Objective Pruning of a Bonsai

In this upcoming series of lectures here, we’re going to talk about everything surrounding pruning. So we’re gonna cover all sorts of things, all sorts of species here. We’re going to take a look at some of the most popular species in these tutorials including Japanese maples, trident maples, hornbeams, junipers obviously, and pines.

but our goal here is to kind of breakdown the various stages of development of a bonsai from very young material, to fully finished material that can go in an exhibition because as you’re starting to prune your trees working with younger material there are going to be ways that you approach pruning with those that’s going to be very different from trees in say middle stages of development versus later refinement.

So perfect example here, we’ve got a Japanese maple that has a little bit of wire on it. Obviously no branching on it, but our goals with something like that are going to be vastly different than our goals with a tree like this trident maple here that is fully developed and ready to go in an exhibition.

So coming up here, we’re going to dive into all those aspects of sort of objective pruning I would call it that are going to get you to a really good end goal, I think, in the shortest amount of time.

All right. So first things first here, let’s dive into those three stages of development a bit deeper. So the first stage of development is going to be sort of early stages of development, meaning: working with seedlings, cuttings, air layers, very young material where the primary goal is to develop the primary structure of the tree.

Now what I mean by primary structure is the primary line of the trunk for example and potentially the primary lines in the branches. So there are certain things that we’re doing at this stage of development and by the way, this tree right here would fall into that category.

So what we’re trying to do here is, say for example, thicken the trunk. Now one way we do that is by allowing terminal growth at the top of the tree to elongate for an extended period of time. If we allow a terminal shoot to extend it’s going to create more and more tissue around the trunk and actually thicken the trunk of the tree.

So, you know, when a tree is early in development, say you’re working with a seedling or a cutting typically you’re working with something that might be the size of a toothpick or maybe a pencil. But if your end goal is to get that trunk to say two or four centimeters say two inches, or three inches, something like that you’re going to want to allow that terminal shoot to grow.

And this is applicable to not only deciduous material but also coniferous material as well. Really, all plant species need to have that terminal shoot elongated to put on that thicker tissue. Now at some point down the line when the trunk at the base is as thick as you want it to be you’re going to need to reduce the height of that trunk to turn it into a smaller bonsai.

Now this might sound like trunk chopping but I’m not necessarily advocating for full on trunk chopping here. What we’re trying to do is grow the trunks out to a thickness that’s desirable cut those branches back or cut the trunk back to a new bud that’s moving in a new direction but we want to make sure we’re doing that at a point where we’re not going to create a scar that’s too large on the trunk.

So typically for me when I’m dealing with deciduous material like Japanese maples, like this tree right here I want the trunk to get somewhere between say one to maybe up to max three inches which is going to be about two centimeters up to about six centimeters or so and then we can chop it back.

Anything larger than a six centimeter diameter wound on a smooth bark tree like a Japanese maple, is going to be very hard to heal over in the future. So you definitely want to think about the future size of the plant that you’re trying to build how tall do you want it to be; that’s going to dictate how low you’re going to cut back that first go around to create movement in the trunk.

So again, if you want to make a shohin sized tree for example you might be cutting back to just a couple inches or you know, three or four centimeters above the ground down down here and that may be all you need, and then you can grab a new shoot to create that new line in the plant.

But really the whole point here is for this early stage of development. We’re talking trunk thickening, branch thickening creating those primary lines in the trunk utilizing wire. Also utilizing cuts, like we just mentioned here.

Kind of a clip and grow approach to developing those lines. All those things will fall into this early stage of development. All right. So, you know moral of the story here for those early stages of development is essentially we’re just letting the plant grow.

We’re not doing a whole lot of pruning until it comes time to cut back the trunk, and again develop that new line. Now moving on to the second stage here from early development to mid development. This is where we’ve already got the primary structure set up, both the trunk and the branches and we’re moving into developing the secondary structure.

So essentially the first set of bifurcations across the primary branch structure of the tree. And of course we do this through pruning. And this is going to vary depending on the species; how you actually approach the pruning process to develop that ramification.

