There used to be some knowledgeable folk over on the trees forum, who may now have abandoned ship, but you could try your question over there. It seems to me that this is something you have to try first and know second.

I was hoping another gardener had dealt with one and knew what it's response was.

Hey, but it's flowering for the first time this year, wouldn't that probably indicate that it has to make laterals to grow past the flower petiole? hmmmmm

Said to be propagated by dormant buds cut out of main stem, thus the high cost when purchasing--material is limited and the stock plants get hammered in the process. If dormant buds can be gouged out and rooted, they should be able to sprout if top is cut back to point just above. In fact, that's what dormant buds are for, a backup system for replacing shoots after things like bears happen.

The variegated ones are Aralia elata, from Asia, of course, whereas eastern North American local native ones will be A. spinosa--unless you are seeing naturalized A. elata. So there will be some differences in structure and function.

Since the variegated cultivars may tend to be short-lived, apt to die back or wither I might be disinclined to cut one back. I have seen one trained to a single stem so it would fit next to a garage door, an effect I did not think enhanced the plant. Sort of like a spindly, variegated palm tree where a bushy evergreen that softened the corner of the structure would have been far more pleasing. But it did show that the plant could be trained into a different shape than usual.

bboy, I don't think this is a rooted cutting, It's making green suckers. It's been awhile since I bought it, but I'm sure it's a graft.

either way, I think I'll agree with you not to risk cutting it. Let's just wait to see it's response around the terminal panicles.

Yeah, the dormant buds would be used as scions--I don't know why I put "and rooted."