Moss/lichen on sealed or unsealed projects?
I have a concrete leaf on which I'd like to grow moss or lichen. I haven't sealed it yet and wonder if the culture will take hold on a sealed item. I'd like to leave it out all winter but don't know if doing so with it unsealed would be safe. It has been cured. Also, is there any benefit in throwing in some baking yeast to encourage moss growth? Thanks for your thoughts.