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From high grass to high rises, this is the future of farming, with layers of growing beds stacked one on top of the other. NPR's Joel Rose visited one company in the Newark area that's making a big bet on vertical farming.
JOEL ROSE, BYLINE: From the outside, AeroFarms headquarters looks like any other rundown building in downtown Newark, N.J. There used to be a store and more recently a nightclub. Now it's a test farm.
DAVID ROSENBERG: My favorite is the mustard green. That's called a Ruby Streak, which is this leaf right here. My second favorite is cress - watercress, which is this guy right here.
ROSE: AeroFarms CEO David Rosenberg samples some of his company's greens which come in dozens of shades of green and purple. They grow in long, narrow beds stacked seven layers high, more than 30 feet up in the air. They're all under intense LED grow lights while their roots are bathed in a nutrient-rich mist.
ROSENBERG: The plants are really getting a white-glove lifestyle experience. They have people catering to their every need.
ROSE: Rosenberg says AeroFarms can control the light, temperature and nutrition these plants receive. The company plans to apply what it learns here at a big, new $39 million facility elsewhere in Newark. They'll join a growing list of working vertical farms in Asia, Europe and the U.S. The idea was first popularized a decade ago by Dickson Despommier, the author of a book called "The Vertical Farm: Feeding The World In The 21st Century."
DICKSON DESPOMMIER: The best reason for doing this, of course, is to supply fresh produce for people who live right next door to where you farm it. And the less impact on the land, the better.
ROSE: Despommier says vertical farming uses less energy transporting food to market while also requiring less water and pesticides than traditional agriculture. But skeptics say there's one glaring problem.
TED CAPLOW: The fact that plants need sunlight to grow has not changed.
ROSE: Ted Caplow is an entrepreneur and cofounder of a company called Bright Farms. It's also focused on growing leafy greens indoors but using the natural light of the sun. Caplow says vertical farmers are turning their backs on a free source of energy that plants have been using for millions of years.
CAPLOW: If you end up using more energy to light the plants, you know, in the Northeast than it would've cost to truck them across the country, then at least on an energy standpoint, you know, you're not coming out ahead.
ROSE: Vertical farmers counter that they can get their crops to grow faster than farmers who depend on the sun and that LED bulbs are getting more efficient all the time. But vertical farmers still face some other big questions too, like can they control pests and can they afford enough workers to harvest the crops? Stan Cox is a research scientist at The Land Institute, a nonprofit organization in Kansas devoted to sustainable agriculture. So far, Cox says, vertical farms tend to specialize in only a few crops.
STAN COX: It's always leafy greens. And the reason is that if you try to grow grains or fruits or vegetables like beans, tomatoes, potatoes indoors, out of the sunlight, the energy requirements for lighting become impossible.
ROSE: It also helps that baby kale and microgreens fetch top dollar at high-end grocery stores and restaurants. But AeroFarms' CEO David Rosenberg insists his company wants to feed more than just foodies across the Hudson River in New York City.
ROSENBERG: We set out to build AeroFarms, not to build one farm, not to build a farm for just the rich, but to really change the way we source our food for humanity.
ROSE: AeroFarms hopes to bring its first crops to market this fall. Joel Rose, NPR News, Newark, N.J.