Step 9: Step Nine: the First Layer of Your Terrarium CLAY
Now that your bottle is clean, you can add your layers of stuff to grow your tiny plants in.
HERE ARE THE LAYERS
BOTTOM TO TOP
So your first layer will be the clay make tiny balls of it and put them into the bottom of the bottle and tamp them down with your tamper until you cover the whole bottom of the bottle. This will hold your tiny rocks into place.