Children's National Medical Center is one of 10 weekly stops for the Arcadia Mobile Market, which serves neighborhoods where fresh produce is hard to come by. (Mary F. Calvert/For The Washington Post)

At about 1 p.m. on a recent Wednesday, the Arcadia Mobile Market team is almost done setting up its roving farmers market stand at Children’s National Medical Center.

LaToya Johnson is ready to shop. And has been since 9:45 a.m.

Johnson, pregnant with her fifth child and with her 1-year-old son in tow, had been visiting the hospital’s Women, Infants and Children (WIC) clinic, where she learned about the market that trundles around Washington in a converted bright green school bus and makes a weekly stop on a patch of grass steps from the building’s entrance.

The closest grocery store to Johnson’s home off Rhode Island Avenue is a Giant, where Johnson says her money doesn’t go that far. At the Arcadia stand, Johnson can use vouchers she receives through WIC’s supplemental nutrition program, with Arcadia matching those funds. That’s not to mention the city’s new Produce Plus Program, which provides an additional $10 per week per distribution site for qualifying families.

“Coming here, I’m saving myself $40, really,” she says.

Perhaps even more than the money, though, Johnson is swayed by the quality of farmers market produce, which she has become adept at sneaking into her children’s meals.

“It’s fresh,” she says. “You can touch it. You can feel it.” And, she adds, “you know you’re helping the community” by buying local.

Those kinds of proclamations are music to the ears of Benjamin Bartley, food access director for the Arcadia Center for Sustainable Food and Agriculture. Arcadia, a nonprofit organization founded by Neighborhood Restaurant Group owner Michael Babin and based at Woodlawn Estate, in the Alexandria area of Fairfax County, is in its third mobile market season. Bartley, 28, has been at the helm of the initiative since the beginning.

The mobile market makes 10 stops each week, nine in Washington and one in Alexandria. Thanks to a partnership with Martha’s Table, a second vehicle will visit an additional eight sites starting next month, with one stop in Maryland and the rest in the District.

Arcadia will sell to anybody, but its primary objective is to reach out to residents most in need of reasonably priced produce. Those populations include people receiving nutritional assistance from WIC, as well as SNAP (Supplemental Nutrition Assistance Program, or food stamps), the Seniors Farmers’ Market Nutrition program and Fruit and Vegetable Prescription, a collaborative program launched by DC Greens, Unity Health Care and Wholesome Wave that allows doctors to write “prescriptions” for free farmers market produce.

Bartley acknowledges that the patchwork of vouchers and matching funds, plus cash and debit or credit cards, can make ringing up customers a challenge. “We accept many forms of payment and are definitely better off for it,” he says.

Bartley targets neighborhoods where fresh produce is hard to come by. So in the off-season, when he’s no longer working 12-hour-plus days, bouncing between market stops, the group’s commissary and Arcadia’s Alexandria and Middleburg farms, he crunches numbers to choose where the mobile market will go. He looks at where stores and other farmers markets operate, the density of homes enrolled in SNAP, median income and anchor sites that might be willing to host the market and assist with outreach.

Part of the goal is to demonstrate to stores and other markets that these locations are worthy of a permanent operation. “We want to work ourselves out of a job,” Bartley says. “We are a bridge. This is not a permanent solution.”

Until that solution arrives, whatever it might be, Bartley and his colleagues will have plenty to do.

Wednesday is the busiest day for the mobile market. From 9 to 11 a.m., it visits the Congress Heights Senior Wellness Center in Southeast. Children’s National occupies the 1-to-3-p.m. window. The final stop of the day is LeDroit Park, from 5 to 7 p.m.

Bartley has started his day around 7 a.m., picking up excess bread from Lyon Bakery in Union Market, where he parks his bus and can plug in the two refrigerators and one freezer onboard the bus overnight.

Several people are needed to run the market, and today Bartley’s colleagues include JuJu Harris, Arcadia’s culinary educator and SNAP outreach coordinator; and summer fellow Anna Hymanson, a rising junior at Tufts University’s Jonathan M. Tisch College of Citizenship and Public Service.

The group efficiently sets up shop at the wellness center. Tents and an awning come out to keep people and products cool. Crates holding bundles of greens, boxes of strawberries and glass jars filled with herbs are placed on the side of the bus on removable metal shelves. The market also sells local meat, eggs, dairy and honey, which, like the produce, is a mix of items from Arcadia and other local farms.

Not long after the market opens, regular customer Mayada Mannan walks away with several bags of food, saying she appreciates the pesticide-free items she can’t buy elsewhere in the area.

A few other customers and curious onlookers stop by. “The morning stops are a little slow,” Bartley explains. “The first month is slow, too.”

Harris spends some of the time prepping ingredients for what she calls her “kale salad show,” a demo of her popular garlicky kale salad she’ll do at the next stop. Harris recently published “The Arcadia Mobile Market Seasonal Cookbook,” which sells for $20 at the market but is free for customers receiving nutrition assistance.

When it’s time to move on, Hymanson sets the timer, as the group is informally competitive about how quickly they can break everything down. A lot of precise stacking is required, using one of what Harris affectionately calls Bartley’s “Ben-ventions,” a series of wooden frames that prevents things from sliding around.

At Children’s National, a decent crowd of WIC patients and hospital employees streams through. Many appreciatively toss back plastic-cup “shots” of Harris’s salad.

The final stop, in LeDroit Park, is Bartley’s favorite. It’s lively and diverse, with customers including seniors, millennials in workout gear and children angling for samples.

LeDroit Park Civic Association President Golda Philip joins Bartley’s team and other volunteers to help distribute the while-supplies-last Produce Plus checks. To avoid conflict of interest, Bartley, as a vendor, can’t distribute the checks, which is why he is working with other groups and sites to reach eligible customers.

Edna Bryant, a LeDroit resident everyone calls “Grandma,” is one of them. For her, the market is a lifeline. “I can come over and shop and not spend any money,” she says.

Halbert Copeland is another market fan who collects Produce Plus checks from Philip. He likes to get his produce from Arcadia, especially because grocery stores are farther away and neighborhood stores are more expensive.

Every week, the Arcadia team expects to see Copeland and other regulars they’ve built a rapport with. The mobile market runs only through October, though. Harris worries about them after that.

“At the end of the season,” she says, “it’s like, gosh, what are they going to eat now?”