I have a 25G JM in a larger container. When I removed it from its pot, the potting medium on the outside seemed fresh/fresh'ish . The tips were at the wall but not circling. The roots have not outgrown its current existing pot. However, I expect the overall plant nt itself has just been repotted its whole entire life....with old expired potting medium from the very core to at least a 10G rootball size Planning to give it a full on bare root wash and clean up any circulars roots I spy. There are some surface circulars I see but that is to expected when dealing with a larger potted plant that's been up-potted it's entire life. It's Late Winter.....getting that spring fever. My hose bib has a anti-freeze bib so I will have water coming out the hose. Ha, I've been using it all season as such washing the cars when the weather allows How -early- is too early to repot: root wash a JM. Am I Bette aiming to do this -full dormancy- or just when it's about to -wake up-.
Maybe someone with vast (and varied) experience with this will chime in, but until that time I'll offer my anecdotal experiences: I have many JMs in pots and over the past two decades have re-potted them any time over the winter that is convenient for me, and have never noticed any difference in how they do early vs late dormancy. Secondly, I have a single anecdotal experience with a large Tamukeyama that had been in the ground for years, that I donated to a friend. It just happened to be that mid-January was the most convenient time for the two of us to get together to undertake the project, even though I was concerned that we should wait until much later in dormancy to do it. Digging it up required cutting many roots, some of them large, and to break away a lot of soil from the remaining roots in order to be able to handle the weight of the tree and load it in his truck. Three years later (and even in its first year after re-planting), the tree is thriving spectacularly.
You could always check out this video for step by step and play by play details As long as the soil is not frozen and it is in its dormant state, away you go
Of course I jinxed it and the mild winter - has snowed on and off for the since this posting. I've bare rooted *shrubs* of all sizes all the time.....I did kill one expensive conifer doing a bare root. I dunno if I just had a bad plant from the nursery to begin with or was it due to my bare root wash.... So I'm just slightly cautious about bare root washing $$$ plants but I suppose on another 2 weeks or so, when hopefully the snow is gone, out comes the hose for a bare root wash. I am going to try something different though this year. I've never done it but I'm going to this year. Instead of using water, I'm going to use the air from my compressor to bare root this thing
Bonsai enthusiasts advise to leave a little of the old soil to ensure there are enough mycorrhyzae. Air-compressor : aren't you afraid some of the roots would dry up ? Though some people completely wash the old soil, I don't : I always leave some of the old soil if the tree is healthy because there is some microfauna that is useful for the soil to be healthy. Of course there is some too in a new mix, but as a friend says, it's "belt and braces" (ceinture et bretelles).
Is there *myco* in a soil-less medium - does it survive in a potting if the soil is not disturbed or watered by tap water which has chlorine, or serving after a growing season where there is winter temps ? If there is, presumably and I may be incorrect in this, but if there was, does it DIE off in the winter temps ? I was under the idea it does die off , even when adding it in, after a winter season I do add myco if I'm repotting while the plant is ~active~. Mainly as my understanding is that myco needs to be in direct contact with the roots in order to survive/sustain. I know there are different things you see being done, myco water drench, myco and mix the potting soil. What I generally do when adding myco, is right before I put it into the pot, I sprikle some on my domed planting also. I also spray the rootball with a mister, and the put the myco in direct contact with the roots *the misted water helps to keep the myco in place*
Just one practical point from me associated with using mycorrhyzae fungi powder…if you water the plant thoroughly after planting (following normal good practice) logic tells me you will inadvertently wash more than half of the myco away within minutes of planting, expensive and rather inefficient! I have started watering the mound of planting substrate before adding the rootball, then add the myco direct to a damp rootball all around and then add pre wetted substrate to fill the hole or pot..pots in my case. Am interested in all your thoughts on the above..
If I am tinkering, it'usually about 2 weeks from today or a month from today...where the roots are somewhat actively waking up and I am tinkering with doing some sort of root pruning. It's my understanding, that the MYCO needs to be in direct contact with the roots in order to survive. Granted variables like if you water it from the tap *which has chlorine in my tap*, that will kill the Myco, that may just un-do whatever one had done. I approach it mainly as *best effort* if I'm going to some sort of root management. Especially for pots since it is a -lifeless medium-. IME, the Myco does wonders...but the environment IME, is critical. Generally the spring rains is sufficient enough for the period in which I've added it that it doesn't need supplemental watering.
I missed the air compressor remark I dunno. Root washing involveds alot of water...then alot of old wet potting medium Here I was thinking, air compressor....easily use the blower to blow all the organic matter into the closest dirt, lawn, etc It's winter. It's dormant. I do plan to mist the roots heavy once I have done the root wash as I begin teasing out the roots, and Identifying the circulars, semi circulars and all that for tree that has spent it's entire 25G life in a pot. It was not root bound when I put it in a larger pot last year, but the roots were teasing on all the sides. I never considered the roots to dry up.....if after post blow out, it would be misted . Bad idea ?
I dunno... But as I already said, unless the tree is sick, I don't totally wash off the old soil. Look at Otto's video : he doesn't, and he is a very savvy maple grower...
I may be looking at this wrong. I'm not a long term pot grower but I do grow them in pots to test siting and or grow *shrubs like plants* to get them to a certain size before I plant them......I use airpots to max out root growth. If I'm going to the trouble of root pruning:management, isn't it *best effort* just to refresh the media from the core if one has the means and will to do it ? I know Myco was discussed and unless I am looking at this wrong, the winter temps killed off whatever Myco was present in this soil-less medium. I just so happened to snap this pic the other day https://www.dropbox.com/scl/fi/ixp7...ey=q5z5htlrs2lnsz1aezytd8ula&st=wg496fru&dl=0 If you can see at least on the periphery of it there is alot of roots in its mass. What we see already is a strong stream of water I did when I repotted it from it's original 25G to it's current container just to get rid of the extra excess composted bark to promote the roots to go down. In snapping this pic and looking closely, you and see how many roots are there even with just a strong blast of water washing out the top.
Replant it a bit lower in any case. Say, one inch lower ?... It's a bit early for me to repot, but I'll post photos of what I call "star-shaped root cutting" (for bonsai, but it's about the same for large potted trees)
This is going to be the 1st *large* rootball I'm going to do a prune out. I probably will just use secreters as it's a cleaner cut - Ha, but I have a 30" BowSaw I bought just in case I decided to be lazy. Didn't really need it but it was a good 'excuse to add another tool to the garage
