So how much soil is available? Just a guesstimate.......depth, size of area, etc. And does it have free drainage? Open soil underneath?

A very constricted root run can limit or stunt growth, just as it would in a container. But in a container, it is far easier to lift the plant and do the necessary root pruning to accommodate the limited space than it would be with one planted in the ground.

And Red Dragon gets much wider than you would expect so also some concern that its growth would be adversly impacted by such close proximity to the wall.

It's sandy loam on top of a hill. Drainage is great. The place against the wall is all soil. It isn't concreted underneath. It is just boxed in at the surface.

It's about the same size as the pot its its in currently which is why I was concerned the flower bed to the right might work better.

The other option might be to grow it in a large container on top of the concrete ?

Off to the right might be better. Seems like more room to spread out horizontally. Or a container........enough room to balance one up there?

There is about 5 ft between the wall and the pond.