One Saturday morning in late April, East London’s Spitalfields City Farm was all abuzz. Sitting on 1.3 acres once occupied by a railway depot, it’s one of dozens of urban agriculture operations tucked into the cramped cityscape that straddles the Thames River between Tower Bridge and the Prime Meridian.

Trains rushing between Shoreditch High Street and Whitechapel stations ruffled the petals of blooming apple trees. Trowels clinked into compost-enriched soil in raised-bed allotments. A call to midday prayer from Brick Lane’s Jamme Masjid (mosque) and Happy Birthday rising from the party pavilion mingled with the cock-a-doodle-doo of a confused rooster.

These sounds (and the farm cafe offering salad made from greens grown on site) made my local food lover’s heart happy. But then my skeptical journalist’s brain kicked in. Can spaces like these actually make a dent in this neighborhood’s daily food requirements? Are any of the estimated 50,000 annual visitors soaking up the whys and hows of the local food movement, or are they just in it for a lovely day out getting a farmyard fix?

I started digging for answers. The data is spotty, at best.

Apple trees in bloom at Spitalfields City Farm in London. Photo by Christine Burns Rudalevige

Capital Growth is a nonprofit organization that offers in-kind support to more than 2,000 Londoners who grow their own food at home or in allotments on sites like Spitalfields City Farm. In 2013, Capital Growth launched a Harvest-O-Meter tool to quantify how much food its membership grows. That year, 189 members reported growing 18,500 kg (about 40,000 pounds) of produce worth about 288,000 British pounds sterling ($366,495).

Ten years later, Capital Growth’s membership has ballooned to 2,000, but only 10 percent of growers use the reporting tool, coordinator Rachel Dring said. That small fraction reported growing 3900 kg (about 8,600 pounds) of produce in 2023. Given the varying size of the gardens, allotments and farms, it’s difficult to extrapolate from that data the size of the total harvest, and it would be fruitless to compare the most recent harvest to the 2013 numbers.

Data on urban agriculture production in the United States is equally spotty, said Ramon Borges-Mendez, a professor of urban planning and community development at Clark University in Worcester, Massachusetts. Borges-Mendez is involved in the Feeding New England project, which has a goal of the region producing 30% of the food it consumes.

Small-scale surveys have been done in American cities like Detroit, New York, Philadelphia and Pasadena, he said, places where urban agriculture thrives. But he knows of no study that measures how much food that urban agriculture contributes to the national system. “It’s just too small of a contribution at this point,” Borges-Mendez said. (On the positive side, plenty of room for growth.)

Carrick Gambell, an urban agriculture professional who holds a joint position with the USDA Natural Resources Conservation Service and UMaine Cooperative Extension in Scarborough, says the USDA definition of “urban agriculture” is purposely vague so that more rural states like Maine can tap into a pool of federal grants. Basically, if food is grown on land that was previously developed, the effort can be classified as urban agriculture. Locally, the definition includes such diverse projects as the Biddeford Middle School Garden Project, Backyard Blooms flower farm in Woodford’s Corner in Portland, and the gardens at Maine’s prisons, as well as more commercial ventures like Vertical Harvest’s 68-foot-high hydroponic garden in Westbrook.

Cultivating Community in Portland is one of the most established urban agriculture operations in the state; it manages 11 community gardens and other open harvest sites where anyone is welcome to pick the produce. In all, the organization oversees 4.7 acres of city land consisting of about 450 community garden plots. Executive Director Silvan Shawe says 500 people are on the waiting list for plots in Portland; the organization’s five-year goal is to more than double the number of allotments it supports, to 1,000.

Three factors inhibit the growth of urban agriculture, Borges-Mendez said: pressure on cities to provide more affordable housing, contaminated soil at many industrial urban sites (it’s very expensive to remediate), and the lack of people with time and expertise to manage season-extending greenhouses.

London is a case in point. Because public parks have always been valued by the public and supported by the monarchy and the government, the city has historically had a lot of greenspace. But – much like an uncovered cake sitting on the kitchen counter – persistent development pressure driven by the public housing crisis is nibbling away at its greenspace, according to John Sadler, a London-based officer of CPRE (an organization like the USDA’s Natural Resources Conservation Service),

Goats wait in line to make a call at London’s Spitalfields City Farm. OK, fine, they’re just hanging out. Photo by Christine Burns Rudalevige

Borges-Mendez, who also sits on Worcester’s community development commission, says that in American cities, new housing units almost always win out over space for community gardening. The lack of hard numbers to quantify how much these gardens contribute to the food system makes it harder to defend them, he said. Both Sadler and Borges-Mendes advise community gardeners and urban farmers to monitor future threats to urban agriculture spaces and to work with local officials to build cases to protect them as designated sites for natural, cultural or community importance.

