Lush Sanctuaries of Survival:

How Sri Lanka's Home Gardens Are Healing a Biodiversity Crisis

- BY IFHAM NIZAM

At a time when deforestation, monocultures, and climate chaos are rapidly eroding the natural wealth of Sri Lanka, a quiet revolution in conservation is flourishing right outside people's front doors.

Sri Lanka's traditional home gardens are now being recognised not merely as spaces of subsistence but as dynamic arks of biodiversity. A groundbreaking 15-year study led by biodiversity scientists Suranjan Karunaratne, Dushantha Kandambi, and Thilina Surasinghe has revealed that a single 36-perch garden in Rambukpitiya, in the central highlands of Kandy District, has evolved into a thriving microrefugium for more than 250 species-95 of them endemic and 74 threatened, including seven classified as Critically Endangered.

"Home gardens can no longer be dismissed as marginal green patches. Our findings show that, with thoughtful management, they can act as lifelines for species teetering on the edge," Karunaratne told The Island.

The transformation began in 2008. The land, initially dominated by banana (Musa acuminata) cultivation, was gradually rewilded. Banana trees were phased out, native tree species such as Artocarpus heterophyllus (jackfruit), Magnolia champaca (sapu), Swietenia macrophylla (mahogany), and Persea americana (avocado) were introduced, and leaf litter-once removed for aesthetic reasons was allowed to accumulate naturally.

This shift created a complex multilayered habitat mimicking forest conditions, providing shade, moisture, and rich detritus layers that sustain a wide array of organisms. Amphibian and reptile populations surged, butterflies and dragonflies nearly doubled, and new microhabitats formed, supporting even ground-dwelling earth snakes and freshwater crabs.

"Biodiversity doesn't always need a forest. It needs space, complexity, and protection. And we proved that even a home garden could offer that," Kandambi says.