Carrie, great article and a very good advice ! I'm using this method with some of my plants in the garden. For example, I'm going to divide the irises now and they will be fine in spring when it's their blooming time. I also planted a few rose cuttings under plastic bottles and they will grow very well during winter.
Bette, you just found the one who know all about the oleander. I have one too and I'm always trimming it back before I get him back inside . We have hard winters too here. Also, you may want to spray with an insecticide for pests and then make him a shower so he could be clean inside .