Annual Repotting Update

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It seems that each year since I started this column, over six years ago, that I have written about repotting in the Spring. Since repotting is such an essential part of our bonsai regimen, I thought that I would recap a few things and maybe pass on a few new tips. I just finished teaching several workshops specifically on repotting, with one more to go. Seeing a few common misconceptions, and some really good practices brought a few things to the forefront of my mind. I am sure that you are well into your repotting season by the time you read this. I started just last week – about March 1 on my trees.  

The first point to consider that this is the only time that you get to work on the roots for at least two years. That is for deciduous. For conifers it might be 5 years. The work that you do now has to last the tree for that period of time. We have several times to correct branch structure by pruning, wiring, etc… during any one season. However, this is the only opportunity that we have work on the roots, correcting flaws, changing the soil or container and setting up the health and growth of the tree for the next several years. It’s worth getting it right, to the best of our ability and knowledge.

First and foremost is the aftercare, so I am starting at the end, rather than the beginning. Make sure that you can keep any tree that was repotted this season from freezing, or at least the root portions. It’s also best to be able to keep them out of the rain for several weeks until you see the tree starting to use up the moisture in the container. That means that it has recovered and is ready for the transition to our great Pacific Northwest spring weather. Rain.  

For the first time in 30 years of bonsai, I built a heat bed to facilitate the recovery of plants after repotting. I mention the 30 years, because it is not in any way essential – I have made it fine this far. However, I can tackle the aging and declining root balls of some very old, collected trees with confidence. I started that process last year with great success and am now moving onto harder specimens That may be the subject of a future article. What makes my heat bed a little different is the fact that it is not in a greenhouse, but just out in the open on my patio. I love it already after just one week.

Next up is, have a plan. Do you have all of your soil components sifted and/or mixed and ready to go. Do you have the pots? More importantly, do you have the time? I am finding that just taking a pine from a six-inch pot up to an eight inch, with pruning, etc… is taking me about half an hour at cruising speed. I can’t seem to do a medium size tree in less than two hours. And since most of my trees are larger, you can do the math.  

If you run short on time, wrap the root ball in a wet towel and finish it later – within a day. Or you can heal it into a mound of something you might have, like old soil, bark dust, etc… Just make sure that it’s moist. Once you have the tree popped out of the old container, work on the new one before you start on the root ball. The less time your tree is out in the air, the better.  

If it is going back into the same container, take time now to rinse it out and let it drain and dry. If you know what pot you are going to use, put the drain screen in. The point really is to be looking ahead at what you are going to need to do to finish the repotting. Do you need to sift more top dressing? Do I need chopsticks of a different size? You get the idea.  

My next point is to be gentle. Use a root hook only when necessary and with great care. Slow going with chopsticks or angled tweezers is much easier on the tree. The soil should be moist but not wet. Handle roots with care. You can decide later what to cut off, but if you mangle them, the choice is made for you. And remember that we don’t want to bare root a conifer. It’s chances of surviving, let alone thriving, go down really fast. Also remember that you don’t necessarily have to cut roots to fit them into the pot. If you feel that you need to keep more roots for the health and vigor of a tree, you can simply fold them gently into the pot and address them in another few years when you have more root mass to utilize.

What soil you use is quite the conundrum and I am always seeking to improve what I have for each tree. There is no doubt of the effectiveness of Boon mix for bonsai, a 1:1:1 mix of Lava, Pumice, and Akadama screened to between 1/16 and ¼ inch particle size. But it can be tweaked. And a lot. Take out the 1/8-1/4 for shohin, or the 1/16-1/8 for trees that like it a little drier, like mountain pines. But there’s more. I have mentioned in the past that we can to use up to 100% Akadama on deciduous trees. I am getting mostly favorable results with that – better than the standard mix.  

But then there is Michael Hagedorn who favors just Pumice and Akadama, and our own Dennis Vojtilla that uses Lava and Akadama. They are leaving one component out and you can hardly argue their practice, looking at their trees. So, experiment on what works for you. I just had a workshop with the Eugene club, and their president, Tom Fincel (An outstanding bonsai artist and even better person to get to know) had a large container each of sifted Pumice and Akadama (A student of Michael’s) with which he could easy mix up whatever proportions he likes for any particular tree and I really feel myself gravitating to that approach.

