Published On: 12.31.23 | 

By: Rachel Damiani

Auburn University scientist leads research to help hops grow better in Alabama

Auburn University Assistant Professor Andre da Silva is paving the way in hops research and collaborating with the school's Brewing Science & Operations Program. (contributed)

Auburn University Assistant Professor Andre da Silva is conducting cutting-edge research on ways to grow hops in Alabama.

Da Silva’s work, within the Department of Horticulture, is in collaboration with faculty, industry leaders and students. And, as an Alabama Extension vegetable specialist, da Silva shares his findings with growers and brewers.

“Our goal is to provide information from the bine (the long flexible stem of climbing plants) to the tap, reaching hop producers, brewers and consumers,” da Silva said.

Da Silva, a recent recipient of the Professional Early Career Award from the American Society for Horticultural Science, has received multiple grants from both Auburn and the U.S. Department of Agriculture (USDA) totaling approximately $200,000. The aim of his research is to uncover how to grow hops in Alabama by identifying suitable varieties, or cultivars, and providing recommended crop management practices.

Hops — the flower, or cone portion, of the perennial Humulus Lupulus plant — is a key ingredient in beer for its preservative properties, flavor and smell.

“The beer industry has steadily increased in the last two decades, but they rely on hops being imported. So, if we have our own hops with high quality, that would be ideal for the local brewery industry,” da Silva said.

About 98% of U.S. hops are grown in the Pacific Northwest. Hops plants are finicky, da Silva said. They require about 16 hours of sunlight and moderate temperatures. If the conditions deviate from the desired range — such as in the Southeast, which has shorter days and higher temperatures — they won’t grow well.

But if the hops plants get what they need, their growth is astonishing. Hops plants can grow up to 10 inches a day and reach a maximum height of 12 to 18 feet, requiring even the tallest scientists to use a ladder when harvesting hops.

Da Silva, who has published more than 90 peer-reviewed research and extension papers and amassed more than $2 million in funding, is working to overcome the challenging climate conditions in Alabama by conducting research at Auburn’s campus greenhouse and in the “hop yard” in the E.V. Smith Research Center and in the Ornamental Horticulture Research Center.

Michael Phillips, a former Auburn undergraduate research assistant, tends to hop plants, which can grow 12-18 feet tall. (contributed)

He has tested two different mulching systems by covering plants in the hop yard with pine bark or black fabric and comparing their growth and soil moisture to un-mulched plants. The results show hop growth and soil moisture were highest for the mulched or covered plants.

“When we start to use those fabrics, we warm the soil and induce water intake and plants will grow faster,” he said.

Da Silva also has investigated which cultivars of hops plants are best suited for Auburn’s dry, hot conditions. He planted 16 different cultivars side by side in the greenhouse and then subjected them to water stress. The results indicate that Cascade and Chinook may be well suited for Alabama. Simultaneously, he surveyed brewers about preferred cultivars.

Da Silva is also collaborating with Alex Harkess, an adjunct faculty member in the College of Agriculture and a faculty investigator at HudsonAlpha Institute for Biotechnology, to promote efficiency related to harvesting hops.

“The plant can be either male or female, but only the females make those big, beautiful hop cones that are useful for beer productions,” Harkess said. “So, in a species that is 50-50 male and female, only half your crop that you plant from seed or cuttings will end up being useful.”

Ideally, growers would be able to plant only the profitable female plants. The problem: male and female seeds look identical.

That’s where genetics come in. The scientists have worked together to better understand “what makes a male a male and a female a female” at the genetic level by leveraging genome sequencing approaches, Harkess said.

Their initial findings served as important preliminary data for a USDA National Institute of Food and Agriculture fellowship obtained by Sarah Carey, a postdoctoral associate at HudsonAlpha who is mentored by Harkess. Among her goals: focusing on identifying genes that determine sex on the hops plant and creating a reference genome for multiple hop plant varieties.

“Auburn, being the land-grant institute in the state, has some of the best expertise in the Southeast for growing diverse crops in diverse places,” Harkess said. “And what HudsonAlpha has expertise in is doing large-scale genome sequencing and plant genotyping, so those two really go hand in hand together.”

Hops are the flower, or cone portion, of the perennial Humulus Lupulus plant. (contributed)

Sharing science with growers, and hops with brewers

Da Silva’s work doesn’t stop with the scientific results; he actively works to translate his findings for growers. He meets with them regularly to share information about best practices.

The connection between growers and brewers is being piloted on campus as part of the FoodU initiative, a collaboration between the College of Agriculture and Auburn’s Brewing Science and Operations program within the College of Human Sciences, said Desmond Layne, head of the Department of Horticulture.

“We are proud of our FoodU campus initiative and our ever-increasing number of talented partners,” Layne said. “FoodU links the growing of specialty crops with the utilization of those crops for food in campus dining and the culinary sciences program and also for aesthetic and future value-added purposes.”

As part of FoodU, da Silva began working closely with Clark Danderson, an assistant professor and director of the Brewing Science and Operations program, to see whether hops grown in Alabama could help create high-quality beer.

Auburn University Assistant Professor Andre da Silva. (contributed)

The team expanded when Layne introduced da Silva to Drew Kostic, head brewer and general manager at New Realm Brewing.

Their goal: bring da Silva’s hops to create an Auburn beer by the fall 2024 football season.

“The excitement was palpable on both sides,” said Kostic, a graduate of Auburn’s Brewing Science and Operations Program. “This type of collaboration is what I’m here to do — work with the state and the community to make the best possible beer we can and help put Alabama beer on the map further.”

They may even get festive with their offerings, using pumpkins grown from da Silva’s research to make a fall-themed beer.

The collaboration taps into the locally sourced food movement and has caught the interest of others looking to replicate their partnership across the country, Kostic said.

Another benefit: students, including future leaders in the hospitality management industry within the Horst Schulze School of Hospitality Management, will have a hands-on educational experience through their involvement with New Realm Brewing within the Tony & Libba Rane Culinary Science Center.

Danderson said he plans to share insights about local hops and da Silva’s research with his brewing science students.

“What we’re here to do is really make Alabama beer and beer across the United States better by working together, partnering with each other and sharing this knowledge with our students,” Kostic said.

Da Silva said hops research and yield will be bolstered by Auburn’s new hop yard in Mobile that can accommodate 300 plants. “We’re going to be able to provide hops in larger scales so that we can provide bigger batches to the Auburn brewery,” da Silva said.

This story originally appeared on Auburn University’s website.