Durabaculum undulatum

golden orchid


Durabaculum undulatum

(R.Br.)M.A.Clem & D.L.Jones 2002

pronounced: due-rah-BAK-yew-lum un-dew-LAH-tum

(Orchidaceae — the orchid family)

synonym — Dendrobium discolor

Lindl. 1841

pronounced: den-DROH-bee-um diss-KULL-uh

common names: golden orchid, mangrove orchid

native 4Durabaculum undulatum is now the official name, at least in Australia, for the Golden Orchid, but most gardeners will still want to refer to it by the synonym. Durabaculum is from two Latin words, durus, hard, and baculum, a stick, staff; undulatum is also Latin, from undulatus, undulated, wavy. Dendrobium is from the Greek δενδρον (dendron), a tree, and βιος (bios), life – tree of life, while discolor is Latin for ‘of another colour, of varied colours’.

This is a real Aussie tough guy. It can grow up to 5 m, out in full sun, and can even cope with salt spray. It loves to sit on rocks basking in the sunshine, and if it can find a tree or other support, it can shoot upward for years. Its one requirement is strong light.

The Golden Orchid occurs naturally on coastal mangroves and rocky cliffs near the sea in eastern Australia from Gladstone north, the Torres Strait islands and New Guinea. It usually grows in extensive, interconnected colonies, joined by sprawling aerial growths. It flowers often and profusely. It used to be commonly found throughout its territory; but humans have impacted on those populations growing in the more accessible areas, and collectors have removed many.

The short ovate leaves grow alternately over the whole length of the stems. The axillary flower buds develop into short flower stalks with 1 or 2 terminal flowers. The orchids grow quickly throughout summer, but take a long rest during winter. In the spring, new shoots are formed from the base of the main plant and the dormant buds come back into action.

The beautiful sprays of flowers can be over a metre long, and the colours range from clear yellow to chocolate brown, and are the basis for many hybrid forms.

The fruits are capsules, porrect to pendulous, and dehiscent.

Solander collected the Golden Orchid during the voyage of the Endeavour. He named the plant Epidendrum exaltatum – the genus Dendrobium was not identified until some years after Solander’s death. Its placement into Durabaculum is quite recent, in 2002, and is not yet universally accepted by botanists. In the last decade a number of genera of Australian orchids have been subject to detailed research, which has included molecular studies which for the first time provide important information on the ancestral relationships of genera. As a result of these studies, Australian Orchidaceae has undergone significant taxonomic and nomenclatural changes at both generic and specific rank.


Photographs taken in Picnic Bay 2010, 2013, 2015
Page last updated 17th December 2018