Ahhh...come to the plant master you have! LOL plants are my other passion! This specimen boys and girls is a butterfly gardenia or crepe jasmine commonly and Tabernaemontana divaricata formally. It is over 20 tears old and was my late grandmother's. I knew it from a seedling. Thanks for looking.
@KingGoodman. The gardenia grows fairly quickly at first about 6-8" a year but slows considerably around 3' and it is current 4.5 ft. It has grown only 6" in the past 3 years.
So if you could get a decent sized plant it wouldn't outgrow your enclosures.
The Christ in the manger grows quickly and actually loves being rootbound. And you can train the soft new growth quite easily. So it's perfect for chams.