One way to get larger bonsai material is to fuse smaller figs together. Basically tieing together several figs that are genetically identical can produce larger trunks. Growing a tree in a larger container or in the ground will produce faster trunk growth but is often not suitable for indoor growers.
Fusion is a useful technique for rare or unusual materials and for adding in branches, roots etc. to a fig that needs these parts.
Bind the trees together with anything that will distribute the compression forces over a wider area to lessen scarring and use a binding material that does not stretch. Allow rampant growth of the materials to speed the fusion.
Marks left from the electrical ties can be reduced by allowing a year or two of un-restrained growth after the ties are removed.
For another article on this topic see http://www.bonsaihunk.us/FusedFig.html
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