Pruning or trimming a bonsai can seem like an intimidating task. Fortunately, the truth is that anybody can do it. Trimming to take care of your leafy buddy or to give it a kick-ass look shouldn’t be a problem if you use the right tools and follow the right steps.
So, how do you prune a bonsai tree? First, place your bonsai on a table that is at eye level. Look for any dead branches, leaves or branches that are crossing each other that can obstruct the trunk from being viewed. Trim these undesired parts using proper bonsai clippers to achieve the bonsai shape you have in mind. But don’t overdo it, don’t cut more than ⅓ of the bonsai’s foliage per year.
And more questions naturally pop up: Are you wondering which type of clippers you should use? When should you prune your bonsai? Or just curious about how to identify the parts that you need to trim? Keep reading and you will find answers to these questions, in our best practices for bonsai pruning compilation
Some months ago when I got my first bonsai, I remember the guy at the shop immediately gave me a card with basic pruning instructions and a maintenance kit.
I then asked him:
Why do I need to prune my bonsai tree?
Pruning equals health and beauty for you bonsai
Based on this, I decided to dig in deeper. From my research, I have seen that pruning importance varies. Some bonsai owners call pruning “the art of bonsai aesthetics”, while others see pruning as a simple need-to-do task.
I found that the possible reason for these two perspectives is that there are two types of pruning: maintenance and structural.
Maintenance pruning is all about restructuring natural weaknesses in the design to allow your bonsai to grow taller, healthier and stronger.
All trees tend to grow more towards their top branches rather than their lower branches. They seek sunlight, and naturally, the sun is up. This natural phenomenon is called apical dominance, which can be summarized in the leafs’ constant competition for sunlight.
Then, if you add a little of Darwin’s survival of the fittest theory, the top foliage will become thicker and cooler, while inner leaves and branches will get weaker and start to die away. And so the cycle continues.
Why is this important? Because with maintenance pruning you want to counteract this phenomenon and encourage the tree to redistribute its branches to grow more evenly.
This is especially important for your bonsai since it significantly improves its chances of thriving if its trunk gets enough sunshine and airflow.
At the end of the day, bonsai, at their very core, is an artform that aims to defy genetics and its rules, since trees are not meant to be so small in size.
On the other hand, structural pruning is more about trimming specific branches of your bonsai to give it the desired shape you have in mind.
Some practitioners will tell you that the end goal of bonsai design is to try to replicate, in your bonsai, the shape of the original or large-scale version. That’s why, one tip I found useful is to keep a picture of how you would like your bonsai to look in the future, and shape it as you go (isn’t that great?).
Back to the shop story. After learning why bonsais need pruning, I wondered…
When and how often do I need to prune my bonsai tree?
According to research, you can perform maintenance pruning several times throughout the year. However, as with most things bonsai, some species might have specific conditions for pruning, so make sure to ask this in a local nursery to see if your specie applies
Bonsai masters also recommend doing maintenance pruning only during the spring and summer months (from March to September in the upper hemisphere) since this period is the growth season for your little tree.
On the other hand, structural pruning should be done once per year. The reason for this is that it generally involves cutting large branches, which mean serious changes to your bonsai.
In contrast to maintenance, to know when to do structural pruning you will definitely need to consult a guide since it absolutely depends on the species. We found in some books that for most species these changes should usually take place during early spring, however, for some others, it is better to do it during fall.
What do I need to prune my bonsai tree?
Before getting into the action, get a proper pruning kit. Your bonsai needs special care, so don’t try to cut its parts using conventional scissors or the ones that you use to trim other parts of your body (so no nail clippers either). Also, keep in mind that you will need different tools for a mature tree compared to a young one.
General bonsai advice agrees that it’s best to get a concave cutter and a twig shear. These will be enough to do the work.
Fortunately, if there is a misstep during the process, it’s good to know, you can always get some cut paste to cover the wounds after making the cuts (also known as “Bonsai Bandaid”).
But that’s not all! As you will see later, there is a pruning technique that is done with your hands. So don’t underestimate the power of pinching.
Steps to Prune a Bonsai Tree
- When bonsai pruning it’s advised to place it on a table which is at eye level. This is because bonsai trees are meant to be seen at eye level, so it helps to keep the perspective.
- Sit and observe your bonsai. Chill. Maybe play some little music, you might want to turn off your cellphone, so you can focus on the present moment and avoid making silly mistakes.
- Assess the parts that you are going to cut:
- If you are doing maintenance pruning, focus on the top and outer branches, spot those specific ones that need to be cut to allow more sunlight to get to the middle of the tree.
- When performing structural pruning, it might be useful to have the end design of bonsai you want to achieve. In addition, you can use the following checklist of the top candidates for any structural cut:
- Dead branches and leaves.
- Branches that are crossing each other.
- Thick branches that might look disproportionate.
- Branches or parts that are growing too close to the soil.
- Interior limbs that are not going outwards.
- Steadily get to the cutting:
- For maintenance pruning, use the wig shear to cut the branches that you identified in the previous step.
- For structural pruning, you will need to switch between the wig shear and the concave cutter to do the task. This will depend on the thickness and size of the branch.
- Be ready for mistakes. Have the bonsai band-aid at hand: when cutting large limbs, you will cause damage (sorry that’s the truth). As these parts can take time to heal, it is recommended to apply cuts past the wound, this will accelerate the recovery process and help to prevent any disease from spreading.
Some pruning variations:
The “pinching” method:
Remember I mentioned “pinching”?. Indeed, you can prune a Pine bonsai using this method. Because of the fragility in the leaves of this species, it’s better to pinch the leaves by hand instead of using shears. Again, it really depends on your bonsai type.
The defoliation method:
This method applies to the Deciduous tree. It consists of basically pruning all its leaves, while t keeping the stem intact. The magic behind defoliation is that it will result in more new shoots with smaller leaves, which will equal to more future foliage.
Don’t cut more than ⅓ of the bonsai’s foliage per year.
How do you trim a bonsai tree for the first time?
Follow the steps above. If you are afraid (no worries, we’ve been there), go to a local nursery and ask them to teach you how to prune your bonsai.
Can you trim a bonsai tree with scissors?
You can. Not recommended. Would you like to get a haircut with a machete? 😛
Will bonsai leaves grow back?
Yes, that’s part of the magic. That pruning will make your bonsai to grow stronger and good looking.