The National Wildlife Federation

Donate Donate

Empty Lots ... of Opportunity

Communities are turning unused land into green havens that nurture both wildlife and people.

  • Janet Marinelli
  • Conservation
  • Apr 01, 2021

Beloved Philadelphia native son and longtime 60 Minutes correspondent Ed Bradley gazes warmly from a mural in front of a pollinator garden—one of 50 such gardens installed in two city neighborhoods in 2019. Its vivid flowers and benches make it a welcome oasis for neighbors. (Mural Design by Ernel Martinez, Photo by Samir Dalal)

AMINATA SANDRA CALHOUN SAYS HER CHILDHOOD neighborhood in West Philadelphia was once so beautiful “you could put it on the cover of Good Housekeeping.” When she moved back to her late parents’ home after 40 years, however, the streets were strewn with trash. Blocks once lined with stately old trees were bare. “Whoever cut down those trees,” she says, “had taken the life out of the community.”

For well over a year, Calhoun inundated her local officials with letters and emails complaining about two collapsed houses down the block, at the corner of Belmont and Wyalusing Avenues, one of which had been a doctor’s office when she was growing up. One windy December day, as she walked by the huge heap of weed-choked debris, a brick came tumbling down, narrowly missing her head. Calhoun threatened to take legal action, and within 48 hours, city workers had begun to remove the pile of rubble.

“I had been thinking about how to awaken the community,” says Calhoun. “Restore community pride. Dignity. Environmental justice.” The former art gallery owner, known to wear vivid teal lipstick and bold glasses, resolved to have an inspirational mural painted on the massive wall that remained when the lot was cleared. In June 2018, neighbors gathered for a rousing dedication of the rowhouse-high mural honoring local hero Ed Bradley, a West Philly native and broadcast legend who was a correspondent on 60 Minutes for 25 years.

“The next step,” Calhoun recalls saying to herself, “is to beautify the lot.” Last summer, that vision became reality when purple and yellow coneflowers and pink blazing stars began blooming in front of Bradley’s image—one of 50 gardens planted in two Philadelphia neighborhoods the previous fall. The gardens were installed through a pilot program—launched by the Pennsylvania Horticultural Society (PHS) and the National Wildlife Federation with a grant from the Wildlife Conservation Society—to transform vacant lots by planting flower-filled, climate-resilient gardens that provide habitat for pollinators.

“By creating these pollinator gardens, we’re not only benefiting the environment, we’re investing in communities that traditionally have not been invested in,” says Natalie Cohen, conservation programs coordinator for NWF’s Mid-Atlantic Regional Center. “Unfortunately, there are a lot of vacant lots across the country,” adds Holly Gallagher, the Federation’s senior manager of education and community conservation, “but that also means there are a lot of opportunities to enhance urban conservation and public health.”

Read the Caption
A group of people planting in a lot in Philedelphia

In fall 2019, landscape contractors designed new gardens (below), then supplied (bottom) and planted (above) butterfly weed, prairie dropseed and other native species—a total of 15,000 individual plants—in former empty lots in Philadelphia. Beyond bringing new life to once-vacant sites, the program, launched by the Pennsylvania Horticultural Society and the National Wildlife Federation, created an “ideal plant palette of native species” that can be grown in other cities with similar climates.

Rich with possibility

According to a 2016 paper published in the Journal of Urban Design, an average of nearly 17 percent of the land in large U.S. cities is vacant, particularly in older, postindustrial cities with high levels of poverty such as Philadelphia and Detroit. Researchers have calculated that if every square block of this abandoned land were placed side-by-side, the area would be larger than the country of Switzerland.

A person holding a piece of paper with a garden plan on it

Sagar Shah, manager of planning and community health at the American Planning Association, expects the amount of vacant land in cities to increase exponentially in the next 10 to 15 years as COVID-19 accelerates the work-at-home trend. For example, he says, “there will be a lot of parking spaces downtown and no use for them.”

These empty spaces represent opportunities both for wildlife and people. According to Shah, “people living in historically underinvested communities don’t have access to nature.” If vacant lot restoration were done on a large scale, he says, it could enhance environmental equity by providing access to green spaces. 

In Philadelphia, the LandCare program, run by PHS, is considered a model for transforming vacant lots into community assets. Launched in 2001, the program today encompasses more than 12,000 lots covering more than 16 million square feet of land in low- and moderate-income neighborhoods. “We focus on areas that are near schools, have families nearby and are located along commercial corridors where people walk,” says LandCare’s planning manager, Samir Dalal. He adds that sites with strong community advocates such as Calhoun are ideal.

A man handing another man a tray of plants

PHS hires local contractors to clean out the lots, plant grass and then maintain the spaces by mowing regularly. Research has shown that these cleaned and greened lots have been a boon to the health of people who live close to them. A 2018 study published in the journal JAMA Network Open, for example, found that feelings of depression fell by more than 40 percent among nearby residents. Another paper documented a 29 percent drop in gun violence in neighborhoods that have LandCare lots.

