Fusing trunks

[AussieBonsai]

Hi all. I have a lovely little serissa which I am looking to being styling. My question is in regards to fusing the trunks. I’d like to create a mother/daughter design by approach grafting the trunks. My concern is that by wrapping raffia, etc around the trunks tightly, to pull them together, the trunks will graft, BUT will the force required of the raffia/wire, compress the trunks and case swelling, above and below?

 

[AussieBonsai]

 

[Shibui]

Short answer is yes. Often there will be swelling below and above the binding. Below is not too bad but above will show as reverse taper.
Is it possible to include 3 or more stems. That way some of the trunks above the binding can be pruned off after to recover the taper.
Otherwise watch carefully and remove and retie when swelling occurs.
Fusion has been touted as a miracle process. My experience is that I can fast grow a single trunk better and quicker than I can get a good trunk fusion.
What about alternatives? Get the tree out of the small pot and let it grow. Double the trunk thickness in a year or 2 without the worry of whether it will fuse or whether there will be reverse taper, etc.

 

[AussieBonsai]

I’m new to bonsai and so there will certainly be other methods that I need to read up on. Unfortunately I live in an apartment and so growing it in the ground is not possible, other than transferring to a larger pot, which I presume would have the same outcome. I would like to decrease the number of trunks though, without leaving marks at the base where I would need to cut. As such, I thought that fusing would solve both problems at once. Increase the girth and decrease the number of trunks in total, without scaring

 

[Shibui]

Fusing will introduce new possible problems. You will still have to prune but the scars will just be further up the trunk.
Unfortunately there is no magic bullet in bonsai.
Time can solve many problems but few of us have the patience to wait the required time. Pruning and quick growing can reduce the time taken but will introduce a new suite of drawbacks.

 

[AussieBonsai]

Would you prune at the base then, and grow out the remaining trunks over time (time isn’t really an issue) or if there another technique I’m missing?

 

[AussieBonsai]

I took my que from this tree and thought I would try the same. If you zoom in, you’ll see it’s been fused on both trunks

 

[Shibui]

Sorry but I can't zoom in on the pic. I'll take your word that it is fused.
Fusion is possible. Just that I have not found it easy to do well and without complications. Your tree looks ideally suited to what you have in mind so why not try?

When I look for images of serissa I find many with skinny trunks. If fusion was easy there would be many thick trunk images online. I have some serissa - all with skinny trunks but they are all the variegated type so maybe there is a faster growing one that will thicken quicker?
I have not found a way to speed up trunk diameter yet so cannot offer any technique.
My serissas all sucker freely from the base. removing suckers is almost a full time job. You can prune off excess trunks any time but you will probably then need to do the same again several times a year for ever after.