I notice service safe plants/tree have a issues growing without a grow light...so what plants/tree grow and actually look good in the cage?
I feel compelled to ask - why only plants that do well without added lights? Adding even a small bright CFL bulb of the right colour (towards 6500k which is slightly blue) on for a few hours each day to benefit plants wont harm the chameleon at all and isn't much impact on your electric bill either.
My pothos do fine without added grow lights, though those that get it certainly appreciate added light. But the ficus does much better with the added light.
I use cane plants that grow quite well just with the basking bulb and UVB. They are hardy and make it easy to wrap benda-vines around their trunk for cham highways through the cage. I pick mine up at Lowe's or Home Depot and they sometimes have a pothos planted in the bottom of the pot as a bonus.