All things roughly equal, I decided to test the condition of the roots of these two Chinese Quinces; both 3-year-old cuttings, dug in March ’15, and severely headed back; both above and below. They’re both in roughly the same volume of soil, but here’s the difference:
White pot has soil that is bark, lava, turface, 1:1:2
Blue pot has soil that is lava and akadama, 1:2
Here is the one planted in akadama.
I’m also biased toward double-trunk trees, and I got used to seeing these two next to each other for the last year, so I thought I’d make it official: