The three prong root takes are for scraping across the bottoms of established bonsai already in pots. They’re not particularly useful working the tops of rootballs. Only the flat bottoms.
Lessons Learned From Repotting
- Thread starter Josh88
- Start date
Josh88
Shohin
Remembered another one! When I was first learning the steps of repotting, I was told to water thoroughly until "the water runs clear from the bottom of the pot." This year I was given a good explanation of why we want to see the water running clear and it became apparent why this is so important. No matter how well we sift our soil there will inevitably be dust left on our soil particles. If we give a just-repotted tree our usual amount of water, we will likely wash that dust off of the soil particles, but not necessarily out of the pot. If we do this the dust will settle and clump at the drainage screens and we will immediately loose the good drainage we just worked so hard to provide. I'm a fan of understanding why I'm taking the steps I'm taking so I don't skip something that may appear trivial at first glance, and this could very easily be one of those instances where we shortchange the last step and ruin the work we've done.
Shibui
Imperial Masterpiece
I also find the single tine root hook far more effective. Little 3 tined rakes are almost useless for any root work.
Again, you’re not using it for its intended purpose.
I’ll describe my potting process, and the tools I use on an established bonsai below. (Potting a tree from collected material, and those from nursery stock require different techniques.)
The 3 toned fork is used to scrape across the bottom of the root ball on a tree that’s been living in a bonsai pot. You know how you get that mat of roots flat across the entire bottom? The 3 tines fork pulls those off. Then take scissors and cut the whole mat of tangled roots off clean. Then, take the 3 toned fork, and drag across the bottom of the root ball, evenly, from one side to the other. This pass loosens and pulls what used to be the “drainage layer” of old bonsai soil out. Then, another pass with the scissors will trim the downward roots that grew into to “drainage layer”.
At this point, you should have a smooth, flat rootball. The above steps are the first part of the rootball that prepared when repotting. Now that it’s flat, the tree will sit stable while you work the top and sides of the root ball.
The top and sides are worked primarily with bent tip tweezers. The tweezers are dragged across the top of the rootball starting up near the trunk, and outward away from the trunk. This removes the moss, weeds, duff, old fertilizer, etc. from the soil surface. The tweezers are dragged from the center up at the nebari outwards towards the edge of the rootball a little at a time, working my way around the rootball. During this process, I try to shape the rootball surface so that I create a gentle slope downward from the nebari to the edge. So, I take more material off near the edges. If I find crossing roots, I try to straighten them out so that they become radial if possible, if not, they get cut off. Sometimes on old trees, the bent tip tweezers may not be strong enough. I then use a slender root hook, single pronged, to dig in between roots. Masakuni makes a really good one with red handles, and it’s really very inexpensive, under $10!
The bent tip tweezers work well because the bend allows you to drag across roots with minimal damage. And if you need to poke in between two roots, closing the tines gives you the “sharper” instrument you need.
Once ive gone around the surface, I trim off the excess roots ive pulled off, and the circling roots I’ve exposed. Then, using my bent tip tweezers once again, I go around the outside of the rootball, and I pull the soil off the outside 1/2 to 3/4 inch of the roots. When I’m done, my rootball is “fuzzy”, all the way around on the edge. (Remember, it’s smooth, no fuzziness, on the bottom.)
It’s now ready to go back into the pot.
I prepare the pot (should have been prepared before root work), put on drainage layer of larger pumice (if desired) pour in a pile of soil, then place the tree on the pile of soil. I place both hands on either side of the rootball, then “scrunch” the tree down, wiggling the tree back and forth into the pile of bonsai soil until it’s reached the proper level in the pot. I tie it in securely with wire. So that the tree cannot move at all! Then, I backfill with soil. Then lightly chopstick it back in. I use just one chopstick, insert it as deep as I can, and gently wiggle it back and forth. With my finger on my other hand I push soil down into the void the chopstick has made. As I do this, I lift the chop stick a little, but continue to wiggle, all the time pushing more soil down. Then move the chopstick over an inch, and repeat. It’s a gentle jab, but mostly a lot of wiggling and backfilling. I try not to break roots, or soil. The idea is to push soil down, so the hand NOT chopsticking is doing the most important job! It’s pushing the soil down in the void! Doing it this way is pretty quick. Most people chopstick far too much. And too forcefully. They break roots, and doin it too much pulls the larger particles of soil up, and pushes the smaller particles down, which is NOT what you want!
Once the chopsticking is done, level out the soil. Then comes my favorite part! I press the tree down into the pot lightly, and tap the outside of the sides of the pot with my fist. All 4 sides. The soil will settle a good bit all around! It’s amazing! I usually have to add more soil because it’s settled so much.
Then, I use the little broom to smooth the surface, and get it evenly flat everywhere. I try not to mound the soil, and have the level of the soil about 1/4 inch below the rim. That way, when I water, the water will all go straight down. It doesn’t run off.
After, the soil is level, I tamp it down to further compact it, then water until the water runs clear. Then, the tree goes back out to where it normally lives. I mostly have conifers, so they go back out in the sun!
Josh88
Shohin
Thank you for the detailed description Adair! I have not done the tapping on the sides of the pot, although I know I have read/heard that before. Another step to add for a better job done next season!
amatbrewer
Shohin
Much appreciated! This was very informative, and I am sure I am going to read this at least a few more times.
Would you be willing to share what changes to this process you make for trees still in training (e.g. soon after collection or not long out of a nursery pot) to help get it from the 'bowl of spaghetti' stage to a well defined flat root ball? I know I for one could really use to learn some 'best practices' in that area.
BTW It seems (to me) like we spend a lot of time talking about topics like styling and soil, but far less time talking about roots and nebari then the subject deserves given how it is fairly universal that "good bonsai starts with the nebari" and roots/nebari can be the one of the hardest things to fix/develop.
Collected material can be rather complex since there are so many possible variables. Roots may need to be grafted on. The root balls may be very irregular in shape, or extremely long. It may take several iterations to reduce the rootball to pot size, and develop enough roots to support the tree in a bonsai pot.
Nursery material is usually easier. Deciduous trees can usually be bare rooted whereas conifers should not be completely bare rooted. The usual practice for conifers is to do a “half bare root” repot on the weaker side of the root system, leaving the stronger side intact. Use BoonMix. Two years later, do the other side.
BubblePopScott
Mame
Thanks Adair your posts are always so good. Thank you for your experience on a page.
rockm
Spuds Moyogi
I typically use a small saw to remove the bottom third of the root mass at repotting.
I suppose that could work. After I use the 3prong fork, I cut the downward growing roots with scissors. Makes a clean cut.
I have a pair a scissors where the handle is bent relative to the blades. Gives my fingers room to work without rubbing against the base of the rootball. The key is to get it flat, and no little roots sticking out.
Thanks! I try not to steer people wrong.
(Some people prefer not to be steered, however, and they have issues with me!)
Could you show a picture of the saw and maybe where you got it? Also do you saw off the bottom 1/3rd of the root ball on deciduous and conifers? Thanks!
Shibui
Imperial Masterpiece
Thanks for such a detailed description of your approach to root pruning. Anyone who wants to be steered is welcome to follow Adair. RockM uses a saw to cut the roots off the bottom of his bonsai. Probably achieves the same result as Adair in much less time. Anyone who thinks this approach is good can follow. I use the root shears. First cut is usually around the edge of the root ball to remove the circling tangled roots at the edge of the pot. That gives some room for fresh mix around the edges and some leeway if I decide to move the tree a little in the pot. I note that Adair uses the tweezers to 'fuzz out' the roots round the edge then it is ready to go back in the pot - no mention of trimming roots around the edges. How does that fit back in when roots were already tight in the pot before??
