I dont have many long term results (I only started this technique last year), but I have begun to experiment with growing on and through tile with Japanese Maple, Trident Maple, Crepe Myrtle, Native Sugarberry (I think), and some pine. Some of the growing is in the ground, some in pots and, some in pond baskets/colanders. There is actually a very good pictorial article on growing through tile in Bonsai Today 104 pg 30-41. It is far superior to anything I will post here.
Materials:
-4X4, 6X6 Ceramic Tile (Other sizes will work)
-Masonary Drill Bit (Bosch 1/4 in. Blue Granite Turbo Carbide Hammer Drill Bit; Im not sure if this is best, but it did the job)
- Drill
- Dust Protection (Im not sure what is most suitable for this application)
- Ear Protection
- Eye Protection
- Seedlings (or cuttings if you are the type that gets a high percentage of striking success
General Idea:
1. Drill a hole (or many) through a tile
2. Put a cutting or seedling through each hole so that all the roots are on one side only. I believe It is important to ensure all roots are below the hole in the tile so that existing roots do not become dominant above the tile.
3. Plant it in the ground or in a pot covering the tile surface with sufficient subsrate/soil to support new root growth.
4. Let it grow, the Bonsai today article says up to 4 years before root pruning. I would shape the trunk as desired.
5. As Smoke showed, as the tree swells/grows, the hole in the tile induces new roots forming at the constriction. These roots are forced to grow on the tile surface creating a flat nebari and fuse with nearby root growth if there are multiple trees.
Results:
After one year I do generally get nice radial root formation at the site of constriction and lateral root growth forming the beginnings of a nice nebari. In some case a couple roots appear to dominate. These may even out over time or corrective pruning may have to be used to ensure the desired effect is achieved. Certainly at some point the nebari will have to be touched up.
Concerns/Questions I have asked myself:
Do I have sufficient material (organic or otherwise) above the tile to maintain tender shoots through the summer and protect them in the winter?
When to prune the new roots?
Will this technique yield very similar safe bonsai every time?
Should I try varying spacing and angle of trees?
Does the sizes of the hole or seedling matter?
What types of trees are suitable for this technique?
I will be digging up some this spring and will post some of those pictures when I do. Oh, I also have a trick that may not be great, but is better than a busy background in pictures. I spray painted a large sheet of insulation black on one side and put gray mortar on the other side. It is a light weight two color photo backdrop that stores relatively easily. Its a little rustic, especially when I leave it in the dirt, but that is how I like things.
Results Pics on next page.
