Copper wire is used for bonsai wiring when more holding strength is needed than aluminum wire can provide. It is often used on pines and junipers. Choose the thickness according to the stiffness of the branch and how easily you can apply the wire.
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Uses and materials / Wire thickness / Wire options / Use and storage
Copper Wire and Aluminum Wire: When to Use Each
Copper wire for bonsai is annealed to make it soft enough to apply. It hardens as it is wrapped and bent, helping to hold branches in their new position.
Aluminum wire is softer and easier to work with, making it useful for your first attempts at wiring and for smaller branches on deciduous trees. Choose between the materials according to the stiffness of the branch and the holding strength needed, rather than the tree species alone.
Read the aluminum wire guide →
Choosing Copper Wire Thickness
Use copper wire roughly one-third the thickness of the branch as a guide, then check whether it can hold the branch in position. The thickness needed varies with the stiffness of the branch and the bend you want to make.
Copper wire may be labeled in millimeters or by gauge. Higher gauge numbers generally indicate thinner wire, but systems such as AWG and SWG use different measurements. Check the diameter in millimeters when comparing products.
Copper Wire Options
| Product | Available sizes | When to choose it |
|---|---|---|
| Cooksongold Annealed Copper Wire | Selected diameters: 0.3–2.0mm 3–15m, depending on diameter | Trying a thickness in a small quantity |
| Eurowire Annealed Copper Bonsai Wire, 500g | Selected diameters: 0.5–5.0mm 500g | Replenishing a thickness you use regularly |
Cooksongold Annealed Copper Wire — Small Packs
Annealed bare copper wire available in selected diameters from 0.3–2.0mm. Pack lengths vary with diameter: 15m for 0.3–0.4mm, 7.5m for 0.5–1.0mm, and 3m for 1.2–2.0mm. This is useful for trying a thickness without buying a large roll.
View the small copper wire packs on eBay →
Eurowire Annealed Copper Bonsai Wire — 500g
A 500g pack of annealed bare copper wire, with selected diameters from 0.5–5.0mm. It is useful for replenishing a thickness you use regularly or wiring several trees. Select the diameter you need on the product page.
View the 500g copper wire on eBay →
These two listings are for UK delivery. For other shipping destinations, diameters, or pack sizes, browse annealed copper bonsai wire on eBay →. Check the material and shipping options on each listing.
Using and Storing Copper Wire
Choose when to wire according to the tree species and its condition. Anchor the wire securely, for example around the trunk, and wrap it around the branch at roughly a 45-degree angle. Support the branch as you bend it gradually. Copper hardens as you work it, so avoid repeatedly bending it back and forth.
Check regularly for branch thickening and remove the wire before it cuts into the bark. Decide when to remove it according to the tree’s growth, rather than a fixed number of months.
Use wire cutters suited to the copper wire’s diameter. Cut each turn and remove the pieces gently; unwinding the wire can damage branches and buds. Used copper wire has hardened, so avoid reusing it for wiring without re-annealing it.
Keep unused wire organized by thickness, with labels showing its diameter or gauge. Use suitable wire cutters rather than scissors intended for branches and foliage.
Watch the video below for a practical example of bonsai wiring.
