Joshua Hargrove had sworn off leafy greens, berries and just about anything else that grew in the ground.
The 24-year-old Howard University law student has spent weeks steering clear of produce, unnerved by cyclospora outbreaks that have made thousands of people sick this summer.
Then, on his way home from a run, he stumbled on a loophole: a neighborhood farmers market.
“It was perfect,” he said, and loaded up on blackberries he no longer trusted to buy at the supermarket. “These are probably safer than if I were to get them at the store.”
The surge in foodborne illnesses has sent parasite-wary consumers flocking to farmers markets across the country. FreshFarm—operator of the market Hargrove visited and 24 others in the Washington, D.C., area—has had a 30% increase in average foot traffic since early July, said Cat Oakar, the group’s executive director.
“Farmers markets offer something that’s really valuable right now, and that’s transparency,” Oakar said. “You’re able to know exactly how it was grown, how it was packaged, what hands were touching it, what machinery was touching it, and how it got to the market.”
Eli Cook, a 47-year-old farmer who runs Spring Valley Farm & Orchard in West Virginia, has been selling fresh produce at markets since he was 12. He expected a typical midsummer slump in his D.C. farmers market sales this year, as shoppers are lured away by vacations and back-to-school shopping.
Instead, he has broken his sales record.
“Demand for lettuce is like nothing I’ve ever seen,” Cook said. On the mid-July day when he began making social-media posts contrasting the risks of his vegetables to store-bought produce, he sold roughly $7,000 of lettuce—triple his normal sales. To keep up with demand, he has started planting 3 acres of fresh lettuce every other week, rather than his typical 1 acre.
Meanwhile, in U.S. supermarkets, fresh-lettuce sales are sliding, and California farmers are plowing their crops back into the ground as demand slumps. Americans bought around 7.6 million less pounds of lettuce in the four weeks ended July 18 compared with the same period a year earlier, according to data from NielsenIQ.
“The scares are not good for everybody else, but sometimes they can really drive business for us,” Cook said. Early in the Covid-19 pandemic, he said, farmers markets saw a similar boom at the expense of traditional grocers, as shoppers were drawn by the opportunity to shop in the open air.
At the D.C. farmers market, produce prices are many times higher than what supermarkets charge a few blocks away. Some stands sold small cartons of cherry tomatoes for $7, bunches of kale for $4 and a mixed-salad bag for $5. Others displayed muffins for $10.50 and breakfast biscuits for $12.
Antoine Summers, a 56-year-old chef who comes to the farmers market every weekend with his daughter and dog, noted that one bag of spinach was $5. “If you go up to the Safeway now, it’s two for five,” he said. Still, he said, steeper prices are worth it for the peace of mind he feels knowing the food was sourced locally.
Letisha Steele is the chief executive of Green City Market, which operates two farmers markets in Chicago. In the past few weeks, she said, the markets have been buzzing with discussions of cyclospora.
“We hear it from staff, from shoppers, from farmers,” said Steele, who has been fielding more questions about how the food supply chain operates in the wake of the outbreaks. “Everyone is talking about it.”
In Michigan, the hardest-hit state in terms of number of cyclospora cases, farmers markets are going gangbusters because of the outbreaks, said Amanda Shreve, who runs the state’s farmers market association. So much so that farmers don’t always have the supplies to keep up with the flood of shoppers.
Many crops require weeks or months of preparation to grow and harvest, Shreve said, so boosting production is easier said than done. At a recent market on the lawn of the Michigan State Capitol building, several vendors sold out of fresh produce before closing time, she said.
At Golden Earthworm Organic Farm in Vermont, Maggie Wood said she received hundreds of requests to join her produce-distribution service in the weeks since cyclospora began making headlines.
“When everything’s great, nobody really thinks about where their food comes from,” she said. “Then when there’s a problem, they realize they’d rather buy their food from a farmer they know and trust.”
Leah Block, a 22-year-old freelance marketer based in San Diego, has long been wary of store-bought produce. But it was this summer’s cyclospora outbreak that pushed her to begin shopping at her local farm stand.
“It’s just been cool to connect with local farmers who are actually growing their produce,” said Block. “I feel like that’s so much more rewarding than just walking into a Trader Joe’s or Whole Foods.”
Hargrove said his father, a Marine Corps veteran, switched his diet after the outbreaks and has become increasingly distrustful of Food and Drug Administration food-safety guidelines.
“Right now I think in the media, there’s probably just sensationalism. It probably isn’t as bad as it seems right now,” Hargrove said. “But just to be on the safer side, it’s like, stick to alternatives.”
Write to Amira McKee at amira.mckee@wsj.com and Maya Davis at maya.davis@wsj.com