The images of high-rise urban greenhouses like the one being planned in Sweden may be compelling, but according to many horticulturists, such plans are largely impractical. As horticulturist Cary Mitchell of Purdue University explains, “[t]he future of vertical farming…lies not in city skyscrapers, but rather in large warehouses located in the suburbs, where real estate and electricity are cheaper.”
Not only are vertical farms not likely to be urban greenhouses, they’re not likely to be “green” at all, but will rather glow pink from a mix of blue and red LED lights.
So why pink? As Michaeleen Doucleff reports, “Plant's photosynthesis machinery is tuned to absorb red and blue light most efficiently.” And by providing those wavelengths most essential to growth, vertical farmers can reduce their energy costs.