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I have been busy re-potting in the last few weeks and finally managed to get around to doing a project tree that I have been growing for a couple of years. When I first acquired the tree I placed 6 or so root grafts onto the trunk. 3 took and 3 failed. Since then I have been meaning to replace the failed grafts but for what ever reason, every time I have had this tree out of its pot I havent been able to do the grafts.

The arbortech and the faulty nebari in the back ground. You can see the two verticle scars from last attempt.

The Arbortech and the faulty nebari in the back ground. You can see the two vertical scars from last attempt.

The first failures were all down to the fact that the channels that accepted the new shoots were too shallow. As the approach grafted seedlings thickened, they simple pushed away from the trunk instead of fusing. I originally cut the channels with a knife and was only able to cut so deep.

This years remedy was the Arbortech! I do very little machine carving but this tool does get a bit of work this time of year as it is excellent for cutting graft channels.

The four new grafts.

The four new grafts.

The process is dead simple. It is much the same as any other approach graft except instead of using a branch from the same tree you use seedlings as your grafting material.

The basic idea is that you cut a vertical channel in the trunk where you would like some new roots. You then insert a seedling into the channel and adjust it until the seedling’s roots are at the same level as the existing nebari. Then you fix the seedling into the channel (I used big map pins), seal it all up with cut paste and let it grow. Soon enough the seedling will thicken and fuse with the trunk. Cut off the top of the newly grafted seedling and you have new roots where there were previously none. For a better breakdown of the general theory see these two posts. Post 1, Post 2.

This year, the seedlings look a little strange as they are all from the batch of seedlings I bent the year before. Having said that, the bendy little trunks were very useful as I was able to use the first bend to create a good angle for the new roots to leave the trunk from.

The bendy seedlings are care of a project i started last year.

The bendy seedlings are care of a project I started last year.

The new grafts were generously coated in cut paste and then the whole lot was potted back into its training pot.

I imagine that by the end of this rapidly approaching summer the grafts should have taken and I will be able to shorten them back before then some time the following year cutting them flush with the trunk.

Hopefully I remember to take a few pictures along the way.

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I have been trying to keep my collection from growing any larger with mixed success over the last few months. What makes it especially hard is when you help friends dig stock out of their growing rows at their nursery.

This years visit to Shibui Bonsai was much like last years in that a lot of nice stock was dug (which I am sure a lot will be featured in the coming seasons catalogue). Although a lot caught my eye, I was well-behaved and none of the ground grown stock came home. That is not to say I didn’t bring anything back to the benches…….

For a while now I have been meaning to grow some small twisted mini’s to use as accents in 3 point displays. On the benches at Shibui, Neil had a range of interesting little chinese elm root cuttings that I thought would be perfect for the project so I brought one home.

The cutting out of its original pot

The cutting out of its original pot

Today I wired the cutting to enhance some existing curves and then re-potted into a much smaller container in which I plan to start to grow a small crown from.

Often working out how to secure a small tree into a small pot which only has one drainage hole can be difficult but I have found the method shown below works well.

tie-in wire seccured to a larger wire.

tie-in wire secured to a larger wire.

Mesh installed and tie in wires ready to accept the tree.

Mesh installed and tie in wires ready to accept the tree.

The pot itself is by no means a museum piece but it is a well made Marufuji production pot. Being a little on the large side will serve it well to help the tree establish some new ramification. Once I am happy with how the ramification is progressing I will look for a more suitable pot anywhere up to half the size of the current container.

The roots were reduced accordingly.

The roots were reduced accordingly.

For such a small cutting the tree had grown a number of large roots all of which I removed and or shortened to fit into its new home.

Potted up but before i trimmed the tie in wires.

Potted up but before I trimmed the tie in wires.

After half an hours work the tree had found its new planting angle and its new pot. It is by no means a masterpiece but I think once I can develop some ramification it could make an interesting companion to a larger tree.

I think this little tree will make a nice addition to the collection in the coming years and being so small it shouldnt effect the space I have too much. In fact I probably have a whole lot of room for trees of this size.