A prime example of just that is a recent action undertaken by organizers of the Mount Joy Community Orchard in Portland when they realized that the proposed redevelopment of an adjacent lot might throw the orchard’s heritage apple, pear, peach, cherry and paw paw trees into shadow. The group used a simulation tool to determine when and how much shade the proposed building would cast. After they determined the building would not adversely affect the trees’ fruit production, after all, organizers withdrew their opposition to the zoning variance needed to allow the building.

But they added a few caveats: First, that 25-35 percent of the building’s housing units be affordable. Second, that no trees are damaged during construction. And third, that the proposed building’s windows be made of bird-safe glass.

Although it’s not easy to get hard numbers, no one questions the educational and cultural value of urban gardens. Cultivating Communities, for instance, provides hands-on outdoor education to Portland’s 3,000 elementary students, offers paid farming internships to high school students, and runs the New American Sustainable Agriculture Project, which provides new immigrant, refugee and asylum-seeking farmers with access to land, training, and market support.

“Not only do they show the potential to grow a lot of food in very tight spaces, they clearly demonstrate that growing food in an urban setting, because it connects you to your community, is also cultural nourishment,” Gambell said.

Carrot, Curry and Chili Scotch Eggs with Chutney.  Photo by Christine Burns Rudalevige

Carrot, Curry and Chili Scotch Eggs

Traditional scotch eggs, first made popular as a portable snack at the Fortnum & Mason department store in London in the mid-1700, are hard-boiled and coated in sausage and breadcrumb shell. I found this veggie version in “Wasted,” a cookbook by Conor Spacey, a British sustainable food advocate. The book emphasizes buying local food and not wasting a morsel of it.

Makes 4 Scotch eggs

6 large eggs
1 tablespoon canola oil, plus more for frying
1/4 cup very finely chopped onion
1 clove garlic, finely chopped
2/3 cup finely grated raw carrot
2 fresh red chilies (like Fresno for mild heat, serrano for medium heat, Birdseye for a lot of heat)
2 tablespoons curry paste
2/3 cups breadcrumbs, divided
2 tablespoons finely chopped cilantro leaves
1/4 cup all-purpose flour
Your favorite chutney, for serving

Fill a bowl with ice and add cold water.

Bring a pot of water to a boil. Using a spoon, gently place 4 of the eggs, 1 at a time, into the pot. Bring the water back to a boil and cook for 6 minutes for a jammy center, or 9 minutes for a hard-boiled center. Immediately, transfer the cooked eggs to the ice bath. When they are totally cooled, peel the eggs and set aside. Compost the shells.

Warm a tablespoon of oil in a medium skillet over medium heat. Add the onion and garlic and cook gently until soft, about 4 minutes. Add the carrots and chilies and cook until soft, about 5 minutes more. Stir in the curry paste and cook for 2 minutes to release its flavors. Transfer the mixture to a large bowl. Add 1/3 cup breadcrumbs and mix thoroughly. Season the mixture with salt and pepper and let it cool to room temperature. Beat 1 of the remaining raw eggs with a fork and add it to the carrot mixture. Combine to form a paste.

With wet hands, divide the mixture into 4 portions. Use your wet hands to form a round patty with 1 of the portions. Place 1 of the boiled eggs in the center and wrap the mixture around it until the egg is fully covered. Repeat with the remaining portions. Let the coated eggs set in the refrigerator for at least an hour.

Put the flour in 1 small bowl, beat the last raw egg in a second small bowl, and combine the remaining 1/3 cup breadcrumbs and chopped cilantro in a third small bowl. Working with 1 boiled and coated egg at a time, roll it first in flour, then in beaten raw egg, and then in the breadcrumbs. Let the doubly coated eggs set for 30 minutes in the refrigerator.

In a medium saucepan, warm 2 inches of canola oil to 350 degrees over medium-high heat. Gently place the scotch eggs in the oil and cook, turning them as needed, until they are golden all the way around, 4-5 minutes. Let the fried Scotch eggs drain on a repurposed paper bag for a couple of minutes.

Serve warm with your favorite chutney.

Local foods advocate Christine Burns Rudalevige is the former editor of Edible Maine magazine and the author of “Green Plate Special,” both a column about eating sustainably in the Portland Press Herald and the name of her 2017 cookbook. She can be contacted at: cburns1227@gmail.com.