The Annex was established to provide a frost-free environment for those species which could not be successfully grown in the cold winter climate of Canberra. The Annexe comprises about 15 developed hectares on an 80 hectare site. The site features paths through areas of both cultivated and naturally occurring plants. The Garden is open from 8.00am to 4.00pm Monday to Friday and from 10.00am to 5.00pm on weekends and public holidays. The Garden is closed on Saturdays from May to August and on Christmas Day and Good Friday.
Picnic facilities are available.
The tree fern species in the garden is Dicksonia antarctica . Fossil records show that it is one of Australia's most ancient plants. The pebbled path through the Fem Garden was laid by the artist and two assistants, using a dry mortar technique. The quartz and silica river pebbles come from an area near Coilector in New South Wales. It may be viewed from the foyer of the exhibition galleries, and from the observatory plafform at the end of the galleries of Australian Art.