Recently i learnt about the wonderful idea of moss graffiti. All you need to do is make a moss ‘paint’ that you can paint onto surfaces to make miss grow. It’s a big new graffiti trend as it is allows the artist to leave their mark whilst also being green and considerate of other people’s views on art in public spaces.
It’s really easy to do, all you need is moss collected from walls and a few easily acsesiable materials which you all blend blend together to make a paint like texture, which you can apply to walls. I will have to give it a go sometime!