88mkiii,
no, it is in soil. However years ago search was done for a local moss, that could handle growing in full sun and Bonsai type watering. Long story and a good laugh, the moss was found growing in the backyard on the asphalt covering.
It is present in all the pots, and as the rains fall, it grows well covering the surface of the soil. Nice protection from the at times heaby rain.
No need to plant it either, now it just shows up.
Hope that is what you wanted to know.
Good Morning
Anthony