If it's shady, you don't want to attempt lilacs - they need full sun! My experience with Duluth is very limited - visited once on Labor Day weekend and you had frost!........that is so out of my experience zone, I am hesitant to make any suggestions of what may survive in your area :-)

I would suggest visiting a local retail nursery or garden center and seeing what sort of shade tolerant shrubs they have on offer. Maybe something like the Northern Lights azalea series. Or Annabelle hydrangeas (Hydrangea arborescens).

And depending on the size of the planting bed now, you may need to enlarge. Most shrubs will require at least 4' of depth and if you need to get behind to paint or wash windows, etc., you will want to increase that to at least 6'.

ETA - you might want to post this in your regional Minnesota Gardening forum. I'm sure locals may have some additional suggestions for you.

I would recommend finding native shrubs. Go to Prairiemoon Nursery or some other online source that specializes in native plants. They can suggest plants that would be perfect for your conditions, and if they are native to the area, they are much more likely to thrive with little care. Also, they will benefit any wildlife in the area.

You know, it's simply not true that native shrubs or plants in general will be easier to care for or more likely to be uninteresting to local wildlife. I think of Ceonothus americanus, New Jersey Tea, which the deer love and is the ONLY shrub I have to protect during the summer. Or consider Trilliums, native orchids, bloodroot and native ginger, all of which the deer love.

Laceyvail, native plants benefit wildlife like beneficial insects and birds by providing food for them. Many insects, especially our native pollinating insects, have developed specialized relationships with the plants with which they evolved. Even seed-eating birds feed their young a diet that is about 90% insects, most of which are caterpillars. If we choose plantings that are not attractive to insects, then we will see declining bird populations. Some non-native berry bushes provide berries that are not in sync nutritionally with our birds' needs.

So, Adam, I probably don't need to echo the comments of others who have recommended native plants :-) You might also seek out any public gardens in your area to see what grows well there and what plants work well together.

I certainly have no objection to native plants; I grow a great many of them. I just don't want newbies to think that they are less likely to be eaten by deer or other wildlife or that that they are more likely to thrive.

Still have not decided on what to put in there.... :(

I was hoping to find something hearty (larger stem/stalk) because the dogs occasionally get their leashes wrapped around them and pull the plants apart.

Boxwoods do nicely for me on the north side of my house, zone 5. Don't know if they're hardy in your zone.

Just came in from my garden where the dwarf oakleaf hydrangeas 'Pee Wee' are in full bloom ... you might like these, and they're reportedly winter hardy to zone 5 with winter protection. They're more compact than the straight species, the leaves are among the first to open in spring, and in the fall they turn glorious shades of burgundy red with some orange and yellow. The flowers are in panicles (cone-shaped clusters), pure white now, will mature to pink.

You might want to do something, no matter what you plant, to prevent the dogs' leashes from becoming tangled and damaging your investment.