Agreed, although if they find their way inside the pitchers themselves, it wouldn't be a catastrophe. Retf's would probably find a comfy spot on some bigger leaves. It also depends on where it is planted. If down low, tree frogs may never even go near it. But if you plant it high and allow it to cascade, they may hang out on the leaves. The big issue is really what I believe Grif mentioned about the soil and water.