Albizia saman is native to the lowland dry forests and savannas of tropical Americas, thriving at elevations ranging from sea level up to 1,300 meters and preferring full sun exposure. This tree requires minimal maintenance and can adapt to various soil types. Given its expansive canopy, it is advisable to plant Albizia saman at distances of up to 18 meters alongside roads and 24 meters in open areas. Propagation can easily be achieved through stump, stem cuttings, or seeds. For quicker germination, seeds should be soaked in hot water for 3 minutes followed by 24 hours in cold water.

The rain tree is well-known for its robust response to pruning and coppicing, quickly regenerating when trimmed or pollarded. Even after being entirely felled and the remaining trunk decaying, new rain tree sprouts often emerge from the roots. Additionally, the Albizia saman tree is known for its abundant seeding, with reports suggesting that a 15-year-old tree can produce up to 275 kilograms of pods annually. This high seed production presents a challenge when the tree is introduced outside its native habitat, particularly in urban areas. While considered moderately invasive, the Australian government has labeled Albizia saman as undesirable in environmentally sensitive regions. Furthermore, in regions with high rainfall such as Malaysia and Indonesia, the tree tends to be shallow-rooted, causing damage to infrastructure like roads, sidewalks, and lawns, unlike when grown in drier areas with deeper roots.

Albizia saman was historically dispersed by now-extinct Pleistocene mammals, but today its seeds are now primarily spread through consumption and dispersal by cattle and other vertebrates, as well as through the natural breakdown of the pods on the ground.

Trees that have been grown from seed germination display a stronger resistance to plant diseases and may even hinder their spread. Seed germination is also an effective method to achieve diverse plant shapes, as evidenced by local nurseries in Singapore where seeds from different mother trees have resulted in a majority of seedlings with a normal green form (80% - 100%), a smaller percentage with a yellow form (0% – 20%) or green small leaf form (0% - 10%), and a few with a unique clingy variant (0% - 5%). This phenomenon further highlights the varying phenotypes seen in trees across their natural habitats.

In Malaysia, the Kerenga ant is a common insect that is often seen on trees, particularly those with resin-rich bark. These ants are well-known for their aggressive colonization and can be intimidating to visitors and pedestrians alike. Another insect commonly found on trees is the Cicada, which feeds on the nectar that is secreted from the leaf petiole. Cicadas produce drizzile honeydew-like substance, which is one of the reasons how the Albizia saman tree is also known as the Rain Tree.

Albizia saman (Fabaceae)