Rod Koda, a veteran strawberry farmer on California’s Pacific Coast, is seeing a dramatic increase in his organic harvest after applying steam to his fields before planting. The steam‑treated plots produced almost twice as many berries as nearby conventional plots, and they suffered far less damage from fusarium wilt, a common fungal disease.
Steam as a chemical‑free alternative
For decades, growers have relied on chemical fumigants to sterilize soil, but those chemicals pose health risks to farmworkers and nearby residents. Researchers at the University of California, Santa Cruz have been adapting steam technology—long used in greenhouses—to open fields. By injecting hot vapor into the soil, the process kills disease‑causing organisms and weeds without leaving toxic residues.
“It’s a very noticeable difference,” Koda said of his steam‑treated rows. The method not only improves yield but also aligns with the growing demand for truly organic produce.
Industry support and ongoing research
Rick Tomlinson, president of the California Strawberry Commission, noted that the research team has been refining the technology for more than a decade. “Fundamentally, there’s this disease in the soil, and if you don’t have some solution, you’re just rolling the dice and one of the years you’re going to end up bankrupt,” he warned, emphasizing the economic stakes for growers.
University researcher Jenny Broome explained that the steam kills the fungal spores and weeds that would otherwise devastate a crop. Four California growers participated in the pilot trials last fall, and all reported higher yields and healthier plants.
Potential beyond strawberries
Broome believes the technique could be applied to other high‑value crops such as lettuce and carrots, though cost remains a hurdle. Engineers are working to make the steam machines faster and more affordable, aiming to cover larger acreage in less time.
“We’re going back to the future, where we’re looking back at an older technology but we’re finding more ways to engineer it more efficiently,” Broome said.
Environmental and health implications
David Andrews, chief science officer for the Environmental Working Group, welcomed the shift away from traditional fumigants. He highlighted that farmworkers and their families have long been exposed to hazardous chemicals, and that steam offers a safer alternative.
“The economics are shifting,” Andrews added, noting that as consumer demand for chemical‑free produce rises, growers have a financial incentive to adopt cleaner methods.
Looking ahead
California produces nine out of ten U.S. strawberries on roughly 35,000 acres, making it a critical state for the nation’s berry supply. If steam treatment proves cost‑effective at scale, it could reshape organic farming practices across the state and set a model for other regions seeking to reduce chemical inputs while maintaining productivity.
Original reporting: KCCI Des Moines — read the source article.