I have had a number of old deciduous trees go through my collection over the years. Often they arrive in various states of neglect or dis-repair due to ageing owners, lack of interest or lack of knowledge. What has been interesting is the results of this lack of technique and or application.

I think most people are aware of what they should be doing. Most beginner books say something along the lines of “cut all downward growing roots off to form a flat root-base”. In essence that is correct. But why?

  • Is it to get the roots to fit in shallow containers? Partly yes.
  • Is it to encourage a flaring nebari? Partly yes.

There is one more reason that is rarely discussed or talked about when talking about root work.

What we want roots to do in a bonsai container is counter intuitive to the plant we are growing. We want a shallow root system close to the soil surface. This area of the soil profile is horticulturally the worst place in the pot to grow roots, and here in lies the problem.

The top few centimetres of soil are those most likely to experience temperature changes and drying out, both of which are no good for roots. Yet this is the area of soil we need them to occupy to form a good shallow root-base.

Correctly pruned root base

Correctly pruned root base

The above image is a vertical slice through the center of a well-formed nebari.The hairs on either side are roots and the triangluar shape is the nebari and lower trunk.

Idealy you want roots on the outside radius of the root base so that as the tree grows the nebari slowly gets larger. These roots however are occupying a zone that is not ideal for them. In order to keep them active in this zone you must force them to stay there.

To do that you remove all downward growing roots. These roots are more protected under the trunk and head straight for the cooler more temperature and moisture stable soils lower down in the pot. If you leave them on year after year the bonsai will preference these downward growing roots which are in better horticultural locations and the roots you actually want to keep around the edge of the nebari will slowly start to die back.

Incorrectly pruned root base.

Incorrectly pruned root base result.

What you end up with is something like the above drawing (this shows a tree which had a well-developed nebari and was then incorrectly maintained). All the roots on the edge have died back and only roots underneath the trunk are growing. Now the nebari will not grow in size around the edges but instead grow underneath the trunk and slowly make the root base less and less shallow requiring deeper and deeper pots to house it.

These downward growing roots often push the trunk up and show the edges of the nebari so that it appears somewhat like a blob of melted candle wax. Not ideal. Not natural.

If left in this state for a long time the edges of the nebari can begin to develop areas of dieback that will often spread from the edge of the nebari up toward the trunk. All in all a bad result.

So if you have deciduous trees that are beginning to form nice root bases be sure to ALWAYS take off the downward growing roots. It is not just to fit the tree into the pot but it is mainly to ensure your roots grow where you need them to and this will keep your nebari developing correctly well into the future.

Re-potting this year has been a rushed affair where I have been doing it when ever I have time. Mostly this seems to be under garden lights after work. Spring seems to be a little early this year which hasn’t helped as the schedule has had to be brought forward. Having said that, I have nearly got through all my trees. I have a handful left to do that I hope to get done this coming weekend.

As i have been in a rush there hasn’t been much time (or good light) to take many pics. Most of the re-potting I have been doing has been fairly un-interesting anyway and mainly just renewing of soil and replacing the trees into the pots that they came from.

One tree I did get to do during daylight hours was a trident maple. The pics i took were with my phone to see how that would work out and as you will see they are fine in good light (see the buds pic) and not so great when the light was getting low when i had finished re-potting the tree.

Buds starting to move

I talked about this tree with Boon while he was in Melbourne and also Hirotoshi saito. They both thought that the tree should be rotated slightly to the right. I had been tossing up whether or not to do this for some time before speaking to them but their advice made me decide to go ahead and try it. I am glad I did. A small tweak such as this 15 degree turn makes a lot of difference.

Left: the tree in August 2011. Right: the same tree, August 2012.

The reason I had been debating whether or not to make this change lay in the nebari. In the 2011 picture you can see that the nebari’s spread has a somewhat flat side to it which was facing the front. When it was rotated this formed an angle which is a little strange although there are a few good results of this change. First the slight thickening about 2/3rds of the way up disappears and there is more movement in the trunk. Also the branching is better from this new front.

I also tilted the tree forward a little. this moved the root ball a little and raised the soil in the rear of the pot a bit. I will correct this next re-potting once the roots re-establish themselves in the new position. I think i will also try to move the tree a little more to the right, i shifted it a bit this year but having seen the photos i think it could move over some more.

