The Australian Mediterranean region, with 700,000 square kilometers, is the second-largest in surface area (this region represents just over 20% of the biome overall). It is formed by two separate sectors, located in the south and southwest of the continent. Some 8,000 species are known, of which 75% are endemic. The climate is Mediterranean with a certain tropical influence due to the proximity of the Oceanic monsoons; this influence means that the summer drought is not as severe as it is in our own region here. Even so, there is a high frequency of forest fires and soils are very poor in nutrients.
Besides the characteristic Mediterranean flora, plants from amongst the temperate flora in the southwest of the continent (the states of Victoria and New South Wales) also grow in the Australian area of the Garden, in addition to its characteristic Mediterranean flora, plants are also cultivated selected from the temperate flora of the southeast of the continent (states of Victoria and New South Wales). Trees and bushes alike are dominated by a large number of species from just a few families, such as Mimosae (Acacia), Myrtaceae (Eucalyptus, Melaleuca, Callistemon) and Proteaceae (Hakea, Banksia, Grevillea).
Also present are other remarkably singular and primitive species of trees, which are characterised by displaying homogeneous behaviour during their growth:
- Xanthorrhoea or grass trees with very narrow, non-fleshy leaves, surprisingly well adapted to fires.
- Casuarinas and conifers from the cypresses group (Callitris genus).