SABIN, Minn. — The Sherwood Peterson farmstead looks like any farm you’ll find in the area with its tidy white buildings and freshly mown grass.

But tucked among the big, white Quonset, another out building and the windbreak of elm trees is what looks more like an “American Ninja Warrior" training course.

Recycled power poles border a rectangle of land. Black cargo netting hangs like Roman shades between the poles. And equally spaced ropes are suspended from cables strung across the plot.

The ropes aren’t there to train aspiring ninja warriors to climb. Instead, they’re there to train viney hop plants to climb, grow and mature.

Sherwood’s son, John D. Peterson, has cultivated this patch of hops for the last seven years and dubbed it the Mainline Hops Farm, named after the Mainline Potato Co., which his dad owned before retiring. John’s “farm” is just an 80- by 50-foot plot, but with this vertical, labor-intensive crop, that’s plenty.

Here, he grows two varieties of hops, the plant whose cones contain a sticky yellow resin called lupulin, which contributes bitterness to the beer, helps balance the sweetness of the malt and contains essential oils responsible for aroma and flavor.

One variety, Cascade — a flavor-adding hops known for its grapefruity zing — was recently harvested. The other, Nuggets, is a bittering hop, and could be ready for harvest any day now.

John and his business partner, Art Weidner, have sold their hops to local breweries, which traditionally have depended on the dried hops shipped from large producers in the top three hops-producing states, Washington, Oregon and Idaho.

This year’s harvest goes to Swing Barrel Brewing Co. , in Moorhead. “Nick, he’s the brewer and he was ecstatic they are getting this amount of wet (fresh) hops locally,” John says. “I mean, we do basically almost everything that they do out west. But you don't have taxes because we can sell directly to the brewer in Minnesota without paying taxes or sales tax as a farmer. And there's no delivery charge. It's just straight-up one price.”

Peterson believes marketing local hops would be easy. He points out that when local brewers have used locally grown hops, they’ve typically sold out quickly.

There’s no doubt that John loves talking hops. He can tell you about the most arcane details of the plant, which has been used as an essential ingredient in beer-making for well over 1,200 years.

A farm kid who grew up to be a research pharmacist, he keeps meticulous records of every significant date, weather event, pest-control measure and soil amendment related to the crop.

Weidner, on the other hand, can tell you about the solar-powered irrigation system he rigged up to give each of these thirsty plants the 3 to 6 gallons of water per day that they require. The water is collected from runoff from the Quonset and stored in a 3,000 gallon tank.

“I’m more the farmer,” John says. “He’s more the ‘I can build that’ guy.”

The two met while at North Dakota State University, where John was studying pharmacy and Weidner was studying mechanical engineering in the ‘90s. They bonded while cheering on Bison sports teams as the well-known “Hawaiian Shirt Guys” during the football team’s old Dakota Field days.

The idea for the project started in 2013 after PRACs Industries closed its doors and John lost his clinical research position there.

He decided to take a year off, during which he attended a hops-growing seminar hosted by the Minnesota Growers Association.

Then he started working on his dad to free up the grassy patch by the quonset for a hops plot. He figured the buildings and trees would provide shelter for the plants, which can start to lose hops in high winds.

“It took me about a year to negotiate with my dad on this little piece of property,” he says. “Eventually, I just said, ‘You know what? It’s going to be a big garden.’ And then it was OK.”

Sherwood Peterson was accustomed to more traditional crops with proven returns, like wheat, soybeans and barley.

But hops did grow on one branch of John’s family tree. His great-great uncle, John Erickson, was one of the pioneers and early mayors of Moorhead.

In the latter 1800s, Erickson owned a brewing company and had grown disgusted with the high price of importing hops. He decided to plant his own two acres along the Red River in Moorhead.

“So basically, I’m a fourth-generation hopper, twice removed,” John says.

Weidner shares an interest in raising hops plus has experience in marketing alcohol. He founded and owns North Dakota Sweet Crude, a craft liqueur company, based on a family recipe his ancestors started making on the family farm near Zap 100 years ago.

By 2014, John had broken ground and by 2015 they’d planted their first crop of rhizomes for the perennials, which can produce hops for up to 15 years.

Ropes, made of rough, fibrous coir, were suspended from a network of cables strung 18 feet above the ground. The rope provides the ideal “grabbing” surface for the first curling tendrils of the hops plant.

As the summer days lengthen and the plant gets more sun, it will continue to climb at a prodigious rate of a foot a day.

Three hops vines (technically called bines) are trained to climb the rope at a time, so that they coil around each other and form a thick column of grapevine-like leaves. Once the plant reaches the cable and the hop cones develop, a single bine can get as heavy as 20 pounds and produce well over one or two years pounds of cones.

The partners continually added improvements to help the hops thrive. John discovered the soil in that area was high in pH for the hops, which prefer levels below 7 or 6. He now adds sulfur amendments to the soil.

He also adds fish emulsion, guano and bison fertilizer to boost nitrogen levels and other nutrients.

Hops can be bitter, which means many animals will leave them alone. But bugs like grasshoppers will eat them. In order to get rid of the wrong kind of hops, John applies safe pesticides like neem oil to plants.

In efforts to cut down wind, they installed the Roman shades, which are made of mosquito netting and cargo netting, held in place by a support skeleton of aluminum cattle gates.

The shades “really cut down the brunt of the wind, especially the south side (of the plot) in summer,” John says.

The bines are ready to harvest when the cones are 80% water, John says. They then cut down each section of cone-laden bines.

In the past, they had to pick the hundreds of cones off each bine manually, which can take hours.

Their newest investment, the HopHarvester, saves considerable time, processing two to three bines per minute.

Once picked, the cones are poured into a large, rectangular, wooden box called an oast, which uses a furnace fan and then a dehumidifier to dry the cones to just 8% moisture. They're then vacuum-sealed in bags and frozen.

John takes these bags to Ostlie’s Sunnyside Acres near Carrington, North Dakota, where they are pelletized, packed into bags and flushed with nitrogen to flush out the oxygen that degrades the hops’ oils and beneficial properties. The hops then should last two years.

It’s a laborious process and, so far, not particularly profitable. They sell the hops for $10 pound, but it can be hard to find local breweries who can use the hops they produce from an operation that isn’t backyard-sized but isn't 20 acres either.

One year, Junkyard Brewing bought their hops and the beer made from them sold very well, John says. But then the brewer who was interested in their crop left.

In other years, they’ve sold to small brewers like Revelation Ale Work s in Hallock, Minn., which collaborated with Drastic Measures in Wadena.

From purely a money-making perspective, “if I could grow sugar beets, I would grow sugar beets,” John says.

But hops are more interesting. John would love to expand and grow two-row barley on the farm, which could then be malted and marketed, alongside the hops, as the local ingredients for a truly western Minnesota ale.

He also would like people to come out to the farm — from home brewers to brewery employees — to see first-hand how hops are grown. He's even invited people to pick some hops to bring home. “It’s just the education outreach I’ve always wanted to do,” he says.

But even if hop-farming hasn’t made the two friends rich overnight, they still enjoy it.

“It’s nice to come out here and work,” Weidner says. “And it’s just peaceful right by the trees.”

“This was just more of a therapeutic thing and I thought, you know, maybe I could make some money," John says. "And I think if we ever got to 5 acres, there would be money in it. But I'm not going to quit my day job. And doing it at this scale, I know exactly the things not to do.”

Learn about Mainline Hops on Facebook at @Mainlinehopsfarm