If you are interested in more of the re-potting process you can see the pics from last year HERE.

Spring is certainly around the corner and all my trees seem to know about it. They are for the most part starting to swell their buds. As a result I have been re-potting. I re-potted one of my trident maples a couple of days ago to get it ready for the springs growth and thought I would share some pics of the process.

The bottom side of the rootball before and after the work.

Surface roots combed out.

Once the roots are all in order you can continue to pot up the tree. In this case it went back into the same pot.

Re-potted.

Another year and another re-potting…..

The tree I worked on this weekend was a corky bark elm. It’s a tree a friend grew and I purchased from him a year or so ago.

The tree as I received it.

When i bought the tree, the trunk was  covered in moss and the branch structure was difficult to see through the foliage. Once it was home, the first step was to prune the tree and clean the trunk and root base.

After a prune and clean up.

After cleaning the trunk and nebari and giving the foliage a good prune a few things became obvious. Firstly the tree had a good nebari thanks to the work my friend did while developing the stock. The trunk on the other hand was not bad but had a gentil curve in it which for some reason seemed awkward. The branch locations were ok but would require a fair amount of work to form an upright tree.

Un-potted

A season passed and I finally got around to re-potting. Re-potting was my chance to change the planting angle of the tree and really think towrads the future of the tree.

An Option?

I had toyed with the idea of making this tree a semi cascade while it was potted but once I bare-rooted the tree and tried it in a few semi-cascade positions I wasn’t entirely convinced. I spent some time tilting the tree this way and that, changing fronts, imagining grafted branches until I finally settled on a design.

Cambium layer exposed.

I pruned a few branches and also exposed some cambium in a couple of areas. The tree was to become a raft. Elms root very well but I felt a few areas of exposed cambium could only help speed rooting along the trunk up. I also put a couple bits of wire on the main branches to set the basic structure of the tree.

The final outcome.

This is a fairly one way solution. In order to get the trunk to lie over I have had to cut off half of the nebari making standing the tree up in the future not really an option. That said I am sure you would agree that this clump or turtle back style transformation is definitely one that has improved the tree for the better. The tree has a long way to go and it will be interesting to see how the corky bark copes with the close soil contact, that said I think that in the future it will grow into an interesting tree. Depending on how it leafs out, I will most probably give it a prune and full wire some time in mid summer. Hopefully by this time next year it will have rooted enough along the trunk to get it into a more shallow pot and really start its journey as a bonsai.

Right now Melbourne is deep within the throes of winter, in fact, judging by the temps we are right in the middle of it. It seems that my quince has other ideas. It has been steadily waking up and has just started producing new growth as if it is spring time.

New Growth.

As a result I have had to re-pot. This is the second re-potting I have given it since I have owned it and was pleasantly surprised by the root-mass I found after the hard treatment it received after its first re-potting.

Looking at the roots from beneath. You can see that the roots that were growing downwards have been removed leaving an almost solid wooden base..

The tree went back into the same pot is was in previously. One thing you may notice is that a lot of my trees are in green pots. There is a reason for this. Where I live most pots of this age were in green tones. Around that time there was a local grower that hated blue pots and as a result of his experience and influence this lead to very few blue pots being bought during this time. As a result all my pots (which have mostly been bought second hand from other local members) are mostly green.

The tree re-potted.

I have not yet seen flowers on this tree. Hopefully this year I will get a few. I am not sure if this tree is mature enough to flower or not, or for that matter how old a quince has to be before flowering. If anyone reading this has an idea please post in the comments.

New buds.

A lot of people have told me that the quince is an early riser and recently I was reading through some old Bonsai Today magazines where in one article they suggested re-potting in autumn due to the early growth and flowering. I think I will give that a go next year.

I have begun to re-pot some of my deciduous bonsai. I like to re-pot my pines closer to spring time so I do my deciduous species a little earlier in order to leave plenty of time for the conifers.

