When Buck Harris and his partner, Mike, bought a 145-year-old Italianate house to restore adjacent to Cleveland's Ohio City neighborhood two decades ago, the neighborhood ambience included drug shootings and corner prostitutes.

"It was a war zone," Harris says. "The neighborhood was in dramatic decline at the time. It was known as where you go to get heroin."

Now, as Harris and other intrepid homeowners have gobbled up the vacant and foreclosed lots surrounding their houses over the years and worked to wipe out drug-related crime, the area has been transformed. Many of the nearly block-long lots, or "blots," they have created look as if they were lifted from a verdant suburb, with mature trees and a wide expanse of lawn.

Harris' neighborhood is just one example of how enterprising homeowners are changing the landscape in many depopulated cities, bringing the look of spacious suburbs to abandoned urban neighborhoods. 

For less than the cost of an airplane ticket, in some instances, owners can acquire lots next door to create their own oasis, complete with pools, courtyards or even orchards. Cities, meanwhile, are spared the upkeep of these properties.

"I think it's a good strategy" for our 60,000 vacant lots, says Marja Winters, deputy director of Detroit's Planning and Development Department. "In a lot of them, there's no interest, so why not put them in the hands of citizens that are going to own it and care for it?"

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This type of side-yard expansion, once expensive and time-consuming, has taken off in recent years as cities have foreclosed on abandoned properties, putting them in a land bank to be sold to interested parties. As the price and process have improved, the number of blots has swelled by the thousands in cities such as Detroit, Chicago, Cleveland and New Orleans, as well as other parts of the Rust Belt and Northeast.

In Detroit alone, the city approved 139 of these side-lot sales last fiscal year, and 123 in just the first part of this fiscal year. The New Orleans Redevelopment Authority has signed purchase agreements for more than 1,000 properties abandoned after Hurricane Katrina, according to published reports.

As the number of blots has grown, so have concerns about the effect they will have on future growth in these shrunken cities. Is it wise to create suburban spaces just outside of downtown? Or are these cities shortchanging future growth?

That depends, experts say, on how much demand there might be for some of these properties in the years ahead. "There are residential areas where there could be little to no demand for decades — places where I cannot foresee a future in 50 years," says Margaret Dewar, a professor of urban and regional planning at the University of Michigan who has studied blotting.