What has your experience been like with this variety? Ryusen recently became widely available in eastern canada, and they have tiny leaves!
They are a zone 6 tree for us now from several in a zone 5 losing their material when we had two arctic temps back to back winters. Other than that...I have never had an issue with any fungal issues or even pests from this tree.
The tree above I shared...here it is from spring 2015. If you wish to put it in the ground and are below a zone 6...Pass. If you can protect in a pot. I have mine in a cold greenhouse. Used to be set to 27F. Now, is at 30F because of satsuki azaleas. But...tree is a dream, if you like weeping, it's not one your fighting to keep it so. In a pot a tree looses a zone cold hardiness.