To begin the recipe, first of all
gather together several clumps of moss (moss can usually be found in
moist, shady places) and crumble them into a blender. Then add the beer
and sugar and blend just long enough to create a smooth, creamy consistency.
Now pour the mixture into a plastic container.
Find a suitable damp and shady wall on to which you can apply your moss
milkshake. Paint your chosen design onto the wall (either free-hand
or using a stencil). If possible try to return to the area over the
following weeks to ensure that the mixture is kept moist. Soon the bits
of blended moss should begin to re-couperate into a whole rooted plant
– maintaining your chosen design before eventually colonising
the whole area.
clipped from: www.storiesfromspace.co.uk 
