Havana, CUBA — Karen Washington and Justo Torres have a lot in common. Both turned plots in their dense urban environs into gardens. Both are fresh food advocates, selling their produce in local markets and teaching gardening workshops.

They both love the land — it’s just a matter of where. While Washington weeds in the Bronx, Torres cultivates in Cuba.

Despite the divide, the two got to swap composting secrets and tilling tips in person during an American delegation to Cuba in 2004. For Washington, the encounter sowed the seeds of what is possible in local farming.

“These are people who were left with nothing, and were able to survive on their own self-sufficiency,” said Washington, 51. “It was absolutely incredible.”

The trip was organized by Just Food, a New York City nonprofit that advocates for local food production and farming, to learn about Cuba’s agricultural renaissance. “Havana is the city that urban agriculture experts talk about as a great example,” said Kathleen McTigre, a Just Food staffer. “Everyone knows how to grow stuff there.”

That wasn’t the case when Cuba, like the U.S. today, had easy access to fertilizer and fuels. When the U.S.S.R. collapsed in 1989, Cuba abruptly lost its main trading partner. As a result, its mechanized agricultural system was decimated. Tractors rusted and crops spoiled in the fields, leaving food supplies short and bellies hungry.

As the crisis worsened, Cuba’s government initiated an agricultural upheaval in 1993. Organic pesticides were developed and farming went small scale. Parcels of land in big cities like Havana were turned into cooperative farms, thereby shortening shipping distances, and local markets were opened to sell what was produced. Neighborhood gardens, whether on an office building’s lawn or in someone’s backyard, were also encouraged.

The results have been dramatic. Urban farms now produce 60 percent of the island’s vegetables, according to a report by Oxfam, an international development agency. Total yields have doubled or tripled each year since 1994, and thousands of Cubans now cultivate their own local plots.

Torres is one of them. In 1997, he cleaned out the garbage behind his Havana home, scoured the trash for planting containers, and rigged a watering system. He arranged a compost bin and planters — ranging from old tires to porcelain tubs — throughout his backyard and on the building’s roof.

The concrete plot is now a lush jungle of vegetables, fruit and herbs, along with some livestock. What he doesn’t use, Torres sells in a monthly market. He now teaches workshops in community gardening and encourages his neighbors to pass up porkchops for bok choi.

“It’s all about good health and eating better,” said Torres during an interview at his home in December. “I wouldn’t be able to have these things in my diet otherwise.”

Alberto Rojas took over a large plot two years ago for the food and the sheer joy of farming. The garden, fenced in behind a garbage-strewn street, now brims with cabbage heads and fig trees. “It’s an affair of my heart,” said Rojas, 72.

Washington shares that passion, and was thrilled to see it on such a grand scale. “We were exchanging the same stories,” she said.

Back in 1987, Washington helped transform a junky Crotona lot into a community garden through the Bronx Green-Up program, an urban agricultural initiative run by the New York Botanical Garden. The Garden of Happiness has continued to thrive and now offers classes and provides produce for a Tremont Avenue farmers market.

“Here in America we are so used to having things come out of a box or out of can,” Washington said. “We are educating people that, yes, apples and tomatoes are grown right here.”

Washington and McTigre give lectures on Cuba’s agricultural successes to community farmer groups and, last year, at the Botanical Garden. Ena Nemley, a North Fordham gardener, found it inspiring.

“I would love to go there and see hands-on how they live and do this,” said Nemley, 75, who has worked in the Bainbridge Avenue Lotbusters garden for 20 years.

McTigre hopes to organize more exchanges between the two countries, but travel restrictions to Cuba make it unlikely. “Any gardener would be risking something,” she said, referring to possible fines. Many educational delegations to Cuba were banned after a further tightening of the U.S. blockade in 2004.

The restrictions are frustrating for both sides. “[People from] the U.S. miss out in learning about this,” said Francisco Paz, a member of the Community Patio Project, a Cuban gardening group. “There are many things in common in all cities, even New York.”

Washington knows that first-hand. “The commonality is there,” she said. “The language was different, but we both spoke [about] a love for the earth and the richness that it produces.”