View ‘Not just weeds’: how rebel botanists are using graffiti to name forgotten flora
In the Guardian, May 1, 2020.
A rising international force of rebel botanists armed with chalk has taken up street graffiti to highlight the names and importance of the diverse but downtrodden flora growing in the cracks of paths and walls in towns and cities across Europe.
Also view their Wild Cities page.
I guess this is a next step from Guerilla Gardening!