Ok I've been developing the stop motion set for string in my back shed. The set is about 12 ft by 8ft. I've been digging up dirt and bringing it in along with branches and moss. Lots of big rocks and small flowers that dry up nice. The dirt tends to be dry and rocky so you have to break up alot of the dirt with your hands. The dirt also contains alot of clay, so when I soak it down with water it sticks together nicely. finally taking the finer dirt to make a top layer than bits of moss, store bought and found for the top layer. This will eventually look like a forest!