Get a larger container :-) Or a smaller plant to begin with.

there is a container forum ... perhaps you need to discuss from the the perspective of the pot ...

ken

Thank you. I am new to this forum and wasn't sure where to post. Sorry to bother :)

Posting here is fine. And my comments would not change to a posting on the Container Gardening forum - get a larger pot or start with a smaller plant.

As a maintenance procedure where containers are already as big as can be managed you can shear the roots once per year in spring, replace the soil around the sheared zone. Routine re-potting and root pruning are done to help maintain bonsai for instance. Of course as with the pruning of the roots of bonsai some associated dwarfing of the tops of box given this same treatment should be expected also.