I have a Japanese maple bonsai with a trunk diameter about 1" thick and a rootball 11" in diameter by 2" deep. It’s probably been growing for a while (5-10 years?). When I got it last fall the soil was in very poor condition. I’m repotting now before the buds start breaking.
I took it out of its pot and it’s pretty root bound, so I am cutting back the long roots to about where the soil starts. The question I have is, how much soil can I take off and how far to cut back the roots?