NEW YORK — On the busy commercial strip along Knickerbocker Avenue in Brooklyn’s Bushwick neighborhood are all the shops one might expect to find in a poor area branded a “food desert”: two 99-cent stores, a check-cashing center and plenty of pizza and fried chicken joints. But thanks to Alfonso Victor and Elena Ferreira, there’s also an oasis of fresh fruits and vegetables. Just about every weekday for the past three years, even in the depths of winter, the couple has set up a produce cart here, piled high with pineapples, tangerines, lettuce, tomatoes and specialty items for the area’s Latino community, such as plantains, yucca, hot peppers and cilantro.

Victor, from Mexico, and Ferreira, from the Dominican Republic, are two of more than 500 vendors who participate in New York’s Green Cart program, which puts fruit and vegetable carts on the streets in low-income areas with high rates of obesity and diet-related diseases. Though green carts are only one of several city strategies designed to encourage consumption of more-healthful food, there is early evidence it is working: In New York’s high-poverty neighborhoods, the percentage of adults who said they ate no fruits or vegetables during the previous day is slowly dropping, from 19 percent in 2004 to 15 percent in 2010.

Alarming statistics — more than 70 million Americans are now considered obese — and first lady Michelle Obama’s “Let’s Move” campaign have focused national attention on efforts to make healthful food more accessible and affordable. New York’s Green Cart program is fast becoming a model for other American cities. Philadelphia launched its Healthy Carts program in 2011. Similar programs are being introduced in the District; Chicago; Los Angeles; Madison, Wis.; and California’s Santa Clara County.

“Green carts are a quick and nimble approach that can get fresh food out there relatively quickly,” says Rick Luftglass, executive director of the Laurie M. Tisch Illumination Fund, which has provided $2 million to support green carts in New York. “And because they are mobile, you can follow the need. If sales aren’t good on one block, you can move a few blocks away. It allows the market to build around the customers.”

Fruit-and-vegetable carts might seem like an idea that everyone can get behind in a city where some areas only have one supermarket per 60,000 residents. But New York’s Green Cart initiative was hotly debated here when it was proposed. City planners worried about congestion on the sidewalks and by busy subway stations. Small grocers objected to new, non-bricks-and-mortar competitors, especially those who didn’t have to pay high rents and utilities. But legislation ultimately passed in June 2008, granting up to 1,000 permits to vendors to sell fresh produce in underserved areas.

Nationally, much of the discussion about improving food access has centered on how to lure supermarkets back to urban areas. But New York’s Green Cart program has required significantly less time and investment than large and often controversial construction projects, says Karen Karp, president of Karp Resources, which provides education and training to green cart vendors. The program required no changes in zoning and no new bureaucracy. Potential vendors apply for permits through the same process as someone who wants to sell hot dogs or soft pretzels. And barriers to entry are low. On average it costs vendors about $3,000 to get up and running.

Generations of immigrants to New York got their start selling on the street. In the 19th century, the Lower East Side was full of pushcarts hawking pickles, flowers, buttons and hats. But today’s arrivals are limited by strict rules for sidewalk vending. There are multiyear waits to sell those New York hot dogs and a thriving black market for permits. (The history of immigrant street vending and the Green Cart program is charted in a new documentary, “The Apple Pushers,” also funded by the Tisch Illumination Fund.)

The Green Cart program, in contrast, offers a relatively easy way to get a business off the ground. But new vendors, who hail from countries including Ecuador, India, Mexico and Russia, have learned that simply setting up shop is not enough. Produce spoils quickly, and the profit margins are slim. One key to success for many vendors has been to accept federal food-assistance benefits. Bushwick vendor Victor, for example, estimates that his sales rose as much as 20 percent after he was given a wireless hand-held device to accept SNAP benefits, formerly known as food stamps.

“Before, people would buy something on special, maybe a bag of oranges for $2,” Victor said through a translator. “Now, they’ll spend between $8 and $11 using their benefits.”

Other cities are adapting New York’s model to fit their needs. Philadelphia, something of a pioneer of food-access programs, started its Healthy Carts as a pilot in 2011, with seven vendors. In an effort to capture foot traffic that New Yorkers take for granted, the carts were stationed near parks, playgrounds and other neighborhood destinations. But administrators noted that during the first year, the program’s most successful cart was one located inside the busy atrium at St. Christopher’s Hospital for Children in North Philadelphia. Hundreds of families pass through the lobby every day, and the indoor location allowed the vendor to stay open through the winter.

“The time cost to gain access to healthy foods is as important as the financial cost,” says Giridhar Mallya, the Philadelphia Department of Public Health’s director of policy and planning who is overseeing the Healthy Carts program. “So we’re looking at ways to serve people in places they are already coming or going. We think working with hospitals might be a way to scale the program and serve many folks of limited incomes.”

The District is still fine-tuning plans for its pilot program, which it hopes to launch in June. What is sure is that the five to seven carts will roll out on to the streets in Wards 5, 7 and 8, areas with the highest levels of obesity in the city and limited access to fresh food. (Ward 8, for example, was without any grocery store for nine years until, in 2007, Giant Food opened on Alabama Avenue SE.)

As in New York, the aim is to make fresh food more accessible and to create jobs, says Michele Tingling-Clemmons, bureau chief for nutrition and physical fitness programs at the Department of Health. But while new immigrants have applied for most of the green-cart licenses in New York, officials hope that in Washington the program will attract “nontraditional workers,” such as unemployed youth and seniors. “Here in D.C., we have a different population we want to help,” she says.

City officials say they are optimistic that by adapting New York’s model they can make fresh produce more accessible to consumers and more profitable for vendors. In the District, for example, city officials are hoping to offer food-handling licenses to vendors so they can sell fruit cups as well as whole fruits and chopped vegetables that can be bagged and sold as soup mix.

“We are all looking at a range of ways to provide healthy food. Carts are a small but important piece of that,” says Mallya of Philadelphia’s program. “We’re trying to make the healthy choice the easy choice.”

Black, a former Food section staffer now based in Brooklyn, writes Smarter Food monthly. Follow her on Twitter: @jane_black.