So in a previous tutorial here in our intermediate course on Bonsai Empire we talked about alternating leaf pattern trees, opposite leaf pattern trees and world leaf pattern trees. So I recommend that you guys go and check that out as review there to really understand what we’re diving into a little bit later here when we get into the case studies.

But essentially the way we prune is going to be dictated by the phyllotaxy or leaf pattern of the tree. and that’s going to dictate how that ramification is then developed on the plant. So developing the secondary structure on the tree can take anywhere from one to three or four years depending on the species, and depending on the rate of growth.

So most deciduous plants are going to develop pretty quickly so for example hornbeams, trident maples, we’ll say flowering apricots, stewartia plants like that that can be pruned back and will put out multiple flushes during the course of a growing season.

You can develop that secondary structure usually within year, or maybe two years. When you’re talking about something like Japanese maple on the other hand pruning back in either early spring as the new buds are starting to emerge or letting everything flush and then cutting back typically is not going to induce a second flush of growth in that same growing season.

So developing the secondary ramification on a plant like that can take a significantly longer amount of time sometimes. So you definitely need to understand that. We don’t want you to get frustrated when you’re working with certain species.

You just got to know what the growth habits of the plants are. Now when it comes to coniferous material in that mid-stage of development again we’re trying to develop ramification here but the way that we do that through pruning is going to be slightly different of course depending on the species.

So for example if we’re talking about Pines we’ve got two kind of big broad categories of Pines. We’ve got single flush pines and double flush pines. Now double flush pines are those that we can decandle in the summer and they’ll produce, reliably, a second flush of growth with more budding.

So we can increase the ramification on those very very quickly. And if you’re interested in learning more about the decandling process in detail I recommend again that you check out the intermediate course here on Bonsai Empire.

We cover all aspects of decandling, and also needle-plucking in that as well. Now the other category of pine is going to be your single flush pines and those are pines that we cannot decandle in the summer and therefore cannot induce a second flush of growth.

So developing secondary branching on those in this stage of development here, is a little bit more difficult. We actually have to induce back budding on those plants through heavy fertilization and also through heavy pruning later in the summer.

So the timing for working on single flush pines is going to be a little bit different than the double flush pines, and we’re going to talk more in detail about this when we get into our case studies a little bit later here.

Now the other type of conifer that’s going to be very common that you’re going to run into is going to be, obviously, your junipers. So developing junipers is actually very very easy. So we can develop ramification and really full pads is what we’re trying to develop on junipers in a very short amount of time.

So junipers in the spring will flush out We usually do the first cut back in, at least in the northern hemisphere here, in early June. Then we get another flush of growth in the middle of summer. Then we can cut back towards the end of summer one more time, usually early September.

and then we get kind of a small fall flush again which means that we’ve got three full flushes of growth in a single season on junipers: spring, summer, and early fall. So you can increase the density and the ramification on the juniper threefold in one growing season So it’s very very quick and easy if you follow the proper pruning techniques to develop a fully padded juniper.

You can take a young whip, or you could take a newly collected yamadori from the mountains and get it show ready in a very very short amount of time as long as you’re keeping up with the pruning process on a yearly basis.

Of course, we’re going to cover all of this in the upcoming tutorials here. Okay, so this brings us to what I would consider the third stage in building a bonsai and that is the refinement stage. So this is where we shift over from developing the secondary branches to developing the tertiary branches meaning essentially the fine branch ramification on our trees.

So this trident maple right beside me here is obviously well into that refinement stage at this point. So you know, the way we fertilize is going to shift the way we prune obviously is going to shift here as well.

We’re trying to slow the growth down, trying to produce very tight internodes on the plants trying to produce a smaller leaf is possible so that we can essentially just maintain the shape that we’ve created over the last number of years.

And with junipers for example, like I said, they’re very fast, so this could be you’re developing the tree from a small cutting to a fully refined tree in just a handful of years Whereas when you’re talking about deciduous material to get to something like this from an air layer or a cutting is going to take you probably 30 years.

It’s a very different time frame. But as long as you’re applying the proper pruning techniques on a yearly basis it will yield you this type of result.