Staking Amherstia nobilis

[Kaname-kun]

I was wondering about the growth habit of Amherstia nobilis. I have a small I think air-layered plant that has a short main trunk--maybe 10 inched?--and then two long branches forking off horizontally. It sends out new leaves regularly and seems to be doing well, but it doesn't seem to be growing vertically. A friend suggested I stake the two horizontal branches and gradually move them to the vertical axis. I'm just wondering how the tree grows--vertically or horizontally, Will that short main trunk eventually stretch upward? (By the way, the browned edges on the old leaves are from before I purchased the plant a year ago; it's doing very well here and no browning on any leaves produced since May 2017).  I'm attaching a photo . . .  Advice much appreciated!

[Mangosteen]

I have one growing just north of Hilo on the Big Island. Mine looked like yours when I bought it. The trunk did not change on mine, but new branches formed above the original ones and now the tree has begun to gain some height.

[Kaname-kun]

Thanks so much! I'd rather not torture the poor thing and just let nature take its course . . . 

[carmel]

Only one I have seen is at Fairchild.