How to Thicken a Juniper Bonsai Trunk
The art of bonsai is centered around creating miniature trees in ornamental pots. To achieve this successfully, there needs to be a good balance between your surface roots (Nebari), trunk, and canopy.
For many bonsai enthusiasts, this means finding ways to thicken your tree trunk to create this balance and also to make your bonsai appear much older. In this article, we will cover the best ways to thicken a juniper bonsai trunk.
Why Do You Want to Thicken the Trunk of Your Juniper Bonsai?
Thickening a bonsai trunk is an important step in the art of bonsai. The trunk is a significant part of the bonsai. The trunk helps define the style of the bonsai, whether it is feminine or masculine, and also gives the illusion of a much older tree. As the trunk becomes thicker, it gets more personality.
The texture becomes more pronounced, the bark becomes more defined, and the trunks might even become gnarled in some cases. The same can be said of Junipers. Junipers are one of the species that get a great texture on the trunk as the trunk gets thicker and starts aging. This texture creates great visual interest.
Ways to Thicken Your Juniper Tree Trunk
There are a few different ways that you can start to thicken a Juniper bonsai. Some of these techniques work best when used simultaneously. However, it’s good to practice patience as these techniques can take a few years to get to the desired thickness.
That’s why it’s essential to choose trees that already have a decent-sized trunk to work with or be prepared to give the tree the time it needs to develop the trunk’s circumference.
Method 1: Growing in the Ground/Large Container
This is the best method to thicken a Juniper bonsai or any trunk for that matter. If you plant your tree directly into a small bonsai pot, that will severely limit the growth of your tree and thicken your trunk will take much longer. For this method to work effectively, you will need to plant the tree directly into the ground or in a very large container and leave the tree to grow freely.
This means no pruning, root, foliage, or otherwise. Just allow the tree to grow naturally. If your tree is healthy and has enough space to grow, you could see a thickening of up to ¼ inch a year in Junipers.
Method 2: Sacrificial Branches
Using sacrificial branches is another way that you can thicken a Juniper bonsai. These sacrificial branches are usually a few of the lower branches that will not be part of the final design or style but are kept to draw nutrients into the trunk and assist the trunk in thickening.
This method works particularly well when paired with the first method of growing your tree in a large container or directly in the ground.
Method 3: Supplement
Another way that you can thicken a Juniper bonsai is by supplementing it with silica. Silica helps to alleviate stress in your tree and also helps to fortify the cell walls of your tree. You would use silica just as you would your fertilizer.
Since it helps to alleviate stress, it’s especially useful after you’ve worked on your bonsai. This can include after repotting, root pruning, or structural pruning.
Things to Bear in Mind
When it comes to most Junipers, there are a few things that you need to bear in mind when it comes to thickening your trunk. Although Junipers are pretty hardy and a great tree, especially for beginners, it is essential to know that Junipers do not have new growth from the woody plants. They only produce growth from the greener tips of branches, trunks, and stems.
As such, there are specific techniques that will not work to thicken a Juniper bonsai. These include splitting the trunk, cutting down the trunk, and even intentional scarring. Even using tourniquets to induce swelling to thicken the trunk is not recommended with Junipers as scarring, cracks, and such will never heal completely.
If you want to thicken a Juniper bonsai, going the natural route will show the best results. Planting your Juniper directly into the ground or a large container and allowing it to grow out, maybe with a few sacrificial branches, will lead to a healthier tree with a nice thick trunk in a few years.
You can also consider adding a few supplements along with fertilizer to keep the tree as healthy as possible and promote growth. After all, an unhealthy tree will not grow or thicken, so keep the tree’s health your top priority.