https://en.wikipedia.org/wiki/Guerrilla_gardening
Australia
Guerrilla gardening is prominent in Melbourne where most of the inner northern suburbs have community vegetable gardens; land adjoining rail lines has undergone regeneration of the native vegetation, including nature strips. There are a few minor disputes between guerrilla gardeners in Melbourne, with most falling into one of two groups: those concerned most with native planting and those concerned most with communal food growing. However, people with differing opinions still work together without dispute.[6]
There are small community groups around Australia called “Permablitz” who gather regularly to design and construct suburban vegetable gardens for free, in an effort to educate residents on how to grow their own food and better prepare them if/when food prices become too expensive.
Australian Network 10‘s show Guerrilla Gardeners featured a team of gardeners who make over areas of council owned property without them knowing.