Sky High Farming in the Mile High City

BY Amy Antonation


Sky High Farming in the Mile High City

Dek goes here…

Colorado’s growing season is notoriously short—at least when you’re growing outdoors and subject to the whims of vast temperature swings, cold nights, devastating hail, and, of course, persistent drought. Hydroponic farming, or farming done without soil, definitely isn’t new in the Mile High (or anywhere else in our state). But its association with weed is waning as more large-scale greens growers—we mean lettuce, y’all—are taking root. Kalera, a vertical-farm behemoth with operations in three countries plus three U.S. states, has taken root in Denver, with its first harvest scheduled for May 2.

The company’s press release makes big, bold claims: that its greens are 50 percent more nutritionally dense than traditionally grown organic greens; that its operations use just three to five percent of the water used in traditional farming; and that the resulting product will “address and solve the issue of food inequality.”

Hydroponic farm lit by purple LED lights with scientists wearing lab coats work on seedlings.
Kalera employs a variety of tech, including a seed breeding program. / Courtesy Kalera

Fancy Plants

Curtis McWilliams, Kalera’s interim CEO, points to a couple of reasons for the nutritional density of the product . The vast majority of greens available in the U.S. are grown and harvested in California and Arizona, and transportation to Colorado takes about a week (and sometimes more). That’s time the already harvested plant is dying. Nutrients are waning and leaves are wilting, leaving a less healthy, less appetizing bunch of lettuce. Also, McWilliams notes, those products are “grown in dirt. As a result, they’re subject to E. coli and other pathogens. They’re subject to a caustic wash.” By contrast, he says, Kalera greens are grown in a “clean room” without pesticides and don’t require washing to eliminate those chemicals or pathogens. And, he says, “When you buy that product coming from the Denver facility, it’s harvested one or two days before. It’s still a living product; it has the root ball still on.”

Sally Herbert, the co-founder and CEO of Altius Urban Farms, a Denver-based hydroponic farm located in the Five Points neighborhood, concurs with McWilliams’ assessment. While Altius doesn’t make nutritional claims about its product, she agrees, “This [effect the time from harvest to mouth has on nutritional value] is the benefit overall of having hyper-local produce. It’s true of carrots and lettuce and basil”—and any other vegetable you can consume.

The other reason behind Kalera’s nutritional claims? Seed breeding. Last year, Kalera acquired Vindara, a seed development company that selectively develops seeds that will yield certain characteristics. McWilliams emphasizes these seeds aren’t genetically modified organisms (GMOs). “People have been doing it for hundreds of years,” he explains. “It’s not GMOs; it’s kind of like you do with dogs to derive certain attributes. There’s a lot of trial and error. You have to try one [seed] and grow it for a period of time [to see the results.]” Seeds can be developed to have greater hardiness and pest resistance, or for improved flavor, texture, or color.

Because Kalera’s products are grown indoors, McWilliams says, the company can focus on plants that taste exceptional and grow quickly rather than plants that can weather tough field conditions. Currently, it is developing a variety of fast-growing romaine lettuce. “Right now it takes us about 45 days to get a full-sized head of romaine,” says McWilliams. “We think we’ll be able to do it in around 30 or 35 days. It’s the same size, with slightly better nutrient content.” 

Does Size Matter?

With an 87,000 square feet facility filled with platforms of greens stacked 11 shelves high, that kind of reduction in growing cycle squeezes another two harvests per year (of romaine, at least) into Kalera’s schedule. Overall, the facility will produce 11 million heads of lettuce per year, or about 2.4 million pounds of greens. Half of that goes into restaurants and other food-service settings, with the other half ending up in grocery stores. McWilliams touts the product as ideal for restaurants, in large part because it comes in so clean. It doesn’t need to be washed or picked through for excessively dirty or spoiled leaves, and businesses don’t have to worry about bacterial contamination like E. coli. Kalera greens will be available wholesale through US Foods and Sysco, and will be showing up in King Soopers stores starting mid-May. (See its website for a store locator.)

Kalera is running farms in Orlando, Florida; Atlanta, Georgia; and Houston, Texas, with five other U.S. farms (including Denver) in development. In addition, there are operations in Munich and Kuwait, with a Singapore location scheduled to open in the third quarter of 2022. No doubt, It’s a massive operation. But it’s not the first vertical farm in the Denver area. Altius is perhaps the most recognizable (and best-known to restaurant goers); its sole location perches atop high-end sushi spot Uchi. But Herbert is quick to point out that Lakewood’s Infinite Harvest farm was in the climate-controlled farming game long before Altius’ first harvest in 2018 (Infinite Harvest began operations in 2009).

