Leaving potted trees out for the winter

I've researched this a lot and always came up with the same thing; probably shouldn't do it.  So I left what I didnt plant last year out.  All winter.  Not buried.  No mulch.  Didn't even water them.  

Rats nipped most of them off one night but they did leave some alone.  

All.of them that didn't get nipped survived.  Many that were nipped survived also, but a handful didnt make it.  These things were as neglected as you can get!

Sawtooth, Concordia, and Jujube.