Minneapolis leaders have promoted the redevelopment of 48 acres along the Mississippi river­front as a one-of-a-kind opportunity to bring life to an abandoned industrial zone.

Deep within the tract, in the corner of a crumbling warehouse, something is already growing. Edible mushrooms.

Since 2015, Mississippi Mushrooms has cultivated several varieties in the middle of the former Upper Harbor Terminal, and the farm supplies restaurants, stores and retail shoppers with up to a half-ton of mushrooms each week. Now, the farm's future is at risk as the city plans to redevelop the entire site with green space, housing, retail, an amphitheater and other amenities. The project's concept plan called for demolishing the 110,000-square-foot warehouse to make room for a park and to build a new hub for "green businesses" farther down the lot.

Mississippi Mushrooms is the most prominent business on the site, the type of sustainable and entrepreneurial company the city is looking to attract once the redevelopment is complete. Yet its founder and president, Ian Silver-Ramp, fears his farm won't survive the transition.

"It's always this existential threat," Silver-Ramp, 32, said from inside the warehouse offices this month. "I'd much rather spend my time in figuring out how to grow mushrooms better, right? But we have to devote time to figuring out how to not get put out of business by this thing."

Silver-Ramp said he worried the farm wouldn't be allowed inside a brand-new commercial building, and that rent would surpass the $2,500 a month he pays the city for warehouse space.

The City Council directed the city to conduct a cost-benefit analysis of keeping or replacing the warehouse. That report could be presented during the next council update on the redevelopment in May.

City officials leading the project, unsure of what the analysis will recommend, say a new building would better serve incoming businesses.

"It may be better to build a building that fits the needs of the tenants of the hub rather than trying to retrofit a building that already has many limits and is several decades old," said Ann Calvert, the city's principal project coordinator.

To Silver-Ramp, who grew up on the North Side and attended Patrick Henry High School, there is no other space like the Upper Harbor Terminal for what he does.

"I could move out to the country, but if I wanted to do that I would've done it in the first place," he said. "Half of what it is is trying to bring agriculture and make it more accessible for people who live in an urban area."

Started out of a basement

Silver-Ramp, who now lives in south Minneapolis, fell in love with fungus while studying agriculture at the University of Minnesota.

"I'd wanted to do it for years," he said. "Even beyond mushrooms, fungus has this huge potential to do a bunch of interesting things."

He started growing mushrooms in his basement and selling them at the West Broadway Farmers Market. Later, he moved the business to Northeast, where he stayed for two years before discovering the Upper Harbor Terminal.

The warehouse had everything he needed: high ceilings, floor drains, electricity and room to grow. Trucks could come in to unload materials, and he was able to compost piles of wood chips outside.

The strong, musty smell of substrate, or "fungus food," emanates upon opening the door to the farm. A giant, smiling Humpty Dumpty sits on a shipping container looming over the entrance, and a psychedelic Grateful Dead banner hangs behind the counter.

Silver-Ramp and his small team now grow mushrooms year-round. Bags of substrate are sterilized and mixed with mushroom spawn before they're moved to shelves on the southern wall of the warehouse, where the fungus is incubated (Silver-Ramp calls it the "nonsexual stage of the fungus").

The bags are then moved inside one of the hand-built grow rooms, where the temperature and humidity are controlled with a smartphone app. It is here where clusters of oyster, poplar, shiitake and nameko mushrooms begin to grow.

The business has more than doubled in size since it moved back to the North Side, now occupying about 9 percent of the warehouse. He delivers to local restaurants (Young Joni, Bacio), breweries (Surly Brewing Co.) and grocery stores (the Seward and Wedge community co-ops), a benefit of being in a central location.

"If this [redevelopment] were not happening, I would still be dreaming about taking over the whole warehouse someday," he said.

Trying to fit in

The development team, led by United Properties, is still figuring out what the hub will look like and what types of businesses it will hold. The concept plan describes a mixed-use building that could include a greenhouse, a hydroponics farming area and an indoor market. The first floor would be owned by the community.

While Calvert believes Mississippi Mushrooms could be a good fit within the redevelopment, that may not be in the warehouse itself.

"It's a very big building," Calvert said of the warehouse. "It really limits how much room there is between the building and the riverfront for trails and that sort of thing."

Mississippi Mushrooms co-owner Jason Lund, a freelance graphic designer, is supportive of the redevelopment. He just wants the mushroom farm to be a part of it, too.

"It's definitely good to fix this area up. It's kind of become an industrial wasteland," he said, wearing a white coverall and a disposable facemask. "But it totally sucks if they're gonna tear down this building and we get displaced. That's the only bummer of it all."

Miguel Otárola • 612-673-4753