Nursery plants are often overgrown and need much pruning to establish their best form. Through pruning, you control growth and form by removing excess foliage and ugly limbs.
Some points to remember when pruning are:
- Make all cuts above a bud, a side branch or a main fork of the tree. Remove all buds except those on the outside of the trunk to force the growth outward and upward.
- Leave stubs flush with the stem; long stubs serve as an entry for insects.
- Avoid cutting back so far that you weaken the main branches.
When pruning, keep branches growing toward an open space instead of toward each other or the trunk. Do not shear bonsai as you would cut a hedge; shearing makes the plant look artificial.
After deciding on the foliage form for your bonsai, remove all crossed branches until the tree takes on the form you selected.
If you want to slant a tree that has been growing in an upright position and insure that branches take a natural shape, prune it in an upright attitude, and then tip it to where it should be and work on it that way.
Next, cut back new growth and thin out excess branches. When pruning an upright style, remove unneeded side branches and leave the center ones that will fill out as they grow.
Space out your pruning schedule, even if the plant has heavy foliage. Plants must have a certain number of leaves for photosynthesis.
Protect pruning scars when removing heavy wood from thick branches or the trunk. Cut the wood as close to the trunk as possible, pare the stump flush, then scoop it out with a chisel, making a shallow wound that will heal without looking unsightly. Treat these wounds with grafting compound and they will be unnoticeable after healing. Several years must pass before the bark will grow over these cut surfaces and replace the scar tissue.