Ficus elastica

''Ficus elastica'', the rubber fig, rubber bush, rubber tree, rubber plant, or Indian rubber bush, Indian rubber tree, or rambung is a species of flowering plant in the family Moraceae, native to eastern parts of South and Southeast Asia. It has become naturalized in Sri Lanka, the West Indies, and the US state of Florida. Its common names reflect its historical use as a source of rubber within its native range, but it is not used in the modern commercial-scale production of natural rubber.

Description

It is a large tree in the banyan group of figs, growing to – rarely up to – tall, with a stout trunk up to in diameter. The trunk develops aerial and buttressing roots to anchor it in the soil and help support heavy branches.

It has broad shiny oval leaves long and broad; leaf size is largest on young plants (occasionally to long), much smaller on old trees (typically long). The leaves develop inside a sheath at the apical meristem, which grows larger as the new leaf develops. When it is mature, it unfurls and the sheath drops off the plant. Inside the new leaf, another immature leaf is waiting to develop. The canopy of the tree is dense.

Pollination and fruiting

As with other members of the genus ''Ficus'', the flowers require a particular species of fig wasp to pollinate it in a co-evolved relationship. Because of this relationship, the rubber plant does not produce highly colourful or fragrant flowers to attract other pollinators. The fruit is a small yellow-green oval fig long, barely edible; these are fake fruits that contain fertile seeds only in areas where the pollinating insect is present.

Range

The natural range of ''F. elastica'' extends from Nepal in the north to Indonesia, Bhutan, Northeastern India, Bangladesh, Myanmar, Thailand, Yunnan in China, and Malaysia. It has been widely introduced in most tropical regions of the world, including Hawaii and the West Indies. In Europe, it can be found in mild locations throughout the Mediterranean Basin.

Cultivation and uses

In parts of India, people guide the roots of the tree over chasms to eventually form living bridges. To this day there are large bridges woven from aerial roots in Meghalaya, India. Although the trees used for these bridges are very large, aerial roots can be found on ''F. elastica'' as small as 1 feet tall.

Latex

All parts of the plant contain an abundant milky white latex, a chemical compound separate from its sap and carried and stored in different cells. The latex of ''Ficus elastica'' can irritate the eyes and skin, and is toxic if taken internally. Its sap can be used to make rubber; it was once the most common plant in Sumatra and Malay Peninsula for tapping before the Pará tree (''Hevea brasiliensis'') was introduced from Brazil in the late 1800s and became popular since then. Rambung trees were very valuable to farmers in Aceh who could find them in their newly cleared lands. The latex of ''Ficus elastica'' has been tested for use in the manufacture of modern rubber, but without economic and technical results.

Ornamental

''Ficus elastica'' is grown around the world as an ornamental plant, outside in frost-free climates (though it also tolerates light frosts) from the tropical to the Mediterranean and inside in colder climates as a houseplant. It thrives in USDA hardiness zones 10–12.Ficus elastica (Rubber Tree)
by Gardenia.net. Retrieved 1 May 2025. Although it is grown in Hawaii, the species of fig wasp required to allow it to spread naturally is not present there.

In cultivation, it prefers bright sunlight but not hot temperatures. It has a high tolerance for drought, but prefers humidity and thrives in wet, tropical conditions. Ornamental hybrids (such as Robusta) have been derived from ''Ficus elastica'' with broader, stiffer and more upright leaves than the wild form. Many such hybrids exist, often with variegated leaves.

Most cultivated plants are produced by vegetative propagation. This can be done by cuttings or by layering.

Gallery

File:Ficus elastica - Köhler–s Medizinal-Pflanzen-206.jpg, Illustration from ''Köhler's Medicinal Plants'' (1887)
File:Living bridge formed of the aërial roots (33071614871).jpg, An 1854 illustration of ''Ficus elastica'' trained as a living bridge
File:Ficus elastica Ficus lutea.JPG, ''Ficus elastica'' leaf on the left compared to '' Ficus lutea'' on the right
File:Ficus elastica figs.jpg, The figs of ''F. elastica''
File:Ficus elastica.jpg, ''Ficus elastica'' near the roadside in Savusavu, Fiji, showing the effects of constant pruning on the growth form.
File:Ficus elastica.Ghana.jpg, A huge ''Ficus elastica'' tree in Ghana showing the aerial roots.
File:Rubber Plant (Ficus elastica 'Robusta').jpg, Many cultivars, such as this ''Ficus elastica'' 'Robusta', are common in the houseplant trade
File:Starr 080117-1722 Ficus elastica.jpg, A variegated cultivar
File:Ficus elastica (rubber plant).jpg, ''Ficus elastica'', commonly called the rubber plant.
File:Ficus10.jpg, Ficus black
Ficus elastica tricolor-1-R.M. Nagar-bangalore-India.jpg, ''Ficus elastica'' 'Decora' ('Ruby' in Australia), a cultivar with pinkish hues

References

{{Taxonbar, from=Q160576

elastica
Epiphytes
House plants
Ornamental trees
Flora of tropical Asia
Plants described in 1819