The seemingly vacant lot on Philadelphia’s South Street looks like it’s being eaten by the city. Instead of grass and weeds, bits of urban detritus nibble at the chain-link fence and creep up the adjacent walls, forming odd and intriguing designs.

The lot, it turns out, isn’t vacant at all. Adjacent to the studio of artist Isaiah Zagar, sixty-five, it is the centrepiece of the dozens of murals and other pieces of art that Zagar has installed within an eleven-block radius of his workshop. Far from being the kind of cloyingly cheerful, civic-sponsored murals that dot the American inner-city landscape, Zagar’s work is weird and whimsical, making use of any number of found objects. Colour and texture fill blank walls; smiling faces emerge from Gaudiesque mosaics and keep watchful eyes on the street. Dead space is repopulated with strange new characters.

In 1987, when Zagar opened his studio, the lot was home to rats and vagrants. “Totally uncared for,” clucked Allison Weiss, Zagar’s busy-sounding assistant, on a recent afternoon. In 1994, with the consent of the lot owner’s realtor, Sam Orocofsky, Zagar set to work transforming the property into a verdant collection of sculptures and murals. Within full view of one of Philadelphia’s busiest pedestrian streets, the lot is frequented around the clock by locals and even busloads of tourists. Now, says Weiss, “it’s a destination.” Zagar calls it his “magic garden.”

But in a matter of days the magic garden could meet an untimely death. In early May, Orocofsky gave Zagar two weeks to get rid of the art. The lot is for sale, explained the realtor, and prospective buyers need a clear view, unobstructed by sculptures and fences decorated with old bicycle wheels.

Zagar and neighbourhood residents were stunned. Purchased by a Boston real estate trust in 1988 for $130,000, the lot is now selling for $300,000. Unable to buy the lot on his own--most of his public art is created gratis--Zagar turned to the community. The response has been extraordinary. When I spoke to Weiss, a petition to save the lot had in just two days amassed more than five hundred signatures. The local congressman’s office wrote a letter to the owner, pleading that the sale be reconsidered. A city councilman pledged his support, although Weiss says cuts to arts funding have limited the city’s room to manoeuvre. Since news broke of the garden’s pending deconstruction, more than a thousand dollars has been raised, and the Philadelphia Volunteer Lawyers for the Arts has offered its support. Zagar and his supporters have obtained a temporary restraining order on the May 23 deadline and are hoping for a ninety-day extension.

For his part, Orocofsky points out that the lot has been on the market for a long time, with Zagar’s knowledge. And, after all, it is perfectly within the owner’s right to sell his property. Even the neglect of the lot--leaving it in a derelict state for such a long time--can be rationalized: the trust that owns the lot has paid its fair share of property taxes. Still, cities are so much more than mere collections of private property. They are living creatures, human-made ecosystems that are as hurt by decrepit vacant lots as they are helped by creations like Zagar’s art.

I’m reminded of something the eminent urban theorist Jane Jacobs said recently while promoting her new book in New York. Explaining the difference between her vision of the city and that of the planners she fought against in the 1950s and ’60s, she told a reporter, “New York still has so much pizzazz, because people make it new every day. Like all cities, it’s self-organizing. People looking for a date on Third Avenue make it into a place full of hope and expectation, and this has nothing to do with architecture. Those are the emotions that draw us to cities, and they depend on things being a bit messy. The most perfectly designed place can’t compete. Everything is provided, which is the worst thing we can provide.”

“There’s a joke,” Jacobs continued, “about a preacher who warns children, ‘In Hell there will be wailing and weeping and gnashing of teeth.’ ‘What if you don’t have teeth?’ one of the children asks. ‘Then teeth will be provided,’ the preacher says sternly. That’s it, the spirit of the designed city: Teeth Will Be Provided for You.”

Her point sums up what’s at stake with Zagar’s magic garden: messiness and intangibility face off against firm deadlines and heartless commercial interests. For years, Zagar’s work has revived the dull, dead corners of Philadelphia. His garden is the kind of spontaneous expression of creativity that makes cities such vital--such magical--places.

When not wandering our streets, Christopher DeWolf is the editor of Urbanphoto.net. The Urban Eye appears every second Friday.