HAVANA - For Miladis Bouza, the global food crisis arrived two decades ago. Now, her efforts to climb out of it could serve as a model for people around the world struggling to feed their families.

Bouza was a research biologist, living a solidly middle-class existence, when the collapse of the Soviet Union - and the halt of its subsidized food shipments to Cuba - effectively cut her government salary to $3 a month. Suddenly, a trip to the grocery store was out of reach.

So she quit her job and, under a program championed by then-Defense Minister Raul Castro, asked the government for the right to farm an overgrown, half-acre lot near her Havana home. Now, her husband tends rows of tomatoes, sweet potatoes and spinach, while Bouza, 48, sells the produce at a street-side stall.

Neighbors are happy with cheap, fresh vegetables. Bouza never lacks fresh produce, and she pulls in between $100 and $250 a month, many times the average government salary of $19.

"All that money is mine," she said.

Cuba's urban farming program has been a stunning, and surprising, success. The farms, many of them on tiny plots like Bouza's, now supply much of Cuba's vegetables. They also provide 350,000 jobs nationwide with relatively high pay, and have transformed eating habits in a nation accustomed to a less-than-ideal diet of rice and beans and canned goods from Eastern Europe.

"It's a really interesting model looking at what's possible in a nation that's 80 percent urban," said Catherine Murphy, a California sociologist who spent a decade studying farms in Havana. "It shows that cities can produce huge amounts of their own food, and you get all kinds of social and ecological benefits."

Of course, urban farms might not be such a success in a healthy, competitive economy.

As it is, productivity is low at Cuba's large, state-run farms, where workers lack incentives. Government-supplied rations provide such staples as rice, beans and cooking oil, but not fresh produce. Importers bring in only what central planners want, so the market does not correct for gaps. And since most land is owned by the state, developers are not competing for the vacant lots that can become plots for vegetables.

Still, experts say the basic idea behind urban farming has a lot of promise.

"It's land that otherwise would be sitting idle. It requires little or no transportation to get [produce] to market," said Bill Messina, an agricultural economist at the University of Florida in Gainesville. "It's good anyway you look at it."

And with fuel prices and food shortages causing unrest and hunger across the world, many say the Cuban model should spread.

Other countries have experimented with urban farming - Cuba's initial steps were modeled after a green belt surrounding Shanghai. But nowhere has urban farming been used so widely to transform the way a country feeds itself.

"As the global food crisis receives attention, this is something that we need to be looking at," Murphy said. "Havana is an unlikely, really successful model where no one would expect one to come from."

One of the first plots Raul Castro opened as an experiment in the early 1990s was in a ritzy Havana neighborhood. The half-block farm - owned by a government agency - is surrounded by apartment buildings and houses, but also offices of foreign companies, a Spanish bank and the South African Embassy.

Long troughs brim with arugula, spinach, radishes and basil, and few of the 20,000 square feet are wasted.

One technician tends compost, while another handles natural protection from pests. Three workers tend the crops, and three sell them from a brightly painted stall.

Key to the operation is something once unheard of in Cuba: 80 percent of the profits go straight to the workers' pockets, providing them an average of $71 a month.

"Those salaries are higher than doctors', than lawyers,' " said Roberto Perez, the 58-year-old agronomist who runs the farm. "The more they produce, the more they make. That's fundamental to get high productivity."