May I offer a suggestion, Darlene, to take this tree - which has really great potential - to the next level?
1. Take it out of its pot, but leave it draped over the rock.
2. Make a number of small nicks through bark to the sap wood of the exposed roots, from way up pretty high (even, perhaps, to the very base of the trunk where the roots start), down to about mid way to where the soil had been when it had been in the pot.
3. Put root stimulator lavishly along the ares you have nicked.
4. Put some moist/wet soil thinly around the roots, wrapped in plastic wrap.
5. Hang it down as a cascade on the edge of a really huge, deep pot, (since it will be hard to put a cascade in the ground).
6. Starting in the Spring, feed the crap out of it for the next 5+ years.
7. When you dig it up, the way the roots will look draped over the rock should be stunning, and it will be a spectacular cascade in the right pot.
Hope that helps.