bonsaikc

Wayne,
Vance has shown that mughos should be repotted in summer. Why? Because if you do it in spring they suffer and may die. Japanese black pines, however, respond well to early spring repotting. This leads me to believe that they may not do as well when repotted this time of year. I have always done my root work on JBP in early spring before the candles elongate.

Of course, yesterday I had to dig up a dozen or so JBP seedlings that went in the ground this spring. I didn't know then that I would be moving this week (into a motel, no less). Fortunately this was the week the heat broke. Hopefully it will be merciful to them, but if I lose them all, so be it. It can't be helped.

How long? That depends entirely on your knowledge of bonsai in general and JBP in particular. But as a guideline, I would say that you should ignore any short-needle techniques for a few years. Repot next spring and do some good root work. When the tree recovers, feed very heavily and let it grow. Let the candles grow to six feet long if they want to. Then cut back fairly hard next fall, especially removing undesireable forks, reducing top growth, etc. You will get some back budding on wood that is not over about ten years old. Ony do this, though, if the tree has recovered and put on very good growth.

Plan your trunk chop carefully. Leave as much as a six inch stub when you do that, and let it dry out for a year. You will eventually carve this, but it will help eliminate excessive bleeding. I'm not certain that I would trunk chop the year after repotting unless the tree was exceptionally vigorous. I'd also let the proposed leader take on some good strength first.

Ten years? Five if the tree was exceptional stock and you were Boon? Hard to say really, but consider it a long-term project. Post photos when you get a chance.

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