Next I use the root shears to cut a slice off the bottom of the root ball. I'm confident this produces the same
Repotting is the same as Adair has listed above except I don't use a chopstick or fingers to press mix in. There's really nowhere for the chopstick to push the mix to and, as he mentioned, chopstick can separate soil particles and damage roots so no point in doing this. Also I don't press the tree down into the pot (It is already securely wired down so can't really be pressed down further?) or tap the pot to settle the soil. The next step - watering, will do all that better and more gently. After watering in, if the mix has settled, I add more to bring it up to finished level and the tree goes back onto the bench where it normally lives.
So there you have it. 3 different approaches to repotting and all of us have been using them for many years and producing healthy bonsai.
Steer whichever way you feel is good for you.
RockM can tell you his approach as well.
Next I use the root shears to cut a slice off the bottom of the root ball. I'm confident this produces the same
at the same level as Adair but in a fraction of the time? and probably a similar result to Rock in around the same time?
Repotting is the same as Adair has listed above except I don't use a chopstick or fingers to press mix in. There's really nowhere for the chopstick to push the mix to and, as he mentioned, chopstick can separate soil particles and damage roots so no point in doing this. Also I don't press the tree down into the pot (It is already securely wired down so can't really be pressed down further?) or tap the pot to settle the soil. The next step - watering, will do all that better and more gently. After watering in, if the mix has settled, I add more to bring it up to finished level and the tree goes back onto the bench where it normally lives.
So there you have it. 3 different approaches to repotting and all of us have been using them for many years and producing healthy bonsai.
Steer whichever way you feel is good for you.
I shear rather than saw except when the roots are so tight the shears just won't cut through, then the saw comes out but usually take off around 1/3 of the depth and do that on both conifers and deciduous except some of the older bonsai where the rootball is more wood so I can't physically cut off 1/3 any more. With those just trim off whatever I can while still leaving some roots.
RockM can tell you his approach as well.
rockm
Spuds Moyogi
I don't have a pic of the saw at the moment. I got it at a bonsai show a while back, looks like a hand held sickle, wooden handle, eight inch serrated blade.
I don't work with conifers, but I wouldn't use it them. Deciduous trees can take more root reduction than conifers, so removing the bottom third of a conifer's root mass could be a problem.
rockm
Spuds Moyogi
My process is a lot like Adair's after the initial step of removing the bottom third of the root mass at the beginning. I have found doing that allows easier work on the remaining roots, since it can immediately free up the soil in the interior of the roots, as well as get rid of troublesome root tangles. using in on the first repotting of collected or new stock trees, however, can be an issue, since those can have large to very large main roots that far down in the root mass. I still use the saw, but when I run into a large root, I use big root cutter tools on them for initial reduction.
Josh88
Shohin
Another approach to cutting off the lower section of a root ball is using a paint scraper, as shown in a few Mirai repotting videos. I have tried this as well as a saw, and personally prefer the paint scraper, as it's very easy to create a nice flat bottom, it seems to provide a clean cut to the roots, and I don't feel like I'm dulling a tool that can't easily be re-sharpened or replaced. Lots of ways to skin a cat around here.
Wilson
Masterpiece
I have never seen a scraper used to cut through roots, do you have a link to the video? Or maybe a photo of what type of scraper you are using? I am always curious when I hear something different like this.
atlarsenal
Omono
Just a 3 or 4” stiff scraper, sharpened as sharp as you can get it. Lay the root ball on it’s side and slice through it. You still have to use root cutters on large roots but it works very well when you have a dense mat of feeder roots. You do have to sharpen your scraper about every repot though.
Josh88
Shohin
There are a few videos on Mirai Live that show this I believe. If you find the "Deciduous Second Repot" video, you will see it at the 20:45 mark. You are looking for a paint scraper, which has a sharp beveled edge, as opposed to a putty knife which has a narrow, but squared edge.
Wilson
Masterpiece
Cheers @Josh88 and @atlarsenal sounds like a nice technique for a more dense refined root system.
Similar threads
