The Hopi CMs that I have (I have four) are always the best bloomers and also the best for fall foliage. This year was not an exception.

My Acoma usually has dark purple fall foliage but this year it's trying to look like one of the Hopi CMs.

The Acoma against the backdrop of spruces

The Acoma next to several other colors including the bright yellow of a wild Sassafras tree that I've let grow

Claire

I read that too about Hopi and Acoma being cold hardy. My experience seems to agree with that. I first got three Hopi CMs back in 2001. We had an abnormally cold winter that year where temps at my place (obtained from my outside thermometer) got down below -10°C for several nights and below zero for an extensive period. Two of the Hopi died outright and the third lost all of its top-growth but threw out some new growth the next year from the root system. So, I bought 3 more Hopi in 2002 and those are the ones that I still have today. So I've had them a total of 7 years and they have survived several cold snaps. Their cold hardiness seems to be better than ever now that they are well established and their branches are really thick. I will occasionally lose part of a branch here and their during the winter but I've seen very little winter kill for several years. I tend to prune them back to a more rounded shape in the spring to control how big they get because they grow extensively each year. The Acoma was purchased in 2001 along with the three original Hopi. Even though it's more exposed (or at least it was then before the spruces next to it got bigger), it survived that really cold winter in 2001. It lost all of its top growth that winter but the roots survived and threw out some new growth. It's never lost any top growth since. It has an unusual weeping habit for a CM that is very attractive. I definitely have to prune it each year to keep it in bounds or it would become a real monster.

The cold hardiness of Hopi and Acoma is probably best illustrated when compared to my other two CMs, Red Rocket and Pokemoke. Both of these routinely lose top growth each year although they appear to be root hardy in my area. Having said that, the top growth of the Red Rocket has gotten better over the last two years maybe because it is better established. It's in a particularly exposed area so the fact that it survives at all is amazing. It has bright red new foliage that is very attractive. It bloomed for the first time this year. The dark red blooms were very attractive. It also has good fall color.

I'm in Marshfield. It's warm enough along the coast for them to survive here. It's doubtful that one would survive in your zone but with global warming who knows. I grew up in Alabama so they were ubiquitous there. I've always loved them and had to try growing some. They don't flower nearly as well here as down South but they still make very attractive shrubs and their fall color here is just beyond words. If you really have your heart set on one, why not try growing one in a pot. When it goes dormant for the year, you could just move it into an unheated garage or basement for the winter (while you continue watering it of course).