A tale of a single Pterostylis gibbosa plant   (a.k.a. Oligochaetochilus gibbosus)

by Ross Morrison and Jim Cootes

A number of dedicated lovers of Australian native orchids have made a decided difference for a rare and endangered terrestrial orchid species. It is a fine example of what can be done, by a few people, to help propagate rare orchid species. Even more importantly discussions are now underway for artificially grown plants of this orchid to be returned to its’ original habitat.

Pterostylis gibbosa is listed as endangered by both state and federal governments. This rare species is only found in the Illawarra area of New South Wales and is only known from a few locations.

The tale of this single plant is very interesting and one of patience, dedication, and commitment.

In 2000, John Riley (first Life Member of Macarthur ANOS) collected this plant under the Australian National Botanic Garden Licence for Mark Clements from an area in South Nowra, New South Wales. The collection was to allow John Riley to draw the species in flower.  These drawings were then used in the publication: Orchids of  Australia by John Riley and David P Banks. This beautifully illustrated book was first published in 2002 by the University of New South Wales Press.

In 2005 John Riley moved from his Leumeah home to reside on the Mid North Coast (Moorland) of New South Wales. John gave the single plant of Pterostylis gibbosa to his long-time friend Terry Cooke  (second Life Member of Macarthur ANOS). Terry was never able to flower the single plant again. In 2013, Terry gave the plant to his mate, Ross Morrison (Secretary, Macarthur ANOS), who was able to flower the plant in 2014 and subsequent years. This single plant has flowered each year since 2014 and has not been re-potted to ensure no tuber disturbance occurs.

In 2019, Mike Harrison, self-pollinated the single flower of this plant. The resultant seed capsule was consequently sent to Richard Thomson OAM and the seed propagation team in Victoria. This team includes Bryan Lawrence, Helen Richards, Neil Anderton, Andrew Gibbons, and Wendy Bedggood.

In December 2021, Richard sent Ross Morrison a total of 50 tubers of Pterostylis gibbosa. All the tubers were planted in January 2022 and in September 2022, all of the tubers generated rosettes and most flowered.  These plants have again been pollinated and we anticipate more plants in the future.