The following article was written for the Orchid Species Bulletin published by the Orchid Species Society, which is based in Brisbane, Queensland in September 2009.

Bear in mind that any cultivation notes refer to the sub-tropical conditions of Southern Queensland, Australia.

Australorchis monophylla (F.Muell.) Brieger is one of my favourite scented orchids. Its strong sweet perfume has been described as being like lily-of-the-valley. Ferdinand von Mueller first described this species as Dendrobium monophyllum in Fragmenta Phytographiae Australiae in 1859. Von Mueller gave it the specific epithet from the Greek mono (one) and phyllum (leaf) for the unifoliate pseudobulbs.

Friedrich Brieger transferred Den. monophyllum to Australorchis in Orchideen in 1981. Based upon morphological and molecular studies, Mark Clements and David Jones (2002) have accepted this transfer. Members of Australorchis can be distinguished by the short several noded pseudobulbs with 1-2 long-lived apical leaves. In addition, multi-flowered racemes are produced from the upper nodes and the flowers have a 3-lobed lip.

A creeping mat-forming plant, Au. monophylla often forms small to large spreading clumps upon rocks or trees. Its ovoid conical, furrowed pseudobulbs are (2-) 6-10 (-12) cm long and 1.5-3 cm wide and are yellowish or somewhat orange to red-brown. The pseudobulbs are borne along a creeping, often branching rhizome at about 2 cm intervals. When young the new pseudobulbs are covered with thin brown sheathing bracts. With age, the pseudobulbs become longitudinally furrowed or ribbed.

At the narrowed apex of each pseudobulb is a single (rarely two) oblong, bright green, thin-textured leaf that is (5-) 8-12 cm long and 1.5-3 cm broad. Erect to arched racemes are produced from the apex of the pseudobulb and are 7-17 (-20) cm long, carrying 5-20 flowers. The bright yellow, cupped or bell-shaped waxy flowers of Au. monophylla often droop and are 6-8 mm across. Long-lived and lasting for over 4 weeks, the flowers produce a strong pleasant perfume.

Au. monophylla is one of our lovely Australian native orchids, which is distributed in the eastern tropics from the Fitzroy River in north Queensland to down as far as the Clarence River in New South Wales. It inhabits the branches of rainforest or sclerophyll forest trees and also grows on rocks or cliffs where it receives plenty of sunlight. In the northern range of its habitat it is rarely found below 600 m altitude whereas in the subtropical areas it is widespread from the coast to the mountains around 1,000 m elevation.

David Jones (1988) says that Au. monophylla can be difficult to grow unless it is given bright light, humidity and plenty of air movement. It prefers slabs of weathered hardwood or cork and can grow very well on suitable garden trees. In temperate areas it should be kept fairly dry over winter. Au. monophylla seems to like to dry out quickly between waterings. During the summer mounted plants should be watered frequently and I would suggest a winter minimum of 10 ^oC.