Hi
You could do something like this
It is basically a planter upside down then a planter on top with a plant then slate or rock for them to climb up on.
Or you could do this
But yes you will have to make sure they can not climb up on that ledge and fall off.
As for over wintering
they will over winter outside what they do is go down to the bottom and hibernate threw the winter.
They have the capability to breath threw there skin.
But still if you want to bring them inside in winter that can be done also.
Ruben