Freshly dug carrots (John McDonnell/THE WASHINGTON POST)

Hand-wringing over the ills of public education has been a national pastime for a long while, but it’s hard to think of many, if any, downsides to the school garden movement.

Once used to teach vocational secondary students horticultural skills (still a worthy endeavor, by the way), the school garden vanished for decades and has since reemerged wholly reinvented and invigorated. Today it serves a far more complicated and enriching role that includes connecting younger children to nature, to nutritious food and to the wonder and science of the plant and animal kingdoms.

For thousands of local grade-schoolers, the gardens have brought a direct link between growing and eating food, a simple but profound formative revelation that, for the most part, was denied the parents of these children, and even their parents.

“Everyone is taught to think of food as a burden,” said Jennifer Mampara, the school-garden and nutrition teacher at Watkins Elementary School on Capitol Hill. “The kids here enjoy making food, and they really enjoy eating what they make.”

I have been somewhat skeptical of school vegetable gardens: First, I wondered who would be around to shepherd and harvest the main season crops of tomatoes, peppers, cucumbers, okra, squash, corn, melons — all the bounty of July and August when the classrooms are empty.

Second, and moreover, who would maintain a veggie garden, which needs periodic major soil work and construction and then continuous attention and toil, with tying, pruning, thinning, weeding, watering and harvesting?

With now more than 80 school gardens in the District, a city law to promote school gardens and a citywide garden coordinator,, the early logistical issues seem to have been addressed.

Aided by a long growing season in our region, the gardeners have learned to align vegetable sowing and harvesting with the academic year. This might be something as simple as growing varieties of shelling beans instead of green beans, to be collected by willing little hands when the pods are shriveled in October.

The second problem has been addressed with the recognition that you cannot build a garden and then rely on the teachers and enthusiastic parents alone to keep it going. You need a person who will organize the maintenance and work with teachers to provide links between classes and garden.

You also need extra money, and for the most successful gardens, that has meant finding a nonprofit to provide grants for building gardens and to fund positions, typically part time, to pull it together.

Watkins was one of the first schools in the District to have a garden, the first in 1994 as a verdant outdoor classroom themed around primeval plants and dinosaurs and expanded to include a wildlife and native plant garden.

Three sides of the building are now wrapped in gardens; on the west side a wetland garden functions as a lesson in Chesapeake Bay ecology.

Volunteer garden coordinator Barbara Percival spends most of her time, however, in the extensive, fenced vegetable garden on the south side of the school, which stretches almost 90 feet along E Street SE. The garden has 23 raised beds, and the fence functions as a long and willing trellis. Awaiting the arrival of the children next week, the garden is designed to hit its stride in September and October. In adjacent beds, the children will harvest an anticipated 100 pounds of sweet potatoes around Thanksgiving from slips they rooted in May.

As with their counterparts in other school gardens, Percival and Mampara are waiting until late August to start seeds of fall crops that otherwise might have been sown earlier in the month, so the children can get their hands dirty.

Fifteen classes in the first, third and fourth grades meet in the garden, as well as in a converted food lab in the school.

“The kids are very excited to do anything in the garden,” said Mampara. “There’s something to be said for education that brings so much joy.” Mampara’s position and much of the costs of the vegetable garden and food lab have been funded by the nonprofit Freshfarm Markets.

Across town at Stoddert Elementary School in Glover Park, the school garden occupies about 4,000 square feet at the edge of a ball field and serves as a model for its various components, said Sam Ullery, the school system’s school garden specialist. “I love this garden because it has all the elements we want,” he said, surveying the site. Picnic tables and pint-sized benches are arranged in the shade of two old walnut trees. The sunnier areas contain a butterfly garden, an area of American Indian crops and the vegetable and herb garden proper, growing out of six raised beds. Framed in split-rail fencing (soon to support espaliered fruit trees), the space also includes a storage shed and a greenhouse where garden coordinator Kealy Rudersdorf is preparing to start seeds as part of classroom lessons. The garden is two years old, but Rudersdorf started last winter after a stint at an organic cacao farm in Costa Rica. She also has a master’s degree in education.

“The more you have out here, the more you can inspire the teachers” to work the garden into lesson plans, said Sarah Bernardi, director of programs at D.C. Greens, Stoddert’s sponsoring nonprofit.

The gardens offer obvious contexts for botany, ecology and agriculture, but they also serve as laboratories for math, social studies, language, soil science, art, genetics — the list is almost endless to a creative teacher.

Rudimentary at the elementary level, the gardens provide high-schoolers a starker link between the source of food and its quality and nutrition at a time when our food norms are seriously out of kilter. At the Thurgood Marshall Academy, a small, public charter high school in Anacostia, a large fruit and vegetable garden serves as a pleasant green space for its students and a place to learn for members of the school’s garden club. Seven students worked in the garden over the summer. Its chief sponsor was Earth Day Network.

“With young kids it’s much more exploratory and sensational,” said Kate Lee, the part-time garden coordinator. “With the older kids it’s more a frame of reference: How does this relate to our culture and our community?”

Urban food deserts are seen as a contributor to poor diet and a factor in obesity rates that are higher among African Americans.

But even in the agricultural heartland, generations of children have lost a connection to the story of their food.

“I grew up in Nebraska, and my mom always had a garden in the back yard, but I didn’t know what was going on,” Rudersdorf said. “I wish I had something like this. I think it’s a great learning opportunity.”

School gardens, now as fruitful as the late summer harvest, should be viewed as not only viable but indispensable.

Perhaps no previous generation of schoolchildren required them more: With climate change and other ecological crises, kids today need a grounding in the environment. On a personal level, they need to understand that fresh food means a good diet.

In the fourth-floor food lab at Watkins, Mampara said that “a lot of people compare what we are doing here to home economics. It is so far from that. This is hugely important in their understanding of what food is, where it comes from and what it means to eat well.”

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Read past columns by Higgins.