I grow mine as a regular garden plant, and it is monstrously fast to reach 10 feet in height in just several years time. I suppose it could be treated as a bonsai, but the growth habit and character don't lend themselves to such training in my view. As the mature leaves are at least 18 inches across in addition to the 18 inch long stems, it will be a rather large bonsai...

Hi Andy,

Yes, Cussonia spicata makes a great bonsai! I have two of them. I am not really a bonsai person (scared to prune liottle delicate trees!) - but I treat them just like my succulents, in a well draining mix. The one has a single tuberous root, partially exposed, is in a 20 cm bowl and grows approximately 2 cm of stem a year, with cute leaves max. 18 cm across. The other has multiple tubers and 4 stems, is in a 30cm bowl (couldn't fit the roots into anything smaller) and is growing a little bit faster. Not sure yet if and how I should cut it back next spring.
They look good. Expose the tubers gradually and protect from direct sun when newly exposed.

I also grow a C.paniculata in a 1 m planter, as a feature plant. This one does grow at the speed and size any respectable Cabbage tree is supposed to! :-)

Good luck, you are going to like your bonsai!
maddy

Thanks for the info, guys. It's interesting what you said about multiple trunks, Maddy, as I noticed some buds on top of the tuber.
Thanks again.

My cussonia has grown very well over the past 10 years and has two trunks. It however outgrew the space I have for it in height and I have to consider to prune the tree to be lower and preferably grow more trunks. It is possible to prune the tree without killing it and how do I do it?