Wiring basics

by Pieter Janse van Rensburg

"Wiring has two purposes: to help the tree attain its ideal form and to correct over-lapping branches so that all can receive the sun and evening dew" - Saburo Kato.


Copper wire has been in use as a shaping aid in bonsai since early in this century (+-1910). Copper wire should be annealed in a low heat fire to make it soft and workable. Traditionally rice straw was used, but paper or cardboard will work as well. Heat to a dull red colour and leave to cool.

Copper has better holding power, so thinner wire can be used to shape a branch or trunk. Copper weathers quickly to become unobtrusive. Copper wire can be annealed several times so is quite economical to use.

Japanese aluminium wire is widely used in bonsai today. It is made of a special alloy to give it flexibility and holding power. It is available in a very pleasing copper colour, or plain silver. The copper anodizing protects the wire from oxidizing, the plain wire gets a salty deposit on the surface, especially near the coast. Aluminium wire cannot be annealed by the hobbyist. It is easily straightened for re-use by pulling it over the edge of a piece of scrap wood. It has less holding power than copper wire so thicker wire is usually required to accomplish the same purpose.


Choosing the correct thickness of wire is something that comes wnh practice. For minor changes of direction thinner gauges of wire will suffice.

Major changes in direction will require heavier gauges of wire. The flexibility of the species will also influence the gauge of wire to be used. Two thinner wires run side by side will sometimes give better results than one heavy wire, because the contact area is far greater. If one has grossly underestimated the gauge of wire, and a second wire will not secure the limb in the desired position, consider the use of a guy wire.


This technique is widely used on nursery trees, cuttings and seedlings, because they are still young and flexible enough to be bent. The wire should be anchored by pushing one end into the soil. Proceed by coiling the wire at an angle of 45 degrees around the trunk (Fig 1). The branches of a one sided tree can be spread as the trunk is wired by twisting the trunk as one wires. Consider which way the trunk will be twisted and wire in the same direction to ensure that it stays put. If one wants to bend the trunk in any way, always bend over one's thumbs to prevent cracking.

wiring fig1Fig 1. Trunk wiring


When wiring main branches it is advisable to wire branches in pairs. The branches should be spaced sufficiently to allow at least one and a half turns around the trunk. This will allow the two branches to be bent without one having a counter-effect on the other. Before applying wire to a branch there are two things to consider that will determine the position and direction in which the wire is to be applied. If the branch is to be wired up, the first coil should pass under the branch (Fig 2).

wiring fig2Fig 2. Wiring branches upwards

If the branch is to be wired down, the first coil should pass over the branch (Fig 3).

wiring fig3Fig 3. Wiring branches downwards

If the branch must move backwards, the wire should be coiled clockwise. The coils will pull tighter as the branch is moved backwards, and enhance the holding power of the wire (Fig 4).

wiring fig4Fig 4. Wiring clockwise takes branches backwards

The opposite of course holds true for branches to be moved forwards (Fig 5).

wiring fig5Fig 5. Wiring anti-clockwise pulls branches forward

Refer to Fig 6 for wiring alternate branches, always bearing in mind whether it is to be bent up or down, moved backwards or forwards, to determine the position and direction of the wire.

wiring fig6Fig 6. Alternate branches

To wire opposite branches refer to Fig 7. Note how the wire is coiled one and a half times around the main trunk.

wiring fig7Fig 7. Opposite branches

For wiring forked branches refer to Figs 8 and 9. This is a good technique for wiring branchlets to create a fan-shaped branch. When wiring secondary branches, follow the main wire back to the trunk. Always try to wire branches with one wire. A good idea to check the route a wire should follow, without crossing another wire, is to try it first with a piece of string.

wiring fig8Fig 8. Wiring forked branches

wiring fig9Fig 9. Wiring fork branches with one wire


  • Trees with tender bark should be protected from wire by wrapping the wire with florist's tape, masking tape or raffia. l.V.-tubing works well for wires up to about 2,5 mm in diameter.
  • Let the tree dry out somewhat before wiring.
  • Never wire a sick tree.
  • Avoid wiring shortly after repotting.
  • Keep the tree sheltered for a few days after wiring.
  • Wait 2-3 weeks before fertilizing a tree after wiring.
  • Give it a good soaking and/or sprinkling after wiring.


Make a slight incision on top of the branch where the branch emerges from the trunk, tear the branch away from the trunk, seal and wrap with tape before wiring in place. As the scar heals, the branch will set in place. Another way is to cut out a wedge on the underside of the branch before wiring it down.

I would like to close with another quotation, this time by Yashiroda. "Never be in a hurry .......... it is the hands which must do the learning, slowly and repeatedly until they can think for you."


Have fun.


  1. Bonsai, its Art, SCience, History and Philosophy by D Koreshoff.
  2. Bonsai Today No 1, May-June 1989

Related Articles

Contact Us

We would be happy to hear from you should you like to find out more about the club, meetings or bonsai in general.

Send us a mail

Year Programme

We have an exciting calendar of club meetings, events and public exhibitions planned for 2017/8.

Learn more


Fearlessly he moulds and

guides the elm tree

to a greater masterpiece

Random Bonsai Tip

When creating Ishizuke or a rock clinging bonsai planting there must be harmony between the tree and rock, that is, the style of the tree and the shape of the rock must have artistic harmony and it must be natural.