The current situation stands as this, the UN estimates that our population will hit 9.6 billion in 2050, of which 70 percent are predicted to live in cities. This has caused The World Bank to estimate a need for 50 percent greater food production. Such statistics remind us that we need to radically re-think our idea of urban living before our world gets too hot, hungry and crowded. Rather than being solely concrete jungles, cities need to adapt to the pressures of today and become more agriculturally productive. Imagine a skyline where you look up and see green instead of grey. Urban farming and in particular rooftop farming is a good way of doing this.
For NYC it’s a match made in heaven; there are an estimated 14,000 acres of unused sunny rooftop spaces, giving the city great urban farming potential. Plants on these rooftops would help purify the city air and add oxygen to the atmosphere through photosynthesis. Already, people are developing their rooftops, but often only for leisure patios; these tend to use dark materials, like wood or tar, that further absorb NYC’s heat, exacerbating the Urban Heat Island effect (the tendency for cities to be hotter than their surrounding rural or suburban areas). On the contrary, green roofs would help keep NYC cooler.
Furthermore, by growing produce in the city food miles are cut and the end product is fresher and more nutritious. No more buying apples from China. The planes, ships, trains and trucks required to get your food from A to B are more or less cut from the equation; food grown on NYC’s rooftops is never far from its point of consumption. Consequently, carbon emissions from transport are significantly reduced and you can eat well knowing that your food hasn’t been sat in a refrigerated truck for weeks. (Nb. Fewer food miles does not always indicate eco friendliness, as if the farms use a lot of fertilizers or tractors it might negate any said benefits – yet here this is not the case)
Another benefit of rooftop farms is their ability to reconnect New Yorkers with their food. Few know or understand where their food comes from, or how it is grown, or who harvests it. This might seem like common sense to most people, but in reality white fluffy bread rolls are a far cry from the cereal grains they derive from. These green leafy roofs can provide an education for the average New Yorker.
This brings us onto our case studies; Brooklyn Grange began in 2010, founded by Ben Flanner, Anastasia Plakias and Gwen Schantz. It is the world’s largest rooftop soil farm, occupying a total of 2.5 acres over two different locations in Brooklyn and Queens. It took six days and 3,000 lbs worth of craning soil onto the roof of a seven-storey building in Brooklyn to complete the first farm. Now, each year the output from both farms is more than 50,000 lbs of organically grown produce; in their first year the company broke even. Since then Brooklyn Grange has gone from strength to strength, creating a commercial apiary and launching a variety of educational workshops and programmes. Check out the time lapses and photographs of the farm below, it really is a surreal setting, who would have guessed such activities were occurring above us?
The next case to look at is Gotham Greens, a company with a slightly more new-fangled and techy approach to rooftop farming. Gone are the romantic ideas of hoeing the land and getting mucky and muddy in the process. In is hydroponics; Gotham Greens grows its vegetables and herbs in renewable energy powered hydroponic greenhouses; these don’t require soil, only a nutrient rich solution that is delivered to the plants by irrigation. The water used is recycled and recirculates, thereby preventing waste. Incredibly, only 700 gallons are used per day, which is a tenth of what conventional farming uses; thereby giving hydroponics the title of the most water efficient form of agriculture in the world.
The greenhouses are strictly climate controlled, enabling them to grow vegetables all year round and maintain the perfect conditions for good quality growth. Unsurprisingly, the resulting yields are strong, generating 20-30 times more product per acre than conventional field production and thereby avoiding the need to use more of the earth’s limited resources for traditional farming.
And finally, if you are lucky enough to live in the trendy Brooklyn area, Gotham greens’ has partnered up with its biggest customer - Wholefoods - in Gowanus. They have added a 20,000 square foot greenhouse to the rooftop of the grocery chain’s new store, enabling their veg to be harvested and brought down to the shop floor in less than twenty minutes, undoubtedly making it the freshest produce in town.