individuals and communities.
Health benefits of rooftop agriculture include those within the realms of social health and human health. The social health benefits consist of the provision of green space, the occupation of underutilized space, community building, and a strengthened local food system. Human benefits can include access to fresh, organic food, improved nutrition, the promotion of healthy eating habits, and the reconnection of people with their food.
The Environment can benefit through stormwater runoff mitigation, the utilization of vertical space, a reduction in fossil fuel use and air pollution (from decreased food transportation), and possibly even urban heat island effect reduction (when applied at a city-wide scale).
The Economy can benefit from by keeping money within the local economy. Urban rooftop agriculture can also create green jobs and attract consumers to the area, and building owners can additionally benefit by capitalizing upon underutilized space within their property. In Singapore, for example, building owners sometimes rent their rooftops to farmers and gardeners. Imagine if you could rent a community garden plot on the roof of your apartment building, just like you rent a parking space in the garage. One day this could become a building amenity that is expected by renters.
The multiple benefits of roof gardening are fascinating. Out of curiosity, do you also include wall gardening in this category? Why would someone grow food on a wall as opposed to a roof?
Interesting question. Growing food on a roof, up a wall, or inside several levels of a building are all considered to be types of “vertical agriculture.” This book focuses only on rooftop production, but recognizes that there are many different types of surfaces on which to grow food.
Edible walls are popular in university settings, or other slightly private places that experience a lot of foot traffic. These walls often emphasize demonstration over pure production, where visitors can walk by and harvest their own berries, for example. Green (or vegetated) walls, by contrast, are often located in the public right-of-way, particularly in Europe.