To create your desired bonsai tree style, wire is used to train the direction of branches. The appropriate thickness of wire is coiled around a branch, then the two are bent together into the required position to allow the branch to thicken. The wood then becomes more dense making the branch hold it’s new shape once the wire has been removed.
So, firstly what wire is best to use? Traditionally annealed (softened) copper wire is used for all conifers due to it’s strength while using aluminum wire for deciduous bonsai. In the west, aluminum wire is more commonly used as it is cheaper and can be doubled up if necessary for added strength.
To anneal copper wire, it must be heated until red hot and then quickly submerged into cold water for a few seconds. Coiling the wire around the branch and bending the two together will harden the wire and in turn greatly increase it’s strength.
It is best to practice wiring on a twig off cut from a garden shrub to help gauge the appropriate wire thickness and necessary force to shape the branch.
When you are ready cut a piece of wire one-and-a-half times as long as the branch you wish to shape.
Firmly anchor the branch with the wire by coiling the wire at least twice around the trunk or the parent branch. Begin coiling the wire around the branch roughly at a 45 degree angle.
Hold each turn of the wire with one hand while you coil the next to avoid exerting too much pressure on the bark.
Bend the branch by using your thumbs as fulcrums on the inside of the curve and spreading the pressure of your fingers along as much of the branch as possible. Bend in stages, listening carefully for cracking bark at which point stop. If the branch has still not achieved the desired position, return to it every two or three weeks and bend it a little further until you are satisfied.
It is essential to check the branches regularly, especially at the top of the tree where the growth is strongest. When the wire seems to be biting into the bark it should be removed immediately, however if the branch is not yet set then re-wiring it is suggested but in the opposite direction to minimize damage to the bark. Wire should ideally be removed by cutting it delicately piece by piece as to prevent any tearing to the bark.
– Always work outwards from the trunk, never inwards from the tip of the branch toward the trunk
– If a second wire is required, it should be applied in the same direction as the first.
– To avoid scars, prevent wires from crossing as it will create pressure points.
– Generally speaking young deciduous shoots and twigs can set within a month, while a springy conifer branch can take several years.
1. Wire should be coiled at a 45 degree angle and touching the bark but not tight enough to bruise.
2. If you need to reduce the thickness of the wire further along the branch/trunk, then overlap the lighter wire a few times to anchor the thinner wire before continuing along the branch.
3. For a single branch, anchor the wire firmly by coiling it around the trunk several times.
4. To further increase the anchorage, wiring can start by coiling around a nearby branch and then in the same direction coil through each ‘fork’ and around the branch to be repositioned.
5. Similarly to above, one piece of wire can be used to shape both arms of a fork, coiled in the same direction.
6. In this image, two parallel wires have been used to shape the thick part of the branch. One is diverted to shape a side branch while the other continues along the main branch.
7. To bend the wired branches, lever the two using your thumbs but be careful not to bend too sharply at first.
8. Once the branch has set or the wire has become too tight it should be removed. Wire should be cut off rather than unwound to risk damaging the bark
Bonsai Wire cutters
You could just use standard hardware store cutters to help apply the wire to the tree, however when it comes to removing the wire further down the track it is wise to use proper Bonsai wire cutters to get close to the trunk/branches without damaging the tree.