Recently, I have become interested in the concept of urban rooftop gardening. This may seem odd because I don’t live in an urban environment, and indeed, where I live it is much more convenient to garden on the ground, which we do.
But I like to imagine a large apartment building in a city like New York City. The roof is planted with vegetables and herb borders. Maybe there are even a couple of fish tanks, and the fish’s water is recycled to water and feed the vegetables. Everyone in the building helps caretake the garden in exchange for a portion of the food produced. This is truly producing food locally. So why aren’t we doing this?
Green roofs have many benefits. The most important, besides producing food, is to mitigate the “heat island” effect of cities, which contributes to climate change. Conventional roofs reflect back sunlight, making urban areas 7 degrees warmer, on average, than surrounding areas. If all roofs in a city were “greened,” the temperature could be reduced as much as 12 degrees.
In addition, the green roofs provide a habitat for birds and insects such as bees. They capture pollutants and keep rainwater from running off roofs. They also extend the life of the roof and make the buildings more energy-efficient. What’s not to love?
Copenhagen has taken an important step by mandating green roofs in all new buildings as part of the city’s efforts to go carbon neutral. More cities should follow this example. Greening city roofs is a low-impact, relatively low cost solution with a lot of benefits and very few cons. It’s frustrating that it seems like we resist these simple ideas.