How to Wire Bonsai Tree The Right Way

A wiring technique in bonsai is used to better control and manipulation the structure of the tree. We use wiring to fill in bare spots of the tree, create a movement or simply to change the direction of the branch.

It would be very hard, and sometimes even impossible, to create a bonsai that we want without using a wire.

Correct wiring is almost an art form in itself and takes a lot of practice to get it right. If the tree is wired nicely, you can display it without wire being an issue.

Wire Types

There are two main types of wire used for bonsai: aluminum and copper. Aluminum wire is not as strong as copper, but easier to apply and easier to remove. It is better for beginners because it is much more forgiving than copper.

Although aluminum wire can be reused, I don’t recommend it, because you might damage the tree during unwinding process. Since copper wire is much stronger, you can use thinner pieces. Copper wire is more difficult to apply and cannot be reused.

I personally like to use brown anodized aluminum wire. It is inexpensive and easy to use. Anodized coating protects the wire from corrosion while brown color helps it to blend in with the bark. This is a great wire especially for beginner.

Wire comes in different thickness from 1 to 8 mm. To wire a whole tree, start by getting reels of 1.0 mm, 1.5 mm, 2.5 mm and 4.0 mm. Generally, for the wire to hold you need to use a wire of 1/3 of the thickness of the branch/trunk you are wiring. If the wire is too thin, it will not be strong enough to hold the branch in the new position.

How to Wire

When wiring the whole tree, start with the trunk and then move to the main branches and then to the secondary branches. The wire should be applied at 45º degree angle.

If the angle is more than that, the wire will be too open to have enough holding capability. If the angle is less than 45º degree, the wire coils will be too tight which can result in sap flow restriction and ultimately the death of the branch.

You also want to make sure the wire is not too loose; otherwise, it will not have any effect on the branch.

Use the trunk or close-by branches as an anchor for the wire. If you are wiring the trunk, anchor the wire by pushing one end into the soil and the roots of the tree. Try to use one wire for both nearly positioned branches if they are of similar thickness.

To make sure you have enough wire, make it 1/3 longer than the branch you are wiring. Try not to wire across the front of the tree when using one wire for both branches. Hold the wire firmly with one hand and coil it carefully around the branch towards your body.

Start wiring at the point where the branch is growing from the trunk and go down to the very tip making 45º degree coils. The LAST coil should be secured at the very tip at a 90º degree angle.

If you are trying to bend the branch down, wire over the top. When you come across the branch or a leaf while wiring, go around them. You never want to cross the wires.

So, when you are wiring smaller branches and you already have a wire on the main branch, apply it in between the coils of the main branch. When you reach the end of the branch, cut the excess wire with the wire cutters.

If you are working on a fast growing tree, leave a little bit of room between the wire and the bark. Don’t make coils too tight to ovoid wire cutting in. The thicker the branch, the harder it is to bend without it cracking.

Use both hands when bending the trunk or the branch. Go SLOW and listen for the sound of splitting or cracking. It is better to bend a thick branch in multiple steps over time than doing it at once.

To prevent branch from snapping, test its tension prior to wiring. Some species can be wired only when they are young. With age, the branches become ‘hardened off’ and it is impossible to bend them without snapping. Some of those trees are Azalea, Bougainvillea and Acer palmatum ‘Kiyohime’.

Although bonsai trees respond very well to wiring, it does cause a certain amount of stress. So, DON’T wire sick or weakened trees as it might slow the recovery. Wait for it to get healthier before applying the wire.

Best time for wiring

The BEST TIME of the year for wiring your bonsai depends on the species of your tree and the climate it is growing in. Many believe that most of the species can be wired during any time of the year. From my experience, there is a particular time of the year that is better than other.

Pine – The best time of the year for pines is late fall or early winter when the sap is not flowing and the branches are more flexible. By the end of summer, the increase of branch thickness will be over and wiring after this time will allow you to keep the wire on for a full year.
Deciduous – Could be wired anytime from early spring to early fall. In spring, it is easy to wire because you can see the branches. While wiring, be careful not to disturb any of the buds. Wait till the tree loses all the leaves before wiring in the fall. That way, you will be able to see the structure of the tree better.
Coniferous – Can be wired from middle of the spring to late fall. Keep in mind, coniferous will heal faster during growing season than any other time of the year. If you decide to wire in spring, you will need to rewire the tree after the new growth develops.
Tropical species – Since they don’t have dormancy period and are always growing, you can wire them anytime of the year. Before applying the wire, defoliate the tree so you can see the branch structure. It is much easier to apply the wire when there are no leaves.

When to remove the wire

You always want to remove the wire before it cuts into the bark and leaves an ugly scar. Therefore, check your tree often especially during the growing season.

Some of the tropical trees grow so fast, that there is almost no way of avoiding the marks. Light marks will heal within a year of two, so there is no need to worry. Severe marks might never heal leaving awful scars.

When removing the wire, always use wire cutters, because they have round heads that are specially designed to cut the wire clean without damaging the bark of the tree.

Some bonsai enthusiasts, in order to save money, like to unwind the wire and reuse it. I learned the hard way that it is a bad idea. There is a chance of damaging the buds, leaves or branches. You can try reusing a larger more expensive aluminum wire, but don’t try to unwind copper wire.