Good Morning Debbie!
The column is built around a 4" PVC pipe. In the bottom of the planter portion are about 8 holes that drain into the PVC pipe. The pipe is open on the bottom so it drains onto the ground. The dark flecks are bigger pieces of peat moss in the hypertufa. Some of the dark spots are actually small holes where the peat moss has worn out of the tufa. I like the aged effect that give it.
