bonsaiTALK Community - View Single Post - California Juniper rehab

Carl, the image shows how this may develop over time. A lot of cutting back was just done, and it will take some time to tighten up the foliage.

Bob, bonsai that are negelected for long periods usually have a number of problems in common. Lack of nourishment, not enough water, being rootbound, etc.
I start by removing the rootball from the pot. Sometimes it's necessary to break the pot. I'll then put the rootball in a tub of water with some soluable fertilizer for a long soak, sometimes overnight. This accomplishes 2 things. Rehydrating the tree, and sending some nourishment through the system.
After this is done, I'll use a hose to wash some of the old soil away from the roots, top, sides and bottom. Then into a training pot with a good gritty bonsai mix. Sometimes I'll pack spagnum over the top of the roots to encourage surface rootage. When these roots develop, and it's time to repot, I'll be able to remove roots from the sides and bottom of the root ball.
I think it's necessary to keep a feeding program going, using some kind of slow and constant release fertilizer. Gro-Power 12-8-8 slow release tablets are my favorite.
This process might take a couple of years depending on the tree's condition. Usually theres some positive response in a fairly short time with the foliage greening up and new growth starting to pop. We're talking mainly about coniferous trees here, especially junipers, but I know of no reason that some version of this process wouldn't work for most trees.
I hope this answers your question.

Mike
Edit: Bob, you asked about sunlight. Good question. In my coastal climate I try to give junipers and pines full sun. In the case of the rehab project, I start it out in at least half-day full sun , if not more.
I left out 2 important parts of the process, foliage misting and feeding. The foliage should be misted a couple of times a day. Foliar feeding is very beneficial in cases like this, especially for junipers, because it takes some time for new feeder roots to form. I would say once a week with 1/4-1/2 strength water soluable fertilizer such as Miracle-Gro.