Window boxes, decorative plants and ginkgo trees adorn many of the street-facing homes between 20th and 22nd and Kater and Lombard in Philadelphia’s Southwest Center City neighborhood.

It takes only one person to plant a sunflower in a window box and the rest of the block will do something similar, said Daniel Marut, who lives on Kater Street.

Marut co-tends a backyard garden with two of his neighbors. His courtyard is full of bamboo to provide shade, which helps such plants as astilbe — a perennial flower with fern-like foliage and a gift from his wife’s mother — to flourish.

When a neighbor cleaned up the back alley, which had been blocked for years by debris, Marut saw the opportunity to link the two yards and collaborate on the gardening.

“He started hacking through the mess, and the moment that he connected, that’s when I was inspired to extend our garden even further and put in the patio bricks into the back alley,” Marut said. “I was excited and immediately saw the potential for putting in and growing a little community back there.”

A landscape engineer, Marut, 43, focused on designing gardens and building walkways across the yards. The work was familiar, because he spent his teenage summers digging holes for garden installations, mowing lawns, and installing brick walkways and patios.

Later, at Drexel University, he minored in architecture.

“One of the ideas of architecture is to create space, and landscaping is basically about creating outdoor space,” said Marut, whose love of plants and gardening came from his mother. “Witnessing how you can transform an outdoor space of a back alley from nothing, you create space from a rooftop to a rooftop garden. I’ve seen that transformation take place and it’s exciting.”

So when Marut found the opportunity to work on the alley garden with neighbors — whom he had never met — he seized it.

They planted tomatoes, cucumbers, strawberries, sage, lemon balm, basil, and some other herbs. They also make their own compost to nourish the plants. They share the harvest, which is sometimes plentiful.

Neighborhood gardening is quite common in the city. With space being an issue in many neighborhoods, residents start gardening as a group, said Sally McCabe, associate director of community education at the Pennsylvania Horticultural Society (PHS) in Philadelphia.

“If you have a block where everybody has plants in front of their house, you know that it’s going to be a beautiful block and probably a safer block,” McCabe said. With people maintaining their plants, there are more “eyes on the street.”

Marut has been living and gardening in the neighborhood for close to 17 years, but he wasn’t the first gardener. That distinction goes to Betsy Alexander, 62, who has lived on Naudain Street for 20 years.

Alexander is known in the neighborhood for the large pots filled with tall plants that form a garden the width of her rowhouse. She designed grape vines to run through her top doorpost and around the house through the back.

“Gardening is contagious,” she said. “If you put in a garden, then other people start gardening. It always happens, and it’s definitely happened here.”

Some of the houses around Alexander were vacant when she moved to the neighborhood, and that worked to her advantage, she said. She placed potted plants in front of the empty homes, where she planted grapevines, passion flowers and evergreens, creating an illusion to outsiders that people resided in the houses. When people moved in, they liked her plantings and kept them. Some even expanded the gardens.

The apartments landlord even sent her a thank-you note. “He was so excited that the plants were growing there that he talked to people till he found me and then sent me a thank-you note,” she said. “He told me that he hired a gardener to garden the front of his building after seeing what happened here.”

Gardening doesn’t only benefit the neighborhood; it helps the environment, Marut said. Plants help purify the atmosphere by releasing oxygen. People help the plants by providing carbon dioxide, Marut said.

Keeping gardens also helps create habitat for wildlife, Marut said. Soil attracts some insects, bugs and spiders, which, in turn, serve as food for birds. “We get all sorts of birds,” he said, chuckling. “It creates an ecosystem in a city that wouldn’t exist.”

Marut also has a rooftop garden where he has pots of tomatoes, basil, mint and a lily plant from his mother’s gardens. In addition to that, he was inspired by the Philadelphia Water Department’s Rain Check program to build a rain garden, which traps water and filters soil. Rain gardens help keep oil, grease and debris out of Philadelphia’s sewage systems and rivers.

With the country’s rampant political division, Alexander finds unifying solace in gardening. “One thing that’s obvious to me is that no matter who you voted for, everybody loves a garden.” she said. “It’s a very unifying, positive experience.”