I've got my cal king in a live planted viv, as well as my little green snakes. I've been looking at garter snakes, and would put them in with live plants as well. I do occasionally have to re-plant the plants in with the king, because he digs them up, but they seem to be doing all right. All of my frogs and salamanders have live planted vivs as well.

pictures!
the king's cage:


This is the old setup for my tree frogs and salamanders. I've got a few different setups for them now, and I'm thinking about using this for garters, with a slightly different layout.



I'm a huge fan of live planted vivs, even if the plants stay in their pots, which works well for some. Go for it!