Grey box Eucalyptus microcarpa, red gum E. camaldulensis and blue gum E. leucoxylon occur naturally in this area and some trees pre-dating white settlement remain. Shrubs which are native to the site include golden wattle Acacia pycnantha, sweet bursaria Bursaria spinosa, Dodonea viscosa, Pittosporum phillyraeoides and native lilac Hardenbergia violacea.
Previously sheep were used to keep the grass low. With the removal of grazing in 1991, the native understorey has regenerated. There are now fine stands of wallaby grass Danthonia spp. and spear grass Austrostipa spp. in the Arboretum as well as many other small native plants such as climbing saltbush Einadia nutans and windmill grass Chloris truncata. Eight native species of conservation significance have been identified. The Arboretum contains some valuable remnants of the original Adelaide Plains flora.
A dedicated group of volunteers are helping to conserve and restore the original flora by the control of weeds and propagation of locally collected seed for replanting.