I picked up
The Art of Keeping Snakes from Amazon. It goes into detail about keeping live plants in a vivarium, including which kinds will work and how to keep them alive.
Assuming the book is right, your first problem would be getting enough light to the plants. The book recommends plants in containers so they can be rotated in and out, so you can have one getting some sun while the other is in the vivarium. It's an interesting read, and has some useful info on corns and types of substrate and other things.