The last thought that I leave you with is what was hammered into me (albeit it gently) by Boon. Neatness counts. It carries through the whole process. It starts with the preparation of the pot. Make sure the screens are fastened neatly into a clean pot. My screen clips are always oriented perpendicular to the front of the pot to offer the lowest profile, so no one sees them hanging down in a show. The tie down wires likewise, running front to back instead of side to side, which uses less wire and is usually hidden by the pot’s feet. I have to do all of this anyway, so it really is not any more time to make it tidy. Why would you tie a crooked tie, or leave your shoes half tied?  

On a finishing note, make sure that you do not mound the soil too much. This is a consistent trait with beginners. Level off the soil where the roots start and taper it down to where you have a good ¼ inch lip around the edge of the pot. This not only looks good, but makes it so that the water stays in the pot when you water.

Happy repotting.  Scott Elser

Utah Jazz, Part 3. Zion

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This month we wind up our trip to southern Utah with a stop at Zion National Park. Before we left on our trip in October, I talked to a friend who spends the winter months in this part of the world hiking and such, and based on that, I prioritized spending more time in Bryce Canyon and less at Zion. I got it dead wrong. Now not to take anything away from Bryce, but it’s more of a cute fairy land in contrast to the jaw dropping scale and beauty of Zion. Now I know WHY they named it Zion. Of course, that came from the early Mormon settlers, but they got it right. 

We entered Zion from high elevation in the northeast corner, coming from Bryce and Kodachrome. From the moment we entered the park, we began to enjoy a landscape unlike anything we had ever seen. Soaring, huge, beautiful slabs of sandstone in a myriad of formations and colors. Trees dotting these slopes like pepper on your mashed potatoes. And more Utah red rock and Utah blue skies. 

The road wound around through a maze of mountains and cliffs. We stopped for a photo op of Desert Bighorn Sheep. Then stop. What’s this, a line? This must finally be the famous tunnel. We take a quick break and then see cars coming from the opposite direction. Time to jump back into the car and we start rolling. The tunnel was built back in the twenties, so there is only room for one-way traffic with our modern trailers and motorhomes. We pass the guard and enter the tunnel and click clack along. The road starts to curve and wind. Down we go, dotted with the occasional window in the rock. It goes for 1.1 miles but seems longer.  

Nothing I say can prepare you for what comes next. The road simply opens out at the base of a thousand-foot cliff, with a view of the entire Zion valley that sucks the breath right out of you. Partly because you are immediately plunged into steep switchbacks to descend another 500 feet to the valley floor. I am including some photos, but nothing I have done can capture the 360-degree experience. 

Since we went in October, I can’t imagine what the summer must be like, with heat and many times the number of travelers. Actually, I can, since I barely got reservations a month ahead to stay in the lovely little town of Springdale. We are not really campers these days, so the town was perfect, with many places to stay and eat, along with galleries and craft emporiums around every corner. We really wanted more time to explore there. The town butts right up to the entrance of the park and each has their own shuttle system. Both are free. You stay at a motel, which are generally more expensive the closer you get to the park, then just take a shuttle back and forth as there is really only one road in town. We hop off at the end of the shuttle line in town, walk across the parking lot, entering the park again, and jump on the park shuttle to sightseeing and the lodge. 

You are unable to drive into the main Zion valley in your car at any time except the winter. If you have been to very many parks, you are probably used to this by now and it makes things easy and enjoyable.We made a quick afternoon/evening run into the valley and did a little hiking. Like any stream laden valleys, it is lined with all sorts of deciduous trees in a flat plain. We hiked up the famous Zion Narrows but stopped where the trail ends and wading begins. That hike we are saving for the next trip when we bring our boots and waders and have more time.

The Watchman at sunset, viewed from in town

Majesty – The grandeur and majesty of Zion. This is what it looks like everywhere you turn.

Angles – The sandstone in Zion often looks like God just smashed a bunch of rocks together.

Zion Slope – Trees emerge straight out of the sandstone slopes.

Desert Bighorn – A group of Desert Bighorn sheep.

Zion Pinyon 1 – Pinyon Pine emerging from the sandstone.

Zion Pinyon 2 – Perfect bonsai inspiration in a Pinyon.

Live Oak – Foliage of a small Live Oak, unknown variety.

Cacti – it’s that dry

Viewpoint Trail – The Overlook Trail. The trail follows the base of the red rocks. The catwalk can be seen at the middle left of the photo where it swings out, then under the rocks.

