I love this Shimpaku on Rock as is, but it's rootbound.

[SeeSeas]

I picked up this beautiful Shimpaku on Rock early this summer. I have little history on it other than it being purchased at the 2020 Mammoth Auction. It is a surprisingly heavy son-of-a-gun. There was no new growth this summer. Over the summer the circling roots started popping out of the rim of the pot. In the past week or so it stopped draining quickly and water started to be slower to absorb. I have no idea how old it is or how long it has been in its pot.

I'd like to keep it in this pot because I enjoy the proportions and it is beautiful too. Can it be done and does anyone have tips on approaching it? I do hope it can wait until Spring. Perhaps some skewering or chopstick intervention can hold us over?



How much disruption of the circling roots can it take at repotting time? Due to the weight of the rock I am trying to come up with ideas about how best to support the rock and roots during repotting too. I thought about using wide stretchy self-adhering medical bandages, just in case.

Bottom line: I am afraid to touch it. I am afraid of not touching it.
Bonus round: If anyone knows this tree, I'd love to hear about it.

 

[WNC Bonsai]

Go to Bonsify on YouTube. He did a great video earlier this year on repotting his root-on slab juniper.

 

[SeeSeas]

I watched that video twice since I have a larch on slab too. Sorry about the failed photo upload the first time around!

 

[Shibui]

How much disruption of the circling roots can it take at repotting time

At repotting I take around 1/2 of the roots of juniper. Sometimes even more so no need to be frightened of repotting this one. Reduce long, thicker roots substantially and finer roots enough to fit easily back into the pot.
My approach would be to remove the tree from the pot. Cut through roots and soil right round the rock about half way between rock and edge of the root ball.
Next cut a thin slice of the tangled roots off the base.
Now rake out some soil from the remaining roots.
Final trim to remove any long and thick roots uncovered by raking.

Place mesh over drain holes. Spread a thin layer of bonsai soil in the pot to bring the planting back up to required level then place the tree back in. Top up with more soil round the edges.
The rock may or may not require tying into the pot. Some have a good flat base and will sit well. Ties are only needed until roots grow into the new soil so probably around 3-4 months for juniper. Use whatever is needed to get it secured regardless of how it looks because ties are only temporary but important to hold the tree steady while new roots grow.

Hoping the rock has not been glued to the pot as is sometimes the case.

 

[penumbra]

My advice based upon your reluctance "I am afraid to touch it.", pay somebody who knows what they are doing and has a good track record to either do the re-pot for you or to walk you through the procedure. Based upon what you have said, nothing else makes sense.
Good luck.

 

[johng]

Trees don't get root bound all of the sudden. It is in a shallow tray so it is not unusual to see roots on the surface. Your composition is not technically a rock planting...it is a root over rock planting. Junipers love to be root bound and perform best with an abundance of roots. I would continue to care for this tree as you have...careful watering is always called for with rock and root over rock plantings.