But could the lots provide even more benefits? When NWF staff toured the LandCare sites a few years ago, they realized they could help increase the lots’ ecological and social value. Building on a project in Baltimore—where NWF worked with local partners to turn a vacant lot into a nature-based playground with native plants, murals and a rain garden—the Mid-Atlantic team joined with PHS to have some 15,000 plants installed in the 50 Philadelphia sites. As in Baltimore, the gardens are designed not only to enhance city neighborhoods but also to soak up torrential rains projected to become more common with climate change, mitigate heat waves (because plants release cooling water vapor when they transpire) and provide habitat for pollinators, birds and other wildlife.

Read the Caption
A pollinator garden in front of a colorful mural

This touching mural titled “A Tribute to Alex Scott” honors a little girl whose lemonade stand raised funds to benefit children like her with cancer. Next to the mural, one of Philadelphia’s new pollinator gardens blooms with native plants that benefit bees and butterflies—and soothe the souls of those who come to enjoy the beauty of nature.

Enriching biodiversity

“People often think of urban areas as biological deserts,” says Cohen. “But cities and suburbs are home to nearly two-thirds of all wildlife species in North America.” Research suggests that urban land that is now vacant has the potential to provide habitat for a wide range of plants, birds and insects, even endangered species. In fact, a number of studies have found that cities are refuges for insect pollinators and harbor a surprisingly high diversity and abundance of bees, in some cases higher than in rural or natural areas. What’s more, vacant lots can act as wildlife corridors—stepping-stones for animals to move between parks and other, larger green spaces, amplifying their habitat benefits.

One goal of the Philadelphia program, says Gallagher, has been to work with University of Maryland–Baltimore County ecologist Chris Swan “to determine the ideal plant palette of native species” to grow on LandCare lots. She says the list will also be distributed to landscape architects, city planners and other municipal officials so the plantings can be replicated in other cities with similar climates. “My research in Baltimore has shown that you can get native plant species to grow in these harsh environments on their own, which is a surprise because you don’t see them there,” says Swan. “The reason you don’t see them there is because they can’t get there, but if you plant them, they do fine.”

Swan provided the Philadelphia team with a list of two dozen city-tested native species. From this list, 13 species were chosen, including orange butterfly weed, purple and yellow coneflowers, aromatic aster, rough-stemmed goldenrod, prairie dropseed and bee balm. The 15,000 plants were assembled in groups of four, six, eight, 10 or 12 species, then located randomly in the 50 300-square-foot gardens.

Swan notes that the Philadelphia gardens were designed to be more successful than his Baltimore test plots. “In Baltimore,” he says, “I cast seeds, and in Philadelphia, they used plugs” (young plants grown in trays, which are sturdier than germinated seedlings). “There was also soil prep.” In fall 2019, local landscaping contractors loosened the compacted city soil and added a 50/50 mix of compost and topsoil. To get the plants off to a good start, they watered and mulched once the plugs were planted. Local landscaping companies also maintained the plantings beginning the following spring by watering, weeding and edging the perimeter of the gardens every two weeks. Swan and his colleagues took an inventory of the plants that persisted and those that perished. To get a sense of the vigor of those that survived, they measured plant height and also assessed soil moisture.

Though Swan feared some species would “run out of gas by the end of the season,” the results surpassed his hopes. The coneflowers, blazing star, butterfly weed, aster and goldenrod did particularly well. Only one species, prairie dropseed, performed poorly, while salvia and bee balm had varying survival rates. Moisture levels were lower in the planting beds than in adjacent compacted soil, suggesting that the plants and loosened soil are taking up more water than the surrounding turf—a good sign that they will be able to help reduce runoff and flooding.

Swan believes that maintenance was the key to the gardens’ success. “You’ve got to go in and weed them and keep them from being overrun” by the nonnative weeds typically found on urban sites until the natives can fend for themselves, he says. And because they were grown from plugs instead of seeds, the plants had a jump start. Swan expects they will be self-sustaining in just a couple of years.

Gallagher and Cohen hope volunteers will be able to begin monitoring pollinator activity at the sites this summer. By installing gardens close enough together that pollinators can travel from one to another, Dalal says he hopes eventually to create a habitat corridor stretching more than 12 miles from John Heinz National Wildlife Refuge in southwest Philadelphia north to historic Bartram’s Garden on the Schuylkill River and the Philadelphia Zoo.

Meanwhile, the existing gardens have been a big hit among members of the community. Calhoun says her neighbors love their garden. “It’s no longer a lot,” she says. “It’s the Ed Bradley community oasis.”


New York City-based Janet Marinelli is a regular contributor.


More from National Wildlife magazine and the National Wildlife Federation:

When Cities Welcome Wildlife »
Urban Greening: Bloom or Bust »
NWF Blog: Vacant Lots to Pollinator Habitat in Philadelphia, PA »

Get Involved

Where We Work

More than one-third of U.S. fish and wildlife species are at risk of extinction in the coming decades. We're on the ground in seven regions across the country, collaborating with 53 state and territory affiliates to reverse the crisis and ensure wildlife thrive.

Learn More
Regional Centers and Affiliates
X
Celebrate Garden for Wildlife Month