Wiring works because the actual practice of wiring causes the inner cambium to be stressed, and then fractured, which results in the tree adapting by making way for the stress, and growing in the direction that the owner wants.
In order for the wire to shape the tree, small stresses must be placed at various points along the length of the trunk or branch. This means the wire has to be stiffer than the trunk or branch. Otherwise, the wire bends rather than the tree.
Thicker wire is generally stiffer. Aluminum wire is easier to bend than copper, but lacks durability. Copper wire although stronger, can scar the bark if the wiring is not done right. Hence, aluminum is a suitable choice for beginners.
Practice wrapping on a tree branch of similar species to develop the dexterity needed. Test different thicknesses on test branches from a similar size and species before using any on the tree to be trained. Several different thicknesses will be required to do the entire tree – practice with all of them. Start with 1mm and work your way up to 4mm.
Practice, practice, and practice.
For starters, try your first wiring on your starter trainee bonsai trees (potentsai). It’s not sensible for a beginner to wire an expensive old bonsai; you may end up killing it!
Use a wire that is one third longer than the length of the branches or trunk you are wiring. Wrap from the base of the trunk upward, the lower, and thicker branches next, smallest branches last. When wrapping a branch, start at the base and wrap toward the tip. Wrap by holding the wire in one hand, and coiling the branch or trunk with the other hand, making sure not to move the wire that has already been coiled. Work from the base to the tip of the branch and end the wires with
You may want to apply some fabric as an intermediate layer between the wire and the bark in order to minimize the chances of scarring. Be very slow and careful as you go about it, and always listen for any sounds of cracking. If you hear any sounds like that, stop immediately and check for damage. Repair with tree paste or glue and do not work again with that branch for at least a year. Never wrap too tightly because the bark may grow and envelope around the wire after a while.
Try to avoid having the wires crossing unless it can’t be helped. There’s no physically necessary reason for this, other than some small additional stress on the branch at the point they cross. Crossing wires will result in greater pressure on the surface bark at the points where the wires cross.
Always keep an eye on your bonsai tree, during and after wiring is done. There is a high chance of the wires cutting into the bark and having the bark growing around it, especially at high tensile points. Actually, this will occur sooner or later, if you do not remove the wires beforehand. Several weeks is enough time to start rechecking and evaluating how much progress has occurred. If the tree appears to be growing fast, remove the wires, and rewrap again. Some fast growing species like Maple can present a challenge, in having to constantly wrap and rewrap.
The worst mistake is wrapping and forgetting all about removing the wires! If the wires cut into the branch later on, cut off the wire with special secateurs that are able to sever at the blade tips. It’s not a good idea to unwrap the wire, as you could break off some twigs or leaves in the process.
Wrapping bonsai trees should be done with utmost care. You are advised to obtain further reading, as this skill simply cannot be mastered overnight. But with dedication, even a total beginner can learn how to wrap properly and start creating beautiful literati or cascading bonsai compositions.