Repotting a Japanese maple

Back in winter I took a few photographs of an air-layered Japanese maple getting repotted during a Bay Island Bonsai workshop.

Combing out the roots – Japanse maple ‘sango kaku’

The new roots are well established. The next step is to get them to fuse while improving the ramification. Jeff, the tree’s owner, kicked off this phase by bare-rooting the tree and repotting it into a large, shallow, growing container.

After combing out the roots and cutting them back, Jeff washed all of the old soil out of the rootball. Clearing away the old soil is an important step in getting the roots to fuse. Small soil particles can slow down this process by reducing the drainage and impeding contact between roots. Here’s the tree after completing the root-work.

Root-work completed

Jeff happens to be quite crafty when it comes to making bonsai containers. He created the pot below specifically for developing the tree’s roots. The light colored soil is pumice, used for drainage. The speckled soil in the center is the actual bonsai mix consisting primarily of akadama, pumice, and lava.

Ready for the tree

The pot looks huge for this tree – and it is. But by using a large pot, Jeff can let the tree grow uninterrupted for more than a year before having to repot again. This will allow the roots to develop more quickly than they could if the tree were repotted every year for the next few years.

Ready to tie the tree to the pot.

After nestling the tree into the mound of bonsai soil, the next step is securing the tree with bonsai wire. See “Repotting a trident maple – securing the tree in the pot” for details about this process.

Tree secured

Michael Hagedorn provides a good fertilizing tip designed to encourage maples to develop superb nebari. If Jeff continues the good work for another 30 years, he may end up with something outstanding like the tree below – or maybe something better!

Japanese maple from Ebihara’s garden