Vertical farming in Denver: Ullr's Garden is trying to save the world

2022-11-28 13:51:03 By : Ms. Erica Wang

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Leafy vegetables at Ullr’s Garden appear black under LED lights due to most plants’ total absorption of blue and red-colored wavelengths. Butterhead lettuce varieties are sold from Ullr’s with their roots still attached. (Olivia Sun, The Colorado Sun via Report for America) Led Grow Light Bulb

Vertical farming in Denver: Ullr's Garden is trying to save the world

The lettuce is blooming nicely on the rollaway walls. 

According to the farmer’s iPad, the calibrated nutrients are flowing smoothly and accurately through the tubes. 

It’s 30 degrees outside, but there’s a tantalizing garden of tangy, restaurant-ready produce inside this cozy, pristine shipping container. 

Somewhere behind and among the pawn shops and the gas stations and the used tire traders and the body shops along South Broadway, on a former used car lot on Acoma Street, a couple of snazzy high-tech containers are parked to start an urban farming revolution. 

Ullr’s Garden, launched a few months ago by a couple of brothers who want to save the world and sell some sustainable arugula, is growing the equivalent of a 10-acre farm on a dusty 7,500-square-foot lot. The lettuce and arugula and basil and romaine grow horizontally, while hanging from moveable walls packed inside the climate-controlled trailers. The farmers sit at a folding table in the nearby shed and plot their next expansion: stackable farm containers.

Nick Millisor, one of the brothers behind Ullr’s Garden, still can’t believe they’re doing what they’re doing. 

“We are growing local produce, in the middle of Denver, on an old used car lot, the kind you used to roll your car windows up when you drove by,” Millisor laughs. 

Ullr’s Garden currently consists of two shipping containers of hydroponic farms in South Denver. Each “vertical farm” can grow the same amount of produce as 5 acres of farmland. (Olivia Sun, The Colorado Sun via Report for America)

And their stuff tastes great. The emerald green basil snaps with a hint of licorice. The arugula is laced with a wild mustard flavor. The butter lettuce, sold with root ball intact, has an earthy flavor belying the fact the growing walls are purposefully insulated from any local dirt. 

One trailer with 365 days of optimal growing conditions can produce the equivalent of a 5-acre seasonal farm, Nick and Luke Millisor say. Employing a closed loop for the water and nutrients, each trailer uses up only five gallons a day from water buffaloes they fill offsite.

“We don’t even have a water tap here yet,” Nick laughed.

And when the weather turns truly frigid, say 10 degrees from Thursday’s overnight snow, a conscientious farmer can check on the baby bibb while sitting at home in bed with a laptop. 

“If anything isn’t running optimally, the farm will literally send me a text message,” Nick said, waving his iPhone over the transplanting tables. Sensors throughout the trailer are connected to wi-fi. 

Independent experts on vertical, hydroponic farming say they can’t predict the success of Ullr’s business model, but agree the revolution in well-designed shipping containers could indeed preserve the environment and extend better nutrition to remote consumers. 

Rising world population, scarce water amid climate change and urban neighborhoods neglected by fresh food stores, “these are the multifaceted reasons why we’re seeing this surge in interest,” said Josh Craver, an assistant professor in controlled environment horticulture at Colorado State University. 

“It’s not hard to see pretty quickly that you can produce, per square foot, way more food in these containers than you can in the field,” Craver said. 

— Nick Millisor, one of the brothers behind Ullr’s Garden

The Ullr’s Garden name for their parking lot container farm honors the brothers’ time growing up skiing in Breckenridge, home to the Ullr Fest winter sports party. Nick Millisor comes at farming with all the technical skills of a self-described liberal arts eclectic and sci-fi nerd. He’d been toiling in real estate when the strange winds of COVID and climate change turned his 2021 upside down and he went in search of a meaningful project to better the world. 

There was a week where Germany flooded and the West was burning and a Canadian heat wave was cooking shellfish alive in the ocean. 

“I didn’t want to deal with super-rich people’s problems with real estate anymore,” Nick Millisor said. “And so I convinced my brother to join me, and then my cousin, and I was like, ‘You just want to do something crazy and start growing food in a container?’ And they said yes.” 

Luke Millisor supplied the actual technical knowledge, from his experience managing a neuroscience lab at University of Colorado. Colorado’s increasing water challenges led them toward water-stingy hydroponic farming and to the equipment catalogs of storage container outfitters. 

“We’re not the only ones doing this you know. I would love to say that we’re the pioneers behind this, but a lot of smarter people have basically led us to this point where this technology is almost automatic,” Nick Millisor said. “It’s so easy. I mean, I have zero experience farming, other than growing some stuff in my mom’s garden as a kid.” 

The container outfitters supplied a two-day boot camp on vertical farming.

