Are you thinking about growing bonsai in your home garden? If so, you might want to learn all the steps involved in pruning bonsai to perfection.
Pruning? Don’t bonsai trees just naturally grow in their dwarfed, compact fashion?
Not necessarily. Although there are some bonsai species that are propagated and cultivated from genetically dwarfed species, in most cases, bonsai trees are just normal plants. They are pruned and trained to grow in their miniature form.
Because of this, you can grow just about any kind of tree in the bonsai tradition - it’s all about knowing the right styling and pruning techniques.
Here are some tips.
Bonsai Pruning Guide: The Basics
Knowing how to train and prune bonsai regularly is important. There are several kinds of pruning you can do, including maintenance and structural pruning. While maintenance pruning helps you refine and maintain the existing shape of your tree, structural pruning is a more rigorous style of pruning that will give it a more basic shape.
Why prune? There are several reasons why this is important. For starters, trees like to grow with the central stem growing more dominantly than the side stems. This encourages trees to grow taller so they don’t get shaded out by competing trees. However, this is not a desirable trait for bonsai - you want all the branches to grow well.
Pruning can help you control that natural tendency.
How to Prune a Bonsai Tree
Here are some bonsai pruning guide tips so you can prune your bonsai trees perfectly - each and every time.
1. Pruning for Maintenance
Maintenance pruning will help you maintain the shape of your tree, reducing the likelihood of excess growth on the outer and top parts of the stem and instead encouraging growth closer to the interior of the tree. Maintenance pruning can be done at any time during the growing season, which can be year-round for indoor-grown plants.
For outdoor bonsai, it is best to prune sometime between March and September.
To prune, start with a sharp, sanitized pair of shears. Some bonsai trees, like pine trees and conifers, can be pinched off by hand instead of being trimmed with scissors - clipping with scissors on these softer plants can cause them to develop dead, brown foliage. Simply press the tip of this hoot between your forefinger and thumb, then gently pull it away. It should snap freely.
For most other bonsai trees, you can use your scissors to snip the shoots and branches that have overgrown the desired canopy shape. Never cut more than a third of the plant at a time.
2. Structural Pruning
Structural pruning can be done in the early spring or late fall. The best timing will vary depending on what kind of bonsai tree you are growing.
Remove all dead branches and figure out which other branches should be trimmed to achieve your desired shape. You can remove unwanted growths like:
- Crossing or hanging branches
- Those that are returning to the tree’s center
- Suckers on the base of the trunk or higher on the trunk (also known as water sprouts)
- Branches that compete with the trunk or grow from the same height
- Branches that are disproportionately thick at the top
Again, do not remove more than a third of the plant at once. If you prune a section of thick branches, you might want to use concave cutters to reduce the effect.
After pruning of any kind, take the time to seal up any wounds you inflicted, using cut paste. You can purchase this at most specialty bonsai shops - it will help the tree heal faster and prevent any infections in the meantime.
This kind of pruning can be done more or less year-round but structural pruning should be restricted to just once per year, either in the spring or in the fall.
3. Wiring Bonsai
Wiring is not exactly the same as pruning but also must be done if you want your tree to keep looking healthy. Most species of bonsai trees can be wired at any point but deciduous trees are easier to wire in the late winter, since they won’t have any leaves. If you choose to wire, keep an eye on your plant during the growing season - the branches can grow quickly and cause scarring from the wire digging into the bark.
You can use several types of wire on your bonsai trees - both anodized aluminum and annealed copper work well. Aluminum is best for deciduous species while copper is better for pines and conifer. Choose a wire that is 1 to 4 mm thick.
Wiring is a tricky technique to master. If you can, start by wiring two similarly-sized branches that are near each other, using a single piece of wire. Known as double-wiring, this technique will give support to both branches. Other branches can be wired independently.
Start from the trunk and work your way up to the primary branches before starting on the secondary branches. Wires should be ⅓ of the thickness of the branch you are working on, which will help hold the branch in place. Wrap the wire around the trunk and proceed with a single branch at a time, wrapping at a 45-degree angle so the tree grows thicker while maintaining its shape.
Once you have wired the entire tree, you can bend and reposition the branches to your liking. Don’t move a branch once you have it where you want it - this can damage it.
After you write, put your tree in the shade and fertilize it as you normally would.
Other Bonsai Styling Techniques
There are many other bonsai styling techniques to consider for your plants, too. For example, you can do bonsai defoliation, which involves cutting all of the leaves of a bonsai tree, typically during the summer months. This forces a bonsai to develop new leaves, making the leaves smaller overall and forcing more energy into root and branch development.
You can also create deadwood on bonsai. This is a unique technique that can be a bit challenging to do without killing or injuring your tree. However, doing so can dramatically increase the tree’s overall character.
Other methods of pruning techniques and styling your bonsai plants include tending to the trunk, creating a bonsai forest or group planting, growing a rock planting, and engaging in other advanced wiring techniques to create more complicated bonsai art.
Whatever the case may be, caring for your bonsai trees starts with good pruning and wiring. Follow the tips above and you’ll find yourself pruning bonsai to perfection in no time!