Wiring Basics

This article derives partially from presentations by Jerry Carpenter

A Few Points to Remember

  • Aluminum wiring should be used on deciduous trees, like maples, because the wire will be removed after just a couple of months to avoid scaring the bark. You may be able to remove aluminum wire and reuse it.

  • Azaleas are also typically wired with aluminum because softer bends are desirable on such trees – and because aluminum doesn’t hold it’s shape as well as copper it is suited for making softer bends.

  • All other trees should be wired with copper.

  • Deciduous trees should be wired as soon as the leaves drop. Without leaves you can see what you’re doing as you wire. You can monitor the wire to make sure that it isn’t digging into the bark. Also the trees grow more slowly when dormant so you’re less likely to leave the wire on too long.

  • Pines should be wired after new buds are large enough that you can see them and not knock them off when wiring. Often around August. Junipers can be wired almost any time.

  • Start by wiring the largest branches (or trunk) first, then put on smaller medium and then smaller wire. This will make it less likely that you’ll cross a wire.

  • Crossing a wire means wrapping one wire on top of another wire. The wire on top can trap the first wire so it can’t shift as the tree grows and you're more likely to damage the bark. In the worst case you can cause visible grooves!

  • Put the wire on from the trunk and wrap the wire around the branch coming towards to you. To do that you need to place the tree so that you are facing the trunk and the branch to be wired is coming towards you – towards the smaller end of the branch. Never wire away from you.

  • It is easier if the branch you are wiring is ponting slightly to the right of your body (assuming you're right handed).

  • Each twist of wire should be about 45 degrees (diagonal) compared to the branch is is around.

Anchor Wire

If the trunk needs movement then the first thing to wire is the trunk. Begin by selecting a wire that is heavy enough to move the portion of the trunk needing to be bent. Anchor the wire by pushing it into the soil near the trunk. Push the wire down so that it touches the bottom of the pot. Make one or two wraps around the trunk (at about 45 degrees diagonal) and then check whether the wire is moving around in the soil.

Movement is bad so if that's happening use a smaller wire around the base of the trunk to hold the wire secure. Movement happens more often when the tree has been newly potted and before the roots have colonized the entire pot. Don't over tighten the wire around the base so that it or the heavy wire digs into the trunk. Check after a month or two and remove the smaller wire before the trunk is damaged.

Wire from pot towards top of tree

If you think you'll need a anchor wire consider putting a length of plastic tubing around the wire where you'll be attaching the tie wire.

Not Too Tight

The wire wrapping around the trunk, or any branch, should be tight enough to move the branch in the direction you want it to go, but not so tight that as the tree grows it will be trapped. Leave a bit of space between the tree and the wire or else you'll soon have marks on the trunk and branch. The space should be on the opposite side of the bend. For example, if you are bending a branch downward then the wire on top of the branch would be tight against the branch, but a bit loose underneath the branch.

Shift to Smaller Gauge When Appropriate

Heavy wire will move and hold larger branches but the bends in large gauge wire will be larger radius than what a smaller gauge wire can bend. Heavy wire is more difficult to bend and work with - and more expensive. So, once you've been able to move the portion of the branch shift to a smaller gauge.

You want the smaller gauge wire to overlap (beside, not on top of) the heavy wire, so make sure you go a bit past where the smaller wire will be used

Stop the heavy wire a bit past where the new wire will applied

Here the smaller gauge wire goes from the top-left branch up to the top. Use same method on branches - heavy wire on main part of branch, then shift to smaller gauge wire when heavy wire not needed.

Here the smaller gauge wire goes from the top-left branch up to the top. Use same method on branches - heavy wire on main part of branch, then shift to smaller gauge wire when heavy wire not needed

On Top or Underneath?

When you need to bring a branch down, put the wire over the top of the branch where it meets the trunk. Likewise, if you want to bend the branch to the left, put the wire over the right side of the branch where it meets the trunk. If you do it the other way then wire will be between the trunk and your bend - you won't be able to move the branch in the direction you want as close as possible to the trunk. Instead you'll have a short section of the branch that is straight and then bend and that won't look natural.