Andrew Edge

This repot is to try to correct the large and thick roots around the nebari. Whilst we do want size differences in the surface roots around the trunk to create more interest, roots that are too thick can dominate the others if left uncontrolled. Like branches allowed to grow untouched, roots will thicken rapidly, taking up the lions share of the energy and withholding the energy from the other roots. This will result in an uneven spread of the surface roots of the tree. By cutting back the thick roots or splitting it with a chisel, we can reduce its energy uptake, allowing the roots around it to catch up. 

Using a chisel, I split one of the roots along it length and used a small pebble to keep the sides apart (see photos below) then cut it back. Try to create an uneven split with the chisel, varying the root thicknesses. Two other thick roots, I used a bamboo piece to keep them apart (photos right) and cut them back to smaller roots. I will split these into smaller roots at the next repot. 

Another large root was reduced to smaller roots closer into the trunk (photos below). The smaller roots were either tip pruned or left alone. I defoliated the apical area of the tree, pruned some of the thicker branches then repotted the tree. It was planted slightly deeper than usual with sphagnum moss used as top dressing to protect the weaker surface roots whilst the tree re-establishes itself. 

Future work will involve more splitting of the thick roots that were only cut back this time. Improvement of the nebari will result at every repot if proper techniques and pruning is utilised effectively. I’m looking forward to my ‘sumo’ bonsai evolving into a mature bonsai.