I purchased a very nice shohin sized Sekka Hinoki this spring. The nursery was a few months late getting it to be me and it was getting hot. I up potted it into a pond pot without touching the roots due to high temps. I have no concerns about the trees health. It is growing very well with good color. I’m just curious that it doesn’t seem to have any root growth beyond the original root ball. Seems strange to me. Maybe I’ll find out more next spring but right now no evidence of further root growth. Any thoughts?
A lot of trees push most of their roots in the spring and the fall with little root growth during the summer. They put most of their energy into foliage in the summer.
If the soils are very different between the old and new soil the root may be having trouble crossing the boundary due to different water/oxygen conditions. When I do a slip potting like you did, I always loosen up the surfaces of the rootball and work some of the new soil into those areas to avoid an abrupt transition.
I usually will disturb the roots a bit myself. I don’t have any experience with Sekka Hinoki so I erred a bit to the safe side with the heat issue. Thanks for your thoughts. I think I’ll stir them up a bit when the weather turns and winter it over with the pot in the ground to protect the roots.