Reverse Graffiti Project

(image by Christine van Doesburgh)
If you see the outlines of flowers on the sidewalks in Amsterdam, it wasn't because of that puff you took at the coffee shop; artist Christine van Doesburgh has been spiffing up the neighborhood with "reverse graffiti"

Inspired by the Reverse Graffiti project (photo above), van Doesburgh made stencils of local plants and used a high-pressure water hose (usually used to clean graffiti off of walls) to stencil the plants onto the ground.

Here are a few more photos of the Amsterdam ones: