REPOTTING A JAPANESE MAPLE

Japanese maples should be repotted every two or three years. Immature trees should be repotted more often than mature ones.

The following series of photographs chronicles a repotting demonstration at the March 2001 monthly meeting of the Toronto Bonsai Society. The tree belongs to John Biel.

*text corresponds to the image below*

The tie-in wires are cut so that the tree can be taken out of the pot.

The root ball is being raked out. It is important to move the rake outward from and perpendicularly to the trunk. In that way, crossing roots are eliminated and only those radiating outward from the trunk are kept. Eventually, that practice will lead to roots that can justifiably be called nebari.

I like using this type of rake (either two- or three-pronged), because the thickened end allows the rake to be used with a minimum of hand
pressure.

The underside will be a dense mass of roots (not shown), which must be eliminated. The remainder of the bottom of the root ball has to be combed out as well. Loose roots all around the root ball are then pruned back.

The underside of the pot, showing how the screens were fastened.

The pot (it is the same pot as was used previously) with tie-in wires installed and a bottom layer of soil.

The tree is placed in the pot. This picture gives some indication of the extent to which the root ball was reduced.

The tie wires are fastened by using a pair of pliers, pulling up on the wires and twisting them at the same time. Care has to be taken that the wire does not break in this process.

With the tying in completed, a stub of the twisted wires is visible (faintly) between the front of the trunk and the rim of the pot. The stub should be twisted to one side so as to make sure it hidden from view once the pot is filled with new soil.

The new soil is being worked into the combed out root system with the help of a chopstick. Lightly tapping the rim of the pot with fist or mallet will further help to settle the soil.

The tree is placed in water up to the rim of the pot until the top of the soil is moist, indicating that the whole root ball is thoroughly wet. Excess water should then be allowed to drain out.

The repotted maple about ten weeks later at the Spring Show of the Toronto Bonsai Society.