Hi franeli, I have two purple leaf sand cherry shrubs that I prune to the shape of small ornamental trees. Good through zone 2, they've been nice focal points and have a lovely little white flower in the spring.

Google images shows the different shapes that this tree/shrub can take.

Jane

Here is a link that might be useful: Missouri Botanical

Sorry about your wine and roses weigelas, thyme2dig!
I'll check out both the ninebark and sand cherry. I'm guessing there is a high probability that voles might girdle the cherry. Voles have also girdled a lot of my hedge of dwarf lilacs. I still have half the yard under snow, so, I better toughen my nerves.

Both the weigelas and the lilacs will probably grow back unless the voles ate too many roots. If you can afford a bit of patience and they do grow back, you can try the voles discouraging remedy that Gardenweed posted last year. I've found it works pretty well as getting the voles to decide they would rather be elsewhere.

I have a dark purple foliaged elderberry AKA Sambucus, 'Black Lace' I think. This will be its third or fourth season, and it has been trouble free and undamaged by the voles so far in a bed that has way too many of the little varmints.

One perennial that might work is Actea (formerly known as Cimicifuga.) There are dark foliaged forms like 'Brunette' and 'Hillside Black Beauty' among others. Before planting where you might brush against it, see if you find the foliage odor unpleasant. I was glad that mine was planted near the back of the bed. It is happy in sun or shade IME.

Thanks nhbabs! Great ideas and information. I'll most likely look for some kind of substitute for the weigelas because
every winter there is branch and bud dieback and now 90% of the branches are rodent girdled at ground level.
Those perennial ideas are grand; beautiful plants if I can find them.