The Australian Antarctic Foundation Subantarctic Plant House

Inside the Subantarctic Plant House at the Royal Tasmanian Botanical Gardens
Inside the Subantarctic Plant House (Photo: Royal Tasmanian Botanical Gardens)
Some of the flora inside the Subantarctic Plant House at the Royal Tasmanian Botanical Gardens

In the great Southern Ocean, approximately 1500 km southeast of Tasmania, lies a small island few people will ever have the opportunity to visit. Known as Macquarie Island, this relatively young landmass emerged approximately 600,000 years ago as a piece of deep ocean crust thrust above sea level by massive continental plate activity.

The Australian Antarctic Foundation Subantarctic Plant House was opened on October the 13th, 2000 by Sir Ninian Stephens in his capacity as the former chairman of the Australian Antarctic Foundation. The Subantarctic Plant House at the Royal Tasmanian Botanical Gardens displays the unique flora of Macquarie Island against a panoramic mural of the area. Painted by renowned Tasmanian artists, John Lendis, the mural reflects the rugged terrain and bleak beauty of the island and its vegetation.

The project is a world first, being the first purpose-built display environment designed to grow the flora of a subantarctic island. Measuring 14 x 6 metres the house is designed in the shape of a tear drop, with high curving walls and a clear polycarbonate roof. Internally it is cooled by piped cold water, air conditioning and a misting unit.

Visitors will not only have the opportunity to learn about the unique flora of the island but will gain a better understanding of what it actually feels like to be there, as the cold, wet and windy conditions have been recreated in the Subantarctic Plant House with the aid of a fogging system and fan-driven chiller unit.

Display plants include Poa foliosa, a grass tussock which can reach two metres in height and is the dominant plant on the island, and the two mega-herbs: the famous Macquarie Island cabbage, Stilbocarpa polaris, which was used against scurvy by whalers of yesteryear and a large silver grey leafed member of the daisy family, Pleurophyllum hookeri.

Other species may look familiar including cushion plants Azorella macquariensis and Colobanthus sp., grasses Festuca contracta and Agrostis sp., and the fern Polystichum vestitum. The common buzzy Acaena sp., whose seed heads stick to our socks, also grows on Macquarie Island. The buttercup family is represented in the form of Ranunculus crassipes. The Heard Island plant, Pringlea antiscorbutica will also be on display.

The house has been largely funded through the generosity of the Australian Antarctic Foundation as the major sponsor with significant contributions from a number of other Tasmanian businesses. The development of the house has been greatly facilitated by valuable assistance from scientists and staff from the University of Queensland, the Australian Antarctic Division and Tasmanian Parks and Wildlife.

As the newest plant display at the Botanical Gardens, the Subantarctic Plant House provides a fascinating glimpse of plant life on Macquarie Island and for most people it will be their only opportunity to experience first-hand the subantarctic flora of 'under, down under'.

Mark Fountain
Royal Tasmanian Botanical Gardens