The tree in today’s post is an English Elm (Ulmus procera). I picked it up at a local bonsai show last year. I have always liked clump style bonsai and am always on the lookout for suitable stock (which is quite hard to find). When I saw this little clump I quickly grabbed it.

The Elm after a year in my care.

Since owning it, I have fed, pruned and wired a little. It proved to be a very strong grower so I defoliated 3 times during the growing season. After the 3rd time it did not bud out as strongly as I would have liked which means I will only do two defoliations this coming season.

As the tree had been in a rather large terracotta pot it had developed a large rootball, as a result a fair amount had to be pruned off in order to get it into a bonsai pot.

The underside of the rootball showing the cuts where some lager roots were removed.

This re-potting I concentrated on removing all downward growing roots. This lead to a large percentage of the rootball being removed. Although Elms are strong trees I thought that I would not prune the surface roots as much as I might otherwise due to the large amount I had already removed from the rootball.

The surface roots.

As you can see from the above image there are a number of large un-tapered roots. In the next re-potting I will be looking to reduce these roots to introduce some taper and delicacy to the rootbase. For the time being though, these roots will help the tree recover from the loss of the larger part of its previous rootmass.

If you read my post “Two pots” you will be familiar with the two pot options I had for this tree.

The two pots I had to choose from.

Although I like both choices I ended up chosing the left hand pot.  What i found interesting was how each pot gave the tree a different feeling. The left pot ( ) gave the tree a more spreading feeling while I felt that the right pot ( ) made the clump appear much taller. The beauty of liking both the pot/tree combinations is that I will happily alternate which pot I use in future re-pottings to give the clump a new feel each year.

The prepared pot (minus tie-in wires)

For its size the Yamafusa pot had a good number of drainage holes, each of which needed mesh screening to prevent the soil media falling out and to prevent some of the larger pests getting in.

The potted Elm.

The Elm was then tied in firmly and soil worked in around the rootball. I feel the pot is a good fit to the clump and the green of the pot should work very well with the yellow autumn colours I hope to get next year. This clump has a long way to go before it is a good bonsai but it is now firmly on its way. Hopefully heavy feeding combined with defoliation will add a fair amount of twiggyness and branching to the tree to further enhance its image.

The tree below is one I worked on a couple of years ago. It is a large Shimpaku Juniper that had some great deadwood. When I was working on it, it was in the process of having some new roots grafted onto it. Because of this the styling was kept to just main branches, leaving the tips somewhat free so as not to stress the tree too much.

The tree before any work May 2009. There is a foam box that is holding soil for the grafts at the base. The layer was on the tree so that the deadwood would be brought closer to the soil surface and give the tree a more solid base.

After several hours wiring.

On my latest trip to Japan I re-visited Taisho-en and was reaquainted with this tree. The grafts had been a success and the tree had found a new home in a new bonsai pot.

It’s always nice to see trees you have worked on after some time apart. I get a similar feeling to that of  seeing an old friend. When I saw this tree in the nursery I took my time looking over it and revisiting the familiar curves and lines of the trunk and branches.

The tree as of January 2011. The angle of the tree is a little more upright now and the base appears much more solid now it is lower in the pot. If you look closely you can see a tuft of foliage at the base that is still attached to the root graft.

I wonder if we will cross paths again.

The tree in this post was another i worked on while in Japan. It arrived at the nursery one day and was in need of a re-think and re-style.

The major change was to stand it up.

 

Juniper Before

Before the work.

 

I first wired the tree, keeping the small second trunk and then re-potted it into its new upright position.

 

Juniper After

After the work

 

As the tree had its angle changed so dramatically it needed time to re-establish a new rootball that could support it in its new position. In the mean time a bamboo prop was used to take the weight of the tree while the rootball became stable enough to support itself.

Unfortunately some of the lower shari had been buried in the previous potting angle and as a result had rotted. I feel that the base would have appeared much more impressive had it still had deadwood at its base.

It was a nice tree to work on, but at the time i guess it got lost amongst all the other high quality trees in the nursery.

This was by no means a top tree but looking back at it now I would kill to work on material such as this in Australia.

I guess I will have to sharpen the shovel and keep an eye open for urban junipers in friends gardens.

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