The policy for Nature Strips is at the bottom of the page about Community Gardens.

This is the first policy I have seen state explicity something that is core to the issue of planting on public land:

They are to be consistent with the appearance of the streetscape and they must not make the nature strip look like private land.

A PDF copy of their policy can be downloaded from the link at the bottom of
https://mosman.nsw.gov.au/environment/community-gardening