The would-be farmers learned there’s almost zero water use in the latest designs, no contamination of runoff with excess fertilizer or pesticides, precise control of nutrients, efficient LED lighting powered by clean electricity. They have two electric vehicles to deliver produce within a 5-mile radius, boosting their effort to become carbon neutral with the overall operation. Leaving the root ball on a head of lettuce helps it last on the shelf for a couple of weeks and reduces food waste.

A fully outfitted container, with 24,000 individual LED pinpoint lights and temperature controlled at 68 to 70 degrees, costs about $170,000, Nick Millisor said. Ullr’s Garden can grow 500 varieties of produce to meet the whims of the market, and tweak the grow lights for goals as esoteric as the optimal color of a red lettuce leaf. 

Produce growing in a hydroponic farm in South Denver, compared with a view under thousands of red and blue LED lights. (Olivia Sun, The Colorado Sun via Report for America)

Accelerating efficiencies in lighting and heating have powered the surge in hydroponic container farms, said CSU’s Craver. Old grow lamps built up too much heat, while improved LEDs produce precise photons that the plant can employ for photosynthesis.

“So we really are sitting on the shoulders of giants on this one,” Nick Millisor said. 

As the water drips down the wall channels and then recirculates, sensors constantly check pH and mineral levels, among other growth factors. Reserve tanks dribble in supplement adjustments to the mix at the touch of the iPad. Key in siting the containers is pouring concrete footings at a 2% tilt to guarantee the water flow. 

Most varieties started from seeds are ready in six to seven weeks. Harvesting means clean scissors trimming the walls, or pulling whole heads with root balls. 

Now, about that business model. Negotiating with individual restaurants may not be the full answer, though Ullr’s Garden is in talks with a few looking for local supply and input into the varieties. The next challenge for the Millisors, joined by cousin and chief financial officer Ian Randall, is to launch a farm share program.

Varieties of lettuce seeds at Ullr’s Garden are inserted into biodegradable foam and watered twice a day with phosphates, nitrates, and other powdered nutrients mixed with water. (Olivia Sun, The Colorado Sun via Report for America)

Other farm share subscriptions are popular in summer and fall, with buyers picking up or getting delivered a box of outdoors-grown seasonal items ranging from lettuce to tomatoes to squash. But the outdoor shares run out by late fall, where Ullr’s Garden can deliver lettuce, herbs and other greens year-round. The company has 150 shares on sale now, to be delivered within the 5-mile radius. 

A prime calculation in close-quarters farming, Craver said, is which plants draw top dollar for the space they take up. Corn is all fibrous scaffolding, producing a handful of kernels that sell for 25 cents an ear. Root ball lettuce is nearly 100% edible, and can retail for $5 or $6 a head. 

There are large hydroponic operations in metro Denver that appear to be thriving, Craver said, and smaller operations like Ullr’s Garden are busy figuring out their costs and a workable scale. 

“When you look at the business model, it definitely does work,” Craver said. 

— Nick Millisor, one of the brothers behind Ullr’s Garden

Of course, there’s a lucrative container model selling billions of dollars of product a year in Colorado — marijuana. The Millisors, though, are adamant they want to feed the world, not medicate it. 

Denver’s zoning office is well organized to approve urban farming, Nick Millisor said, but they did have to address the elephant in the container. 

“I was like, ‘I’m doing a hydroponic garden,’ and you could just see it in their eyes, oh no, there’s another one, and I was like, ‘Not marijuana! Not marijuana!’ And she’s like, okay, STAMP, get out of here.’ ” 

The Ullr’s Garden trio plots their next move from underneath the modest shed looking out on the lot. If marketing picks up and the consumer-direct shares work out, there’s room for expansion with ground space for two or three more containers. 

Plus, as anyone who’s seen a modern port city can tell you, they’re stackable. Ullr’s Garden anticipates going at least a second story of vertical, and perhaps more if the zoning folks are feeling frisky. 

They’re considering transforming the shed into an events and education space, knowing that schoolchildren would thrive on a cool hydroponics and LED lesson. As for the produce, they’re still considering winter decorative flowers, edible flowers that could draw top dollar, and radishes. One grower figured out how to do hops indoors, another grew berries, though that may not scale up to be useful. 

One constant, besides the 68 degrees inside the trailers, is how welcoming and helpful everyone in vertical farming has been in sharing tips with Ullr’s Garden, Nick Millisor said. 

“Everyone has the tool. Now everyone’s kind of figuring out how best to use it,” he said. “And that’s what I think is most exciting for me.”

Michael Booth is a Colorado Sun reporter covering health, health policy and the environment. Email: Twitter: More by Michael Booth

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Vertical farming in Denver: Ullr's Garden is trying to save the world

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