ST. PAUL, Oregon — The first hint of harvest time in one of the nation's major hop-growing regions is obvious: All along the backroads of Oregon's Willamette Valley are trucks overflowing with ropes of bouncy, freshly cut hops dropping their distinctive bright green cones on blacktop warmed by the early September sun.
Then there's the fragrance.
Fresh hops smell sweet like ripe berries, citrusy like an orange peel, and earthy like newly cut grass. It's a crisp, refreshing scent, but not yet boozy like beer. The aroma intensifies as the trucks approach the processing facilities. There, the resinous cones are stripped by machines from the bines they grew on all summer, dried in kilns and then shipped to breweries or brokers.
Multiple factors contribute to the unique flavor and aroma of hops grown in the Pacific Northwest. In Washington, which grows 73% of hops in America, it's the drier conditions of the Yakima Valley. In Oregon, it's the loamy river bottom soil, the temperate nights and the long summer days.
Such characteristics, known as terroir, have long been used in the wine industry to define how the soil, climate and environment of a region affect the taste of grapes.
Now, hop growers want to better understand and more clearly define the terroir of hops, the dominant flavoring agent in beer. Researchers at Oregon State University are trying to determine whether the same sort of hops grown in different parts of the Pacific Northwest might have different aromas and characteristics that bring distinctive tastes to beer. (Beer is made from water, grain, yeast and hops.)
The research could help growers define the terroir of the distinct hop-growing regions of Washington, Idaho and Oregon. It also might help farmers and researchers identify specific growing conditions — soil, water, temperature or other characteristics — they could replicate to offer more of the hop varieties most sought by brewers.
“There’s three different river bottoms we farm in, and all three are different,” said John Coleman, a sixth-generation Oregon hop farmer who, along with his wife, Liz Coleman, spurred the research into terroir. “We’re still trying to understand why they’re different, but it creates an opportunity for us to talk to the brewers who want to come out and see where their hops are coming from.”
Origins of Terroir
Liz and John Coleman became curious about hop terroir in 2017 after they visited a winery with some of their interns and learned about soil regionality. Intrigued by whether hops might also have a terroir, Liz Coleman reached out to Tom Shellhammer, an Oregon State professor who studies the chemistry of hops.
At the time, the multigenerational family farming enterprise, Coleman Agriculture, had four operating hop farms that were 40 miles apart from one another in some places. (The Colemans now operate a separate hop-growing venture, Westwood Farms.)
The first phase of the study looked at the differences in the Coleman hop farms, but in subsequent years expanded to other Oregon growers, and then to the potential of different terroirs in Washington, too.
"There are a lot of growers that are very excited about this idea of hops terroir, because it can help producers be empowered with the unique marketability of hops," said Maggie Elliot, the science and communications director for Hop Growers of America, based in Yakima, Washington.
The Yakima Valley is well known for its wines, but even with its history as the nation's largest hop-producing region, state tourism officials say beer hasn't historically drawn as many visitors. The exception is during the hop harvest, when brewers from around the world come to select fresh hops, said Jennifer Martinkus, the marketing manager for Yakima Valley Tourism.
Yet over the past four years, the number of people planning visits around craft beer has grown to nearly match, if not exceed, the region's wine tourism, she said. Many visitors arrive in fall, when fresh hop ales are on tap for a limited time, including at the Fresh Hop Ale Festival in early October. The tourism agency is studying visitor tracking data to better understand the impact of the craft beer industry on the regional economy.
"September and October are our busiest times for craft beer tourism," Martinkus said. "Given the steady growth of craft beer tourism, I certainly see it becoming an even more significant driver for visitor days here in the Yakima Valley."
For decades, hops mostly were a commodity crop purchased and blended by large brewers, including Anheuser-Busch, which once had contracts to buy Coleman Agriculture hops in Oregon. Brokers or suppliers would distribute the hops to buyers; growers had few direct relationships with individual brewers. But after the beverage giant InBev bought Anheuser-Busch, Coleman Agriculture's contract ended. The family business in 2010 dropped from 900 to 100 acres of cultivated hops, said John Coleman, who considered abandoning them entirely.
Then came the craft brewing revolution of the past decade, driven in part by the popularity of hoppy, India pale ale beers. Many Oregon hop growers began cultivating relationships with craft brewers. And, ultimately, they began considering terroir and how it might distinguish their hops as a regional crop. The Oregon legislature, too, has made significant investments in fermentation science research, in part to cultivate a skilled workforce to support the state's wine and beer industry.
Craft brewers will ask for hop varieties by name and state, said Michelle Palacios of the Oregon Hop Commission. Some even specify which field they prefer their hops to come from, demonstrating for many growers the importance of terroir. And some brewers can even identify specific varieties grown in specific places, based purely on their aroma.
