With the exception of the oleander, over wintering them should be easy, depending on the size containers. If sufficiently large, there should be minimal need for any winter protection. If still quite small containers, you may want to group the pots and either wrap the containers (bubble wrap is ideal but burlap can be effective also) or bury them in a loose straw mulch.

I'm in a slightly higher zone, but I grow all sorts of trees, shrubs and perennials in containers on a permanent basis and the only things that get any sort of winter protection are those that are of marginal hardiness (like the oleander) or dislike winter wet. And those that prefer drier conditions only get moved undercover, not out of the winter cold.

fyi, there are crape myrtle now listed up to zone 6. try either wayside or park seed for their choices.

I'm in northern Alabama and overwinter containerized crapemyrtles every year with no problems. I wouldn't worry about the dogwood, either. If the temperatures threaten to drop into the low teens, I'd move them to the garage but other than that.....they should do just fine.

Oleanders? Nope. You'll have to come up with something different for them. They can take temperatures below freezing but severe cold can not only top kill them, but take out the root system, as well.

Overwintering crape myrtle and dogwood shouldn't be a problem, but you will need to bring the oleander inside. I would stay away from Wayside Gardens. They do not have a good reputation for quality plants or customer service.

I know this thread is a bit old... but how do you go about winterizing a tonto crape myrtle in a very large pot.. that cant be moved. I live in MASS

Hmmm - you've got a problem on your hands, and I'm going to chide you just a little for not taking that into consideration before you bought/established the planting.

It's hardy from zones 9-7, and because it's in a container, you have to worry because zone 5 plants are marginally hardy w/o protection (in containers) where you live. You're going to have to make arrangements to get it into a garage or other structure for protection - or rig an extraneous heat source, like a string of Christmas lights and a box to cover it and trap the heat.

Al