WHITE PLAINS, N.Y. >> The youngsters were bent over, pulling out some of the more spindly turnips to make room for the fatter ones to grow even bigger. Their small farm on the 77-acre campus of New York School for the Deaf here was a way not only to help them learn about photosynthesis and plant cycles, but also to help feed the hungry in Westchester County.

Westchester is among the wealthiest counties in the country, but there are nonetheless 200,000 residents at risk of hunger. This farm is one of five sites scattered across the county that provide fresh produce for the Food Bank for Westchester, which distributed 7.6 million pounds of food in its last fiscal year.

The students "are developing work skills and learning about the science of gardening, but they are also giving back to people," said Ron Stern, the school’s superintendent, who communicated through a sign language interpreter.

For officials at the food bank, including locally grown fruits and vegetables in the mix of frozen, canned and dry food is a priority, as many of their clients are using the food bank for continued sustenance, not as a stopgap measure.

"It’s become more and more important to change the kind of food we provide," said Ellen Lynch, president of the food bank, which began harvesting food several years ago. "You can live on rice and beans and stuff that comes out of a can. But when you are talking about children and seniors, it’s not sustainable. So more emphasis is being placed on fresh food and nutritious food."

Westchester is not alone. Across upstate New York, where agriculture is still a mainstay of the economy, more and more food banks are growing their own produce. The Food Bank of WNY, in western New York, has made nearly two dozen garden beds available to volunteer groups who can cultivate the land to feed the hungry. And the Regional Food Bank of Northeastern New York grows up to 200,000 pounds of fresh produce a year.

In Westchester, where agriculture long ago gave way to bedroom communities and corporate office parks, the food bank has a greater challenge in identifying available land. But it now produces 9,200 pounds of produce annually on land belonging to institutions and groups like School for the Deaf, the county’s juvenile detention center and the Westchester Land Trust.

Overseeing that effort is Douglass DeCandia, the food bank’s growing program coordinator. Driving from site to site in his faded Subaru (with a "No Farms, No Food" bumper sticker), he works with students, corporate volunteers and juvenile offenders to coax eggplants, tomatoes, kale, potatoes, chili peppers, beans and Swiss chard from the land.

At Woodfield Cottage, the maximum-security juvenile detention center in Valhalla, he can work with only one person at a time.

"That one-to-one is really good because it’s much more intimate," said DeCandia, 29, who studied sustainable agriculture in college. He recently harvested perfectly round eggplants and bright-red hot peppers from the one-acre plot at Woodfield, which is hemmed in by a tall, black security fence.

At School for the Deaf, by contrast, groups of students work together in the 3/4-acre field, which produces 3,000 pounds of food a year. DeCandia has made a point of cultivating heirloom varieties of vegetables, like red, yellow, purple and sweet potatoes.

"There are hundreds of varieties of potatoes, but we’ve gotten so used to seeing just white potatoes," he said. "In that variety are all the vitamins and nutrients."

Stern, the school superintendent, quipped: "We don’t grow couch potatoes here."

Indeed, Justin Van Dunk, a 16-year-old student, was crouched over the turnip bed.

"You get the whole root," he said, as he thinned the crop with his classmates. "If they’re too crowded, they are stuck in the ground."

One challenge for the food bank is prodding residents to try vegetables they may never have seen. The food bank has 160 partners, such as churches, YMCAs and other groups, to help distribute the food. And it employs two nutritionists who come up with recipes for chard, kale and other vegetables that are made available at the distribution sites.

Students at School for the Deaf are also learning about less familiar herbs and vegetables, from Jerusalem artichokes — a species of sunflower that resembles small potatoes — to comfrey, a perennial herb that can be used to make tea and herbal remedies. Some of the flowers and herbs are grown to attract honey bees, since the food bank cannot keep bees at the farm sites.

While almost all of the produce goes straight to the food bank, some is kept for the school’s staff cafe.

"This allows the students to make an association between what they see at the supermarket and what comes from the earth," said Carol Rapport-Sommer, director of special programs and services at School for the Deaf, where the garden is now in its third season. "It’s multi-sensory learning."

© 2015 The New York Times Company