Zion Tunnel – The Zion Tunnel as seen from the Overlook. You can see the zigzag switchbacks in the road and where it enters the mountain at the base of the cliff on the left.

Overlook View – The view from the Overlook. The view is much wider than this. It has been compressed with a wide angle lens to get it all in

The next morning, we were able to head out early and drive back up on top where we had entered the park the previous day. Doing our research, our first destination was the Overlook Trail. Sounds promising, eh? The trail starts right where the tunnel begins. Be prepared. This is the most enjoyable short hike I have ever been on. Now to frame that, I love trees, I love the outdoors, I love exploring new vistas and scenery. 

The trail is not hard and we made it out and back in an hour, with a twenty-minute layover to boot. The trail winds around a steep canyon, including a catwalk out over the canyon that swing back under an overhang. Around every turn there was an interesting tree (both deciduous and conifers) or interesting rock to scramble across, or a great view into the jagged canyon. The trail then gently climbs over a saddle to reveal the entire Zion valley as a reward. You see where the tunnel emerges from the cliff and realize how big that mountain really is. You can almost see both ends of the tunnel at once. The top is also broad enough to invite more exploring of trees, rocks, and scenery and open enough that no path is needed. Seeing the trees growing in these environments is simply marvelous and bonsai inspiring. I hope you get to make the journey soon.  

Repotting 

And just so that we can ease our way back into actual, applicable bonsai, here are a few thoughts on repotting. First of all, once you get all of that work done to get the tree safely into a bonsai pot, take care of it. Do not let it freeze. The act of repotting has taken away much of its winter hardiness, so they must be protected. 

Secondly, give a very good watering after repotting, until the mucks washes away and water runs clear. Then don’t water until it needs it. That might be a week or more in our weather. The tree’s uptake system has just been pruned back, so it is not able to absorb as much moisture. It is sort of like cutting the sponge in half. It will only take half as much now. As the tree reestablished itself, it will tell you it needs more by drying out a little. The last thing we want to do is drown the roots and start a cycle of decay that is hard to break. Give it just what it needs.  That means no fertilizer for a month either. Not only are you wasting it, and your time, the tree can possibly suffer. So, hold off for a bit. I always try to keep my trees out of the rain by putting them under the eaves for a week or two after repotting to make sure they don’t get too wet and this is a great jump start for the new tree/pot/soil system. If you are able to provide bottom heat, that would be even better.  

Scott Elser

Three's a Crowd

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We are all in the midst of the repotting season and it seems to take quite a toll on our personal and social time as we descend into a furious frenzy of cutting, sifting, chop-sticking, and mossing.  However, it also happens to be the best time of year to work on many trees that haven’t been repotted. Such is the case for many of our conifers that are just starting to wake up. It is sort of a lull between deciduous and conifers for me. The weather has really wreaked havoc in the system, both my schedule and that of the trees. We are all a bit confused. Things seem to be settling down and on their way to a splendid spring.

The push right now is to get my conifers pruned, if they were not last fall, so that all of the energy can be maximized and focused in the areas desired. This process also balances out the strength of the tree. One tree that I worked on recently is a largish Engelmann Spruce. Many of you are familiar with this tree. It has been seen at our shows once or twice as well as being shown at the Artisan’s Cup in 2015, National Show in New York in 2016, and the Natives Exhibit at the Pacific Bonsai Museum in 2017. Yep, that tree. It sure has been well travelled. It is also the tree that I, or we, styled together about a dozen years ago, when Boon got me into a Golden State workshop with none other Masahiko Kimura, and his young Jedi apprentice, Ryan Neil (Note the essential shell necklace –vintage Neil). What a fortuitous meeting, with my two teachers and Mr. Kimura. But since this tree spent most of last year up in Federal Way at the Natives exhibit, it was time to take stock and prune out any dead tips, cut back where I could and generally reacquaint myself with the tree.

Tree as collected by Randy Knight, 2004

 Golden State workshop with Mr. Kimura and Ryan Neil, 2006

Repotted and ready to go for the workshop

Mr. Kimura, Ryan, Myself, Boon.

