This is the first winter I'm hoping to have my bonsai survive. I live in Iowa and need to make something that is cheap but able to protect my bonsai from the frigid winter winds that usually start around January. Taking the suggestion of someone on another site, last year I tried placing my small, potential bonsai into the ground and packedd the bottom half of the trees with hay. That didn't work. Next spring I'd like to continue working on the trees I have in the hopes that some may become something nice to look at. Any suggestions for over-wintering?