Guidelines for establishing a verge garden in Brisbane are at https://www.brisbane.qld.gov.au/clean-and-green/natural-environment-and-water/plants-trees-and-gardens/verge-gardens

“Residents are encouraged to use native or water-wise plants where possible.”

You cannot include trees on your verge garden but if you don’t already have one, you can apply to the Council for a free street tree.  They will decide on the type of tree and position, and you can plant around it.