 Final Result

When I exhibited the tree at the Artisan’s Cup, it was a last-minute replacement for a tree that dropped out at the last minute from California. As such, it was some really late nights getting it ready for the show. It was already somewhat wired and cutting in. So I reworked the tree and told myself that most of the wire could stay, though I cut out much of the heavier wire for aesthetic reasons and everything held pretty well. But then it was on to New York the next year, with a partial de-wiring, and adding back some detail wire. I worked on it a whole day with Ryan to get the first branch just right as a model to follow and learned much. I finished the tree myself, but I was dissatisfied with the results. There was this sort of gnawing discomfort that it just wasn’t giving the impression that I wanted. However, I was still very proud of the achievement because it was very full and much more developed than most collected spruces. Maybe too much so. The crown was almost a solid helmet of foliage with not quite enough separation between elements. It has fabulous dead wood, but the foliage was rather boring. Still wondering what the future of the tree was, I sent it to New York and back, and then to Pacific for the 2017 season.

Artisan’s Cup 2015

2016

Fast forward to our current pruning session. As I began looking for back buds to prune back too, I realized there weren’t many. Much fewer than I expected. I think this was partly due to the reduced amount of light at the Museum and less fertilizer during the season (per my instruction, at the time). But as I began to look at the branches, I think there was another big contributing factor. And that is, overcrowding. There were just too many branches to support. The tree grows like a juggernaut, but all of that energy was being dissipated into more and more branches. This is a very good problem to have. It took a good dozen years to get here, but now I realize that it was time to reassess and start thinning things out. While pruning this tree I was very committed to the rule of two. Only allow two branches at any intersection. It could be the trunk and a branch, two larger or two smaller branches, or a large and small combination. But two is going to be it and I was going to be ruthless about it. It was then that I discovered that I had junctures of three and four branches all over the tree. In my desire to maximize the foliage mass for consecutive shows I had inadvertently sacrificed the structural quality of the tree. I was so focused on the creation of nice foliage pads that I didn’t fully reexamine the tree each time I touched it. It is very common to leave three shoots on the end of branch for fullness before a show. But since I had stacked all these shows up in a row, after four years, those shoots turned into ramified branches, which I hadn’t questioned. I also discovered that this was a major factor contributing to wire cutting in at an astronomical rate. Spruce are known for wire marking rapidly and this tree is no exception. The stronger the bend, the more it cuts in. That is very predictable on spruce.

When folks are new to bonsai, they generally fall into two camps. Pruners and Waterers. The Pruners are people who will readily prune their trees down to a stump without blinking an eye. The can leave the tree rather weak and unresponsive until it builds it’s strength back up. Waterers are content to nurture their trees slowly over time. They would prefer to go through a long prayer ritual to the bonsai gods before they are ready to cut off a single shoot. I definitely fell into the former camp and have learned to balance my approach. But this spruce had had enough of nurturing. Now was the time to prune. It was DAMN hard. I spent a lot of time growing those branches. And mostly, they were good branches. I had to weigh many factors. I was not going to keep three, sometimes four, branches at one juncture. So, what to do? Do I keep the two shorter ones? Do I keep a long and short? Do I keep the one on the right or left? So, here is my little hierarchy to make those decisions.

One, keep the branches with live buds. This is so hilariously obvious yet is the one I get caught on all the time. If you have elongating species, like the spruce, and you pinched it the previous season, you won’t necessarily have buds on the tips. Plus, there can be insect damage, overall weakness, etc.… So always check to see if there is a bud. Next, do I need the length? Sometimes I do. At other times, I want to compact and keep it short. In that case, I like to keep a long and short branch. It looks more natural and develops more elegantly. Thirdly, where are the adjacent branches growing? By pruning, will I make a hole, which may actually be desirable for some negative space, or is there a better branch available to take its place? In all cases for this spruce, there was always something available nearby. And finally, can I improve the structure of the tree? Can I eliminate flaws like crossing branches? For a show, I may wire things into position to fill a hole that I would never keep long term, or so I thought, four years ago.

Freshly pruned but unstyled, 2018

Now that the job is done, I have a renewed fondness for the tree and vision for the future. It was quite harrowing at first, but now I see a tree once again. Good trees are intimidating, old and large even more so. By pruning, it got older and more tree like, and I now feel as though I can bring it to fulfill the potential it has had all along. The tree looks great and I would have to show you the garbage can full of branches to prove that I pruned anything. Please note how the apex is slowly being moved to the right and that the back branch is finally peeking around the right side. I left all of the wire that was not cutting into branches on the tree to help hold it for this next growing season, but come fall, I am really looking forward to completely de-wiring the tree and restyling it from scratch. I just did not have time now, with preparations under way for our spring show. It is now set up to grow vigorously through this next year and build up strength for a good styling session. There will likely be much more pruning at that time. But at least for now, the strength is balanced and many structural flaws are eliminated. Remember, three’s a crowd.

