No sunlight, no soil, no problem: Vertical farms take growing indoors

A New Jersey company is building the world's largest vertical farm inside an old steel mill, where it says it can grow millions of pounds of plants indoors, without the use of sunlight or soil. It's part of a trend to use tech to bring produce to dense urban areas.

New Jersey company seeks to build world's largest vertical farm inside old steel mill near the airport

Plants are grown inside a vertical farm facility in Newark, N.J., using a technique called aeroponics. (Steven D'Souza/CBC News)

Inside a windowless warehouse once used for paintball, with planes heading to nearby Newark airport overhead, an industrial park in New Jersey seems an unlikely place to find fresh locally grown produce.

With LED lights standing in for the sun, and cloth replacing soil, the plants grown at AeroFarms are not your typical greens.

"This is fully controlled agriculture and allows us to understand plant biology in ways that, as humans, we've never achieved," said AeroFarms CEO and co-founder David Rosenberg, standing in front of rows of kale, arugula, lettuce and other leafy greens.

This is a vertical farm — a facility that looks like it jumped off the page of a science-fiction novel instead of an agriculture textbook.

Here seeds are woven into a mesh cloth made of recycled materials. Trays of plants are stacked one on top of the other in long rows. LED lamps provide the light, while water and nutrients are sprayed in a mist to the roots as they dangle below — a process called aeroponics. 

"We give the plants what they want, when they want it, how they want it," Rosenberg said. 

World's largest vertical farm

The company is currently building what's been described as the world's largest industrial vertical farm, with food grown 12 levels high inside a 70,000-square-foot space, which the company says will produce two million pounds of food a year. It's set to open next year.

An AeroFarms' worker waters seeds freshly planted in a special cloth used to grow the plants. In vertical farming, the cloth replaces traditional soil and LED lights replace sunlight. (CBC News)

The pitch is enticing: locally grown food in any climate, year-round. In AeroFarms' case, they say they use 95 per cent less water, no pesticides and don't produce any of the waste that comes with industrial agriculture.

"We can take the exact same seeds that are out in the field that may take 30 to 45 days to grow, [and] we can grow it in 12 to 16 days by creating the perfect environment," said Marc Oshima, AeroFarms' chief marketing officer.

Problems with power

Indoor farming isn't a new concept. Farms across Canada are attempting similar concepts, trying to extend growing seasons and bringing fresher produce to colder climates.

But critics like Bruce Bugbee, a professor of crop physiology at Utah State University, say using artificial light to replace sunlight is still the biggest problem.

"I know how much electricity goes into the electric lights," he said, adding the cost doesn't include carbon emissions created from generating the power.

Then there's the problem of the light quality.

"To me, sunlight is still the gold standard for nutritional quality and they're aspiring to get it as good as the crops grown in sunlight," Bugbee said.

Big-ticket investors

Rosenberg says the company is using energy-efficient lighting and only grows the most cost-effective vegetables, focusing on micro-greens, instead of other vegetables like tomatoes, cucumbers or other larger produce.

Their efforts have won the support of big-name investors, like Goldman Sachs and Prudential, which have provided funding for the more than $30 million US project. One estimate projects that the vertical farming industry will grow to be worth as much as $6 billion US by 2022.

Plant roots are exposed during the vertical-farming process and are fed by a nutrient-dense mist sprayed directly on them. (CBC News)

With computer models, data points and mechanical engineers working beside plant scientists and crop physiologists, Oshima says the operation is less farm, more tech startup.

"We like to think of ourselves as the Apple of farming, so the growing towers are really the hardware, the growing recipes for each of the variety is really the software."

A matter of taste

Another knock against indoor and vertical farms is the question of taste. Can plants grown in unnatural environments replicate the taste and texture of outdoor- and soil-grown plants? 

To answer that, the company invited Marion Nestle — a professor of nutrition, food studies and public health at New York University — to tour their facility. Nestle was a skeptic.

"I rolled my eyes," she said, describing the initial invitation. "Why are we doing this when you can grow vegetables really beautifully in soil? What's the problem all of this technology is trying to solve?" 

AeroFarms says it treats its plants with specific types of light, which allows for more efficient photosynthesis. But critics say the excessive use of electricity makes the operation less green than it appears. (Steven D'Souza/CBC News)

But Nestle says she's now a convert, after tasting samples of the produce AeroFarms sells to local grocery stores, making it available to nearby schools and the community.

"They taste a lot better than the microgreens we get in New York that have sometimes been on the road for a week."

Whether AeroFarms' crops are as nutritious as traditional produce, Nestle can't say; the nutrients the company feeds its plants is a closely kept secret.

While AeroFarms pitches its methods as a way to disrupt traditional farming, save water and provide access to fresh produce in urban areas underserved by grocery stores, Bugbee says vertical farming — and the more expensive produce it grows — won't solve the world's food problems.

"It will provide terrific food for people that can afford it, but they shouldn't be saying they'll save the planet." 


  • An earlier version of this story said incorrectly that the new farm is in a two-million-square-foot space. In fact, the farm occupies a 70,000-square-foot space.
    Jan 03, 2017 8:51 AM ET


Steven D'Souza

Senior Reporter

Steven D'Souza is a Senior Reporter based in Toronto. Previously he was CBC's correspondent in New York covering two U.S. Presidential campaigns and travelling around the U.S. covering everything from protests to natural disasters to mass shootings. He won a Canadian Screen Award for coverage of the protests around the death of George Floyd. He's reported internationally from Rome, Israel and Brazil.


To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.

Become a CBC Member

Join the conversation  Create account

Already have an account?