Snow on the Mountain grows in deep shade but is deciduous, it should overwinter fine in your climate as it grows in the midwest where I'm from, I also have it in California where I live where it comes back yearly. Snow on the Mountain flowers but they are not that noticeable. The less light it gets the better it does it seems. I also have archangel lamium which gets yellow flower columns on it, also grows in deep shade with glowing foliage. Though I'm not sure if it will overwinter in your climate.