"A brewer will often say 'I want Cascade,'" Palacios said. "And when they select the lot based on how they're going to use it, they may lean towards an Oregon Cascade. They may lean towards a Washington-grown Cascade. So, it has the basic aroma qualities, but those subtle differences are what make the final selection. Like, 'This is just slightly more floral. This is slightly more citrus, it's got more melon,' as an example. Those slight differences will help a brewer make the final decision."
Hops nationally are a $662 million crop, according to the U.S. Department of Agriculture's 2021 National Hop Report. Nearly all of the national supply is grown in Washington, Idaho and Oregon. Worldwide, American hops account for about 40% of the global supply, more than any other country, including Germany. Outside of Washington, about 16% of American hops grow in Idaho; Oregon accounts for about 11%. Both Michigan and New York also grow some hops.
A perennial crop that goes dormant in the winter, hops grow in fields known as hop yards, up 18-foot-high trellises strung with wires. The bines grow from the ground up ropes, in Oregon reaching the top wire on the trellis around the Fourth of July. That's 18 feet of growth in about three months, said David Henze, president of Coleman Agriculture. The cones begin to set about three or four weeks before they're harvested, Henze said. Most hops are harvested in late August or early September, a joyful and busy time with a storied history since 1867 in Oregon.
On a tour of the Coleman operation during the harvest, Henze demonstrated how brewers smell the cones that flavor their beer. He took some freshly dried hop cones from the kiln and broke them apart to reveal the resinous lupulin at their heart. "One of the things with terroir, is it will affect that oil," he said.
Shellhammer's most recent study of terroir analyzed two types of hops from the 2020 harvest: Cascade and Mosaic. The hops were grown at 39 separate locations in Washington's Yakima Valley and Oregon's Willamette Valley.
Researchers performed a chemical analysis of the acids in the hops. They also put together a trained sensory panel to assess the aroma of the hops.
The research showed differences in the same kinds of hops grown in the two states. Beers brewed with 14 of the hop samples “revealed similar regional-dependent results,” according to the study. Cascade hops grown in Oregon had what were described as a "strong citrus, floral, fruity, herbal and resinous aroma." The same variety grown in Washington was characterized by a "more tropical and sweaty aroma." There were similar differences in the Mosaic hops from region to region, according to the study.
"Hop growers have always known that there are differences where the hops are grown, but what this study did was actually quantify it and actually give us the data to be able to back up what our instinct tells us," Palacios said.
Future studies at Oregon State will look at the differences between other hop varieties grown in the Pacific Northwest, and how they might change from harvest to harvest. Researchers also will look at factors including soil characteristics, the microbiome, weather and climatic conditions and how irrigation and fertilization affect terroir. They'll also study how the date the hops are harvested affects the aroma and flavor. What they learn may help hop growers cultivate resiliency as the climate changes, Elliot said.
"Looking forward, this industry is being challenged by the effects of a changing climate," she said. "And so, we're going to be needing these varieties that are tolerant to drought, that are tolerant to heat, that perhaps don't require as many inputs, whether that be fertilizer or plant protection tools."
Terrior on Tap
Brewers appreciate the additional research into what makes certain hop varieties so distinctive, said Sam Richardson, the brewmaster and co-founder of New York's Other Half Brewing in Brooklyn. Richardson, who was raised in Oregon and trained in fermentation science at Oregon State University, said he sources hops from all over the world, including his home state.
Although the East Coast beer drinkers drawn to Other Half's hoppier beers may be familiar with regional differences in hops, Richardson said, they're most likely to be drawn to a specific type of hop they like, no matter where it's grown.
"Customers do recognize hop brand names, and people that drink a lot of really hoppy beer tend to know what those hops taste like in a beer," Richardson said. "So, they kind of know what they're getting into already and they may seek it out just because of the name. In general, people just want the hop brand names that they know and recognize and love, whether that's from Australia, the U.S. or Europe."
Down the road from Coleman Agriculture is Crosby Hop Farm, another legacy grower in Oregon. Hundreds of people often gather on sunny summer afternoons at TopWire Hop Project, a beer garden that opened in 2020 in the farm's hop fields. There, bartenders serve beer on tap made with hops grown on the farm by breweries around the country.
Each beer lists which type of hops were used. Bartenders use tongs to garnish each draft beer with a freshly plucked cone.
At TopWire on a sunny early September day, surrounded by ripe hops and the smell from the kilns, it's not difficult to image how the soil and even the marine breezes and the air temperature contribute to a sense of place evoked by terroir.
"Now more than ever, people are curious and want to know where their food is coming from," said Liz Coleman. "It's been motivating for the brewer and the supplier, and now the grower. It was a long way between the grower and the end consumer. And so now there's just this very beautiful connection all the way from farm to drink, that everyone is involved in."