One of the main and most important techniques to learn and master when growing a bonsai tree is wiring. This is the primary way in which you train and style your Bonsai trees. The wire that is wrapped around the branches allows you to bend and reposition the branches to your desired shape. It will take a few months for the branches to set in their new position, and it is important to remove the wire once the branches have set and replace it with a new, thicker wire as needed.
When to wire
You can basically wire your trees at any time of the year, while deciduous trees are easier to wire in late winter after they defoliated. You should start wiring your tree when it is strong enough and its trunk and branches can handle the bending process. Keep an eye on your tree regularly as the branches can thicken fairly quickly during the growing season and the wire will start cutting into the bark. Make sure to remove the wire when needed.
Which Materials are best for wiring
The two most common materials that are used to wire Bonsai trees are here are Anodized Aluminum and Annealed Copper. While both materials are good to work with, easy to bend and manipulate, it's usually recommended to use the Aluminium for wiring deciduous species and the Copper which is harder, for pines and conifers.
A Rule of Thumb is to use a wire that is 1/3 of the thickness of the branch you are wiring. The wire should be thick enough to hold the branch in its new position.
You can find wires from 1mm to 8mm and it's recommended to start with the 1mm- 2.5mm for younger trees, with thinner branches.
When wiring thick branches with stronger, thicker wires, you may think of using some protective layer to prevent the wire to cut into the bark when shaping it. Raffia, which is a palm fiber, is one material that is easy to find and can do the job when soaked with water and wrapped around the branch.
How to Wire a Bonsai tree - Basics
Before bending and shaping your tree's branches it's important that you wire all the branches you intend to shape. When wiring the entire tree start from the trunk and work upwards to the primary branches, and then keep going to the secondary branches.
When you see possible, use the "double wiring" technique in which you wire two branches that are near each other, and with similar thickness, together, using the same piece of wire, to provide more support.
When this is not possible use the "single wiring" technique.
When possible, select two branches that are near each other and are similar in thickness.
Before getting to wrap the branches, wrap the the wire around the trunk twice so it will not move when bending the branches.
Cut off the wire in the length you need to cover the branches.
Start wrapping the wire around the trunk. Wrap it twice and proceed with one branch at a time. Start from the base down all the way to the tip. Then move on to the other branch.
When wiring make sure to wrap in a 45-degree angle. This will allow the branch to grow thicker while keeping its shape.
To bend a branch DOWNWARDS from the trunk - wrap the wire from below the branch.
To bend a branch UPWARDS from the trunk - wrap the wire from above the branch.
Start by cutting off the correct wire length to wrap around the trunk twice and move up from the branch base to its tip in a 45-degree angle.
Try to wire additional wires neatly beside each other while trying to avoid crossing wires as much as possible.
In some cases there is a need to bend and shape downwards branches that are old or too thick to be bent with the wire. To do this we use the guy-wiring method.
The guy wire needs to be about 1mm thick wire, and anchored safely on a sturdy, solid location, such as the pot, a strong surface root or a strong low branch.
Before wiring and bending down your branch make sure to protect it with a small piece of rubber, cloth or plastic, placed folded on the branch. Then make a hook from a small 1" piece of thicker wire and place it on top of the protective layer.
Once you have the hook, connect your guy-wire to the hook and anchor it to the chosen spot and gently bend it into place.
How to bend the branches
After wiring the entire tree or the desired branches, it's time to start bending and repositioning the branches to their new shape.
Hold the branch you want to bend on the outside with your fingers and bend the branch from the inside of the curve with your thumbs. Apply force on the inside of the branch to reduce the risk of splitting or breaking it. After reaching the desired position, don't move the branch or try to bend it again as it will likely harm it.
How to care after you wire
Wiring and bending a tree can be quite a stressful experience. After wiring and bending your tree, place it in a shaded area, water it and fertilize it to allow it to regain its strength.
Keep a close eye on your wired tree to see that it doesn't grow too fast and the wire will cut in the trunk and branches, damaging the bark, leaving permanent scars. Once you see the tree grows in the wire and before they start digging into the bark, remove your wires by cutting it on every turn. Do Not try to unwind it back to recycle the wire - as it will most likely harm your tree.
Wiring might not be the easiest thing to do but practice it and you will eventually master it and in no time you can shape your tree to that perfect shape, exactly as you imagined it to be!