Scott Elser

Air Layering Tips

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It is a little surprising to me, but one of the more frequent questions I get asked about is air layering – the process of re-growing roots on a tree, either to create a bonsai from a landscape tree, reposition existing roots and planting angle, or making a more attractive radial root base. I have successfully performed the procedure on many trees including Japanese Maples and Crabapples. Sometimes I keep both the top and bottom after separation, but my primary goal is always the top, it seems. 

All of the trees I have air-layered have been existing bonsai, and were always in a pot already. I haven’t actually performed the procedure in a landscape tree. These are essential tips to make you successful. For a more complete explanation of the process, consult another resource such as the excellent magazine articles and many bonsai books in the library, or even online. 

The first thing we have to understand is what is going on inside the tree itself. Water is transported up to the leaves through the center core of the tree – the xylem, and nutrients flow down to the roots via a thin layer on the outside of the tree just under the bark - the phloem. With air layering, we are interrupting the flow of nutrients from the leaves down to the roots. With no place for the nutrients to go and with the optimal environment provided, the tree begins to send out new roots to feed itself. Since we leave the xylem intact, the tree has plenty of moisture to maintain itself. 

Taking this information into account, the best time to begin an air layer is when the leaves have hardened off and are pumping nutrients downward. This tends to be about May. With many species, we would then be able to separate the tree later in the fall. Some species like conifers may take more than one season to root. Some trees will not root at all, so do your research.

Here then, are the tips. Be sure to remove a bark ring with a width at least the diameter of the trunk. Also critical is making the cut at the new potting angle you wish the tree to be at. The new roots will grow right on this upper cut line. After the cut, an option is to wrap a wire snug up against the top cut line. Wrap this wire around twice and tighten well so that you can completely cut off the sap flow. I like aluminum because it’s thicker. I had a beech jump the cut and wire both, and then re-fuse together. So make sure you get it cleaned out adequately.

I use rooting hormone in a powder form. But it doesn’t stay so well. The solution is to make a paste by adding a little water and then spread it on the wound. It only needs to go on the upper cut line.

The next hint is a biggie. I slice a plastic pot down one side and then cut a hole the diameter of the trunk in the bottom so that I can fit this new pot around the air layer area. I make plans to either wire the pot back together once on the tree, or duct tape it together. I recommend wire all the way around the pot as the easiest method with little risk of failure.

Now that my pot is ready, I apply the hormone to the wound. Then I wrap a layer of sphagnum moss around the wound and tie it on tightly with raffia. This keeps constant moisture on the cut site and the extra pressure seems to help. Once this is done, I mount my pot in the proper position, usually with wire hanging from branches, and sometimes propped up with chopsticks. It must be immobile. The remainder of the pot is then filled with regular potting soil. This setup means that I can separate the tree at the appropriate time and not repot it for another year, allowing the new roots to grow undisturbed. This contraption may look really odd for a year, but it works great.

When I go to repot in the future, I use a piece of plywood and screw it into the base of the new air layer. This stabilizes the tree and gives me something to wire the tree into the new pot, and is invaluable in protecting the fragile new roots. If you don’t have a quite enough roots filling the pot at separation time, you might even do this outside, under the plastic pot. And then, when the roots have grown two seasons, I can safely pick out the sphagnum moss and introduce regular bonsai soil. 

Repotting

And now, here are just a few quick tips on repotting in general. There are several posts from previous year’s Branch Tips that you can review on our website that have more detailed information. There is also a summarized step-by-step procedure under Documents and Articles in the Member Services section. 

The most important thing that I wanted to mention is all of the rain that we have received. Once we take the tree out and prune off the small feeder roots, they have a diminished capacity to uptake water. That means that the tree can literally drown in all this nasty Portland wetness. We want to provide an evenly moist environment for the tree to recover and begin growing new roots. To do this, I try and keep my trees under cover for several weeks after repotting and water them only when dry – which right now with foliage barely emerging means only once a week or so.

If you are new to bonsai, beg, grovel, or become an indentured servant and repot with a more experienced member. There is no way to adequately explain what roots to cut, or how much on this tree and how much on that tree. Or, how do I fasten the tree into the pot? Repotting must be learned by doing it over and over. So volunteer your set of hands for a Saturday morning and see how fast you learn. 

Scott Elser