"It was as austere and as stern and unattractive as possible, and that was the whole idea of the architecture, too - to scare the wits out of you and persuade you that you didn't want to end up there," says Patsy McLaughlin, a longtime garden volunteer who lives on nearby Wallace Street.
After the prison closed in 1971, the lawn - and the rest of the 11-acre site, bounded by Fairmount Avenue and Brown Street, 22d Street and Corinthian Avenue - went straight to the devil. As did the interior.
Multiflora rose moved in, with junk trees and the detritus of city life - dead cats, empty beer bottles, corroded batteries, bags of trash.
"It was a terrible eyesore," recalls McLaughlin, who in 1976 planted a dozen roses out front to soften the weedy prison landscape. (Two survive.)
Today, the prison is a nonprofit museum that has undergone $10 million in stabilization and restoration work with more to come. The terrace garden costs about $2,900 in upkeep a year, most donated by the prison nonprofit.
The volunteers who take care of the garden are a hardy band that started big in 1990, four years before prison tours began. Their numbers have ebbed and flowed ever since, and they're mostly ebbing now. They're down to a dozen hard-cores like McLaughlin; the youngest is 50, and only a handful consistently show up for monthly work days.
Summer is critical. This is when everyone seems to be on vacation. It's also when the weeds go nuts and the sun is punishing. "At this time of year," Snell says, "I don't think of it as gardening. It's more like strategic weed-removal."
Dorene Martin, a retired school nurse who lives on 27th Street, has been a volunteer since the beginning, when the horticultural society wanted to "ring the city" with meadowlike strips of gold perennials and wildflowers. The prison was an early candidate for the program, called Ribbon of Gold, and the terrace garden still has golden yarrow, coreopsis, and asters.
But the scheme proved impractical. Typically, meadows need periodic mowing and burning, which was difficult in the first place and also illegal in the city.
Tending to all those perennials was tough, too. "Most of us were not sophisticated gardeners," Martin says, "so it was hard to tell what were plants and what were weeds."
By 1997, the meadow concept had given way to a mix of tough perennials, a few annuals for color, lower-maintenance trees and shrubs and - in response to the walls' being defaced with graffiti during the filming of the movie 12 Monkeys in 1995 - wall-climbing vines.
The garden's current habitat, wild and full, is quite a contrast to its original starkness, which sometimes worries Sally Elk, executive director of the nonprofit Eastern State Penitentiary Historic Site Inc.
"We love the garden because it's beautiful, but it's not portraying the historical use of the building," she says.
It's a distinction Snell understands, and it's why the landscape isn't wildly colorful. "We don't have a whole lot of pretty flowers. We don't want anything to take away from the hardness of this place," she says.
But a garden on the prison grounds is not out of character.
According to a 2004 cultural landscape study by landscape architects and planners Menke & Menke in Swarthmore, the prison from its earliest days had greenhouses, gardens, and landscaped pathways.
The warden and his family lived inside the walls, and enjoyed "a beautiful rose garden" attached to the house, according to landscape architect Bill Menke, who notes "photos from the 1920s show children playing in the garden with a rocking chair and toys strewn about."
Prison records indicate that inmates gardened in vegetable and flower beds, sometimes as a reward. They grew seedlings in the greenhouses to plant by the prisoner-processing center and other interior spaces, and also made money by selling greenhouse-grown flowers to guards on Mother's Day and Valentine's Day.
Over time, Menke says, "as more and more buildings appeared inside the prison, there was less and less landscape." Only one greenhouse survives, and in 2005 its $18,000 restoration was completed.
It's now part of the prison tour, which draws 130,000 visitors a year.
Waiting in line along Fairmount Avenue, those visitors may not even notice the terrace garden looming behind them. But it's worth a look.
In early August, the purple buddleias are fuzzy with bees and butterflies; the cranberry viburnums are heavy with beady red fruits. Interspersed are perennial stands and billowy clumps of ornamental grasses, some spiking 15 feet above the sidewalk.
Against these 30-foot walls, the garden's scale feels right. So does the look, which in the height of summer is overwhelmingly green, with an occasional pop of pink.
In that spirit, the prison's near-complete master plan will not call for additional, or more colorful, landscaping, Elk says.
She's far more concerned about visitor services - how guests are greeted, assembled, and ticketed. "That, and toilets, is our top priority," she says.
Read gardening writer Virginia A. Smith's blog at www.philly.com/philly/blogs/
Volunteer workdays are held at the terrace garden at Eastern State Penitentiary on the second Saturday of the month, 9 a.m. to noon, through fall.
Next work day: Aug. 13.
No gardening experience is necessary; novices will be paired with veterans. Julie Snell, with the Pennsylvania Horticultural Society, brings tools, snacks, and the to-do list. She suggests volunteers wear long pants, closed shoes, gloves, and hat. Bring sunscreen.
Contact Snell at jsnell@Pennhort.org or go to www.phsonline.org; search for volunteer opportunities, then public landscapes. For more on Eastern State Penitentiary, go to www.easternstate.org/.
Julie Snell talks about the work of the garden volunteers at
Contact garden writer Virginia A. Smith at 215-854-5720 or email@example.com.