Altius’ sunny greenhouse is less than 10 percent the size of Kalera’s indoor farm. Lettuce, arugula, basil, and more sprout from eight-foot-tall growing towers that give rise to the moniker “aeroponic.” While Herbert declines to share the exact amount her farm yields, she says staff harvests about an acre’s worth (roughly 43,500 square feet) of greens every month. The greenhouse design of glass walls and clear polycarbonate roof also allows her greens to flourish under Colorado’s vaunted 300 days of sunlight. (Altius supplements sunlight with LED lighting during the winter months.) “We’re tapped out at our current location,” Herbert admits. “It’s a very small farm. We can’t grow much more in there.” She’s considering expanding but isn’t in a rush, content to wait for the optimal opportunity.

When Gotham Greens came to town [in 2020] with 30,000 square feet of lettuce production, we didn’t feel them at all, and we won’t feel Kalera.

Sally Herbert, Altius Urban Farms

Workers at Altius harvest produce five days per week, and the farm does one better than Kalera; the product gets delivered to restaurant and retail customers the same day it’s picked. A few customers request early morning deliveries, in which case the crop is picked in the afternoon, immediately stashed in an industrial cooler, and delivered first thing the next morning. “We harvest and deliver five days a week. We deliver nothing after 24 hours [of harvest],” Herbert emphasizes.

Like Kalera, Altius’ customers are split fairly evenly between restaurants (45 percent) and grocery stories (50 percent), with the remainder being sold direct to consumers via year-round community supported agriculture shares. Herbert notes Altius sells every last leaf of its product, and there’s a waiting list for potential customers. “We have a really short supply chain, and we take pride in that,” she says, nothing that if the farm expands, it may become difficult to maintain same-day delivery.

Despite being the little guy production-wise, Herbert isn’t concerned about Kalera entering Denver’s market. “There’s room for all of us,” she says emphatically. “When Gotham Greens came to town [in 2020] with 30,000 square feet of lettuce production, we didn’t feel them at all, and we won’t feel Kalera. Plus, we are a Colorado company. It doesn’t make us better, but some customers will choose local.”

Close-up of bright green sprouts.
Seedlings: Life finds a way. / Courtesy Kalera

Saving the World With Lettuce

Kalera’s press release doesn’t mince words. “How will the new Denver farm impact the greater metropolitan area?” it asks. “Kalera’s farms address and solve the issue of food inequity.” That’s a big ol’ claim in a complicated world. Of it, McWilliams says, “We want to bring high-quality, nutrient dense leafy greens—which should be the basis of our diet—to every locale possible. You don’t have to be near California or Arizona to have this at a reasonable price. We have certain proprietary technology (and there’s a certain amount of tech that you can use off the shelf) to ensure…our price is relatively competitive.” He points out that the forthcoming Singapore location will be located “where farmland is at a premium and everything has to be imported.” Kalera’s greens, he says, are priced slightly higher than traditionally grown conventional (non-organic) produce, but at a “significant discount” to organic produce. He credits the operation’s tech for keeping the price so low, and affirms, “We do believe this is the wave of the future. We just want to be at the forefront of it.”

The cost of transporting a head of lettuce to the midwest costs as much as the lettuce itself.

Curtis McWilliams, Kalera

Herbert has a different perspective. “There’s this whole other side of responsible farming,” she attests. “You’re never going to grow wheat and soybeans in a greenhouse. We need to change that stuff alongside indoor farming. There’s no one solution.” As an example, she points out that rockwool, the growing medium many hydro- and aeroponic farms use to grow crops, is technically compostible, but “most people don’t do that. They trash it. It’s made from rock and it breaks down but it takes forever.” She mentions modern regenerative agriculture practices that use drones to comb fields and collect data such as humidity and dew points. That, she says, is an excellent marriage of tech with more traditional farming techniques.

There’s also the question of price and accessibility. Herbert acknowledges Altius grows a premium product—with a price tag to match. Consumers can find Altius’ greens in Marczyk Fine Foods, Leevers Locavore, Nooch Vegan Market (all in Denver), and Nude Foods Market (a Boulder grocery that eschews all single-use packaging). The only hesitation Herbert may feel about the likes of Gotham Greens and Kalera opening Denver operations is related to pricing, though even that’s a minor concern. “There’s price competition, right? They might be able to drive the price down, but I’m not worried about that…I don’t feel animosity to them at all . I welcome it, because the carbon footprint of trucking this stuff from California…we need to be done with that.” McWilliams concurs, noting it’s as damaging from an economic perspective as it is from an environmental one. “With gas prices rising,” he says, “the cost of transporting a head of lettuce to the midwest costs as much as the lettuce itself.”

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Amy Antonation

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