The 'rules' guiding how we label our bonsai according to size are somewhat arbitrary, but you can use this as a guideline.

Keishi - up to 1 in (in height - top of soil to apex)
Shito - up to 3 in
Mame - up to 6 in
Shohin - up to 8 in
Kifu Sho - up to 16 in
Chu - up to 24 in
Dai - up to 40 in

Al

Thanks very much, Al. I did a little more digging and found a term (on a list of other japanese gardening terms) called 'hachi-ue' that means dwarf tree in a pot (deeper than the traditional shallow pot). Is that something you've heard?

Here's a link to a picture of my best hibiscus, double orange, about 37 years old at this point, trunk is about 2 inches wide.

Here is a link that might be useful: {{gwi:18960}}

Yes, I've heard the term. I have some trees in larger containers that I'm not really training as bonsai, yet I use bonsai techniques to keep them attractive.

Another term that often escapes us, though we know there is a word for it, is 'niwaki'. It is used to describe the training method used to create larger trees in the landscape, and for the trees themselves that we've trained to look like older scaled down versions of what they normally look like in nature - that we've trained to look like bonsai.

What a nice hibiscus. How long has it been in your care?

Al

The hibiscus shown was given to me 27 years ago, it was probably about a ten-year-old at the time, already flowering, etc.

Every other year, I take it out of the container and trim the roots pretty aggressively and prune the branches down to about 5 inches, at the beginning of warm weather. Then the whole growing process starts again, albeit with a thicker trunk each time. The first time I took the main root completely off and it's never grown back. The shock time gets shorter too, seems to recover better each time. I prune it about every 2 weeks (indoors) as well and keep the tips pinched, but let it go in summer (outdoors) where it flowers like crazy. Then pruning begins again as soon as it comes inside with just a few flowers thru winter.

I have a double yellow about the same size, but not nearly as old, probably around 18 or so, which I got from the local art museum greenhouse.

Thanks for your information, guess I'm getting info from an expert!