I only apply green moss- not to be confused with the milled sphagnum moss I liberally apply to the soil surface of many newly re-potted trees- to trees that are being shown. I'll decide after the show whether the moss stays or goes, and if the tree is going into winter storage for a few months, the moss might go with it. Fwiw, the vast, vast majority of my trees don't have moss on their surface right now.