I would like to color the old ugly stone wall of my shed with lichen like oakmoss (Evernia prunastri) or common greeshield lichen (Flavoparmelia caperata). But how do I replant lichen? Which lichen are suitable?
PS: I mentioned those two lichen because I spotted them around in trees and other walls.
If the growing conditions on an old wall were suitable, the lichens would already be there. They need moisture to grow (though they can survive in a dormant state without it), and a stone wall that is exposed to wind and/or sun may simply be too dry. They are also sensitive to air pollution.
AFAIK you can't "replant" them in any practical way. You may be able to encourage them to colonize by painting the area with organic matter, e.g. a weak solution of yoghourt (ref: https://www.rhs.org.uk/advice/profile?PID=415)
Note that a typical patch of lichen only expands by 1 or 2 mm per year so whatever you try will not give quick results!
Forgive me as I can't completely recall if this is correct for Lichen or only for specific moss'. But I blended up a bunch of lichen, moss with a weak milk solution (3:1 with water) and sprayed it over a damp area in a garden. Fast forward a year and the entire area is covered in moss' and lichen. However, as another answer stated, the area needs to be hospitable to the lichen to begin with. So if that is not the case for the position you have in mind, you may be destined to fail.
