The base was done in several steps
1) Apply elmer's white glue to the base
2) Glue several large fake rocks on the base
3) Sprinkle the base with some small gravel
4) Reapply some watered down Elmer's in choice places around the rocks and in the open spaces
5) Push down some small pieces of green moss-like lichen normally used for model railroading where the new glue was added
6) Apply some Scenics Cement with a dropper (also used for model railroading) on the whole base and on some of the rocks
7) Sprinkle greenish flock to the entire base.
8) Paint the rim around the base black
And that is "it"