I am using a plastic milk container. The front is cutoff and the inside is lined with screen for the crickets to climb. Very few crickets get out. Here's a vid on how to make it. There is also a thread in the enclosures section.
http://www.youtube.com/watch?v=h_od47TlbXA
I think it's a Rhododendron. Fairly common on LI. The bud in the middle looks like it could be the start of a flower. They are toxic so probably not a good idea for your Cham.