Pinching vs. Pruning
Pinching vs. Pruning
Creating a bonsai is truly about building a design structure that is cohesive from the trunkline to the finest branching. In terms of the pivotal points of work across the span of a bonsai’s creation, there are 3 key moments – selecting and developing the initial structure, then growing out and organizing the secondary branches, and finally, working to evenly distribute the strength across the tree to create tertiary ramification.
Building the skills to create intriguing bonsai means understanding not only the techniques, but the arc of progress and stages of development when those techniques are applied to achieve the highest level of aesthetic creation. Developing a cohesive approach of timing, technique, and fertilization to actualize your vision and achieve what you are trying to accomplish sets the tone for what type of growth in each stage of development the tree will give you.
Please keep in mind, every decision we make in the build of a bonsai has both an aesthetic and horticlutural consideration. Never do we make a decision about aesthetics without considering the horticulture and vice versa.
When we refer to pruning, we are talking about using scissors, saws, or concave cutters to make cuts– these specific decisions on manipulating the foliar mass and branching are made per the design goals of the composition. We decide whether to expand or reduce the tree's canopy, leave a branch longer to induce thickening, or cut it back to stimulate strength on the interior part of the tree.
In order to prune a tree, it must be in an energy positive state. In the spring, we see an explosion of fleshy new growth on any healthy tree. Prior to the tree producing growth, it is in an energy positive state with large amounts of stored resources to create new foliage. The tree uses up that stored energy to push out new growth. Once that growth has been produced and begins photosynthesizing, the tree's resources are replenished, getting back into an energy positive state. We should always prune when the tree is in an energy positive state.
"The pinching process is where we can begin to create fine ramification throughout the entire canopy of the tree."
When we refer to pinching, this is a technique of using our finger to pinch off soft emerging growth before that growth ever hardens off. This technique stops the elongation of the internode, or spacing between the leaves, and removes the auxin, or growth hormone, at the very tip of the branch. Pinching allows us to strategically transition energy to stimulate buds on the interior that would have otherwise been suppressed. The pinching process is where we can begin to create fine ramification throughout the entire canopy of the tree.
Understanding the difference between pinching and pruning is essential, but now you need to know when to apply these techniques and why. What follows is the most basic arc of a bonsai's development.
Step 1 – Grow
The first step in the design process for any bonsai is to set the structure, this is also known as the initial styling. Knowing how to handle the structure starts with the trunkline, the most primary line in the bonsai design. Manipulating this trunkline, and identifying that primary line is the rudimentary goal of setting your bonsai’s structure. This can look like making some big bends to set the shape with a conifer, or executing big pruning decisions on a deciduous tree to regain a grown-out silhouette.
After setting the structure, the tree needs to recover and this takes time. Your main focus should be heavy, proper fertilization to stimulate robust, healthy growth that should will turn into secondary branching. Your mantra here should be grow, grow, grow– let the tree get wild.
Step 2 – Grow & Prune
Once the structure is set and the tree has regained its health, it is time to turn your attention to building the secondary branches that emerge from the original structure or trunkline. You now get to manipulate, prune, and wire out this overgrown, healthy branching to create your secondary design, enhancing what was brought forth in the initial, structural styling. At this point, you are continuing to cultivate robust growth and pruning to maintain. You do not pinch during this stage.
Step 3 – Pinch
After setting an impeccable structure, then building up and styling out those secondary branches, your tree should be pushing out healthy flushes of growth off the secondary branching. At this time, the tree is ready to enter tertiary development. When you are cultivating tertiary ramification, this is the point when you begin pinching to transition energy to the interior. Repeat, you should not pinch your bonsai until you are at a stage of tertiary ramification.
So up until this point with your bonsai, you have been focusing on producing healthy growth via fertilization and balance of water and oxygen, then pruning that growth to establish the secondary branching in your design. Once you transition to tertiary ramification, it is important to pull back on fertilizer so you can better control the growth and resources and you’re not encouraging this wild elongation and thickening. You want subtle, thin ramification now, so your fertilization should reflect that.
"These 3 simple stages—structure, secondary, tertiary – and their corresponding actions should be in the mind of every bonsai practitioner."
A common cycle that can be easy to fall into but is ill-advised – let the bonsai grow, then prune back exactly what it just pushed out. It is like treading water in terms of the tree’s design. Each season it puts out energy, and instead of utilizing it or transitioning it, it gets cut off. So the tree maintains a similar structure over time and does not move towards a highly ramified bonsai.
It is important to understand what stage of development your tree is at and what the goals of that stage should be. These 3 simple stages—structure, secondary, tertiary – and their corresponding actions should be in the mind of every bonsai practitioner. The arc of these stages occur over many seasons, it takes patience to build a highly evolved bonsai.
Of course these should be treated as guiding lights, not hard and fast rules. Every tree will have unique needs depending on the season, species, health, and the many other contributing factors. But knowing these general steps for how to properly build branch structure will allow you to take that next step to understanding the nuances to different species, design goals, and horticultural circumstances.