The Japanese maple below was created by Gene Lynch. It had been a while since it was repotted so I removed it from the pot to check out the roots.
Japanese maple group planting
Jim Gremel pot
As expected, the roots formed a solid mat along the bottom of the pot.
Matted roots
My goal for the repotting was to reveal the trees’ surface roots and remove as much old soil as possible.
I started by removing the soil that had built up above the trees’ surface roots.
Buried surface roots
Using a chopstick and bent-nose tweezers made it easy to remove the top half-inch of soil that covered the surface roots.
After removing the upper layer of old soil
A nylon brush helped remove moss and stubborn soil clinging to the base of the trunks.
Brushing the base of the trunks
After removing the broken down soil and cleaning the base of the trunks, a quick rinse removed the last traces of old soil.
After rinsing off the muddy soil
Once the top of the rootball was ready to go, I repeated the process on the bottom of the rootball. Here’s the tree after this work was complete.
Root work complete
I considered bare-rooting the tree but didn’t want to stress it too much so I left some of the old soil. I’ll plan to remove the remaining old soil in a subsequent repot.
From there I returned the tree in the same pot and applied a thin layer of shredded white sphagnum moss. The soil mix is roughly 65% akadama and 35% pumice.
Repotting (and pruning) complete – 29″
I expect the tree to stay in this pot for another two-to-three years before it needs repotting again. During that time, I can start making improvements to the branches.
I can also think about whether or not to rearrange the trunks. I noticed that the rootball was flexible during repotting so it will be possible to make changes, if desired, the next time the tree is repotted.
New Podcast Episodes with Kaya Mooney and Carmen Leskoviansky
The Bonsai Wire Podcast recently featured interviews with Kaya Mooney, an apprentice at Kouka-en near Osaka, Japan, and Carmen Leskoviansky, caretaker of the bonsai collection at the Matthaei Botanical Gardens in Michigan. You can check out both episodes at bonsaiwirepodcast.com.