413: Hop Scientists Megan Twomey and Ryan Christian Share the Latest on Virus-Free Hops

At the turn of the 21st century, it wasn’t uncommon for a hop grower focusing on alpha varieties to replant a field every 25 to 50 years. While the plants in the field inevitably contracted viruses, the impact of those viruses on alpha-acid development and overall yield was manageable. In today’s environment, however—with new varieties bred to be high-performance, high-aroma, well-oiled machines—the same viruses have an outsized effect, and a field’s lifespan may be just a quarter of what it used to be. Yet many growers have been extending the productive lives of those fields by planting virus-free rhizomes and plugs—plants grown from cuttings taken from portions of other hops plants where viruses can’t travel. In this episode, we talk with scientists and hop breeders Megan Twomey of Latitude 46 and Ryan Christian of Yakima Chief Ranches for perspective on how viruses affect hops, how virus-free plants are produced, how long plants can remain virus-free, and more—and how all of that ultimately affects what’s available to brewers. Through the conversation, they touch on: different viruses that affect hops how viruses affect lupulin production in modern hop varieties viral impact in producing genetically true-to-type but phenotypically out-of-spec hops “cleaning up” hops to create virus-free plants how and now not to monitor fields for viruses field dynamics from new plantings over the first few years how viral stress impacts plants and their flavor and aroma expression yield benefits from virus-free plantings And more. This episode is brought to you by: G&D Chillers ( https://gdchillers.com ) : For years G&D Chillers has chilled the beers you love, partnering with 3,000+ breweries across North America and beyond. With our 24/7 service and support, your brewery will never stop. Remote monitor your chiller for simple and fast access to all the information you need, and gain peace of mind your operation is running smoothly. Berkeley Yeast ( https://berkeleyyeast.com ) . Berkeley Yeast bioengineers ordinary strains and make them extraordinary—enhancing the flavors you want and eliminating the ones you don’t. Visit berkeleyyeast.com to learn more and start brewing with science on your side. Old Orchard ( https://www.oldorchard.com/brewer ) : As breweries expand beyond beer into other segments like mocktails and CBD beverages, Old Orchard is here to help. We can formulate custom blends featuring specialty ingredients. More information and free samples are waiting at oldorchard.com/brewer. Indie Hops ( https://indiehops.com ) Lórien seamlessly combines traditional elements of European noble hops with an elegant twang of American modernity. Learn more about Lórien and the rest of Indie’s varieties at www.indiehops.com . Indie Hops — Life is short. Let’s make it flavorful. Steel Chill Cups ( https://SteelChillCups.com ) Steel Chill-Cups are the perfect promotional tool! Crafted from 100% recyclable steel and proudly made in the USA. Discover how Steel Chill-Cups can “Put your brand on every pour”—visit SteelChillCups.com today! Arryved ( https://www.arryved.com ) Not only does Arryved offer a world-class POS built specifically for breweries, but they also provide Arryved Brewery Management, e-commerce, and more to help breweries scale and thrive. Visit arryved.com to learn more. Probrew ( https://www.probrew.com ) Missed the ProBrew booth and their incredible product animations at CBC 2025? You can now experience them all right now at ProBrew.com! See how our advanced solutions can take your brewery to the next level! ProBrew, Brew YOUR Beer! Brewery Workshop ( https://breweryworkshop.com ) If you’re launching a brewery or acquiring an existing one, consider our brewery workshop and new brewery accelerator, September 14 through 17th in Fort Collins, Colorado. Over four days, we engage in panel discussions, technical brewery tours, networking, and small working group sessions that help you better understand and prepare for the challenges of brewery operation. Tickets are on sale now. Support Craft Beer & Brewing Magazine Podcast