In zone 7a Connecticut I'd like you to consider including more evergreen perennials.

I love a shade garden. Start with perennial evergreens as the bones of this garden so you have something to look at in winter when everything else is dead. Then lace in Solomon seal, ferns, hosta, coral bells so you have variety in texture and shape. You can get a surprising amount of color going with variation of hosta, fern, and coral bells.

I'm not a fan of boxwoods. They are so structured and at times very fussy. Too much shade and they can brown. Can you show a picture so we can suggest evergreen plant heights that will look good in this space?

Can you post a picture?

The hostas will lean, but it's fine, most people don't grow them for the flowers. Hostas will thrive in dry, dark shade. You can get them in all sorts of leaf colors, providing some variation in your bed. That said, hostas are boring and not native.

There are plenty of lovely natives that will thrive in your garden. I have a lot of Tiarella Coridifolia in my shady garden. I have Marginal wood ferns. Christmas ferns are evergreen. I don't water my ferns all that often. I have some Solomon Seal, Goatsbeard and lots of violets. The tiarella, violets and Solomon seal bloom in the spring, goatsbeard in the summer, and I have asters for the fall. You need to check the varieties for being native.

Anemones, Astlibe, Bishop's hat, and foxfgloves are flowering non-natives that could add some color.

Thank you for the wonderful ideas! What type of evergreen perennials would you recommend? I was hoping for something that is kind of tall - maybe 3 ft that I can space at intervals as it is a fairly blank wall. I am not at the house this week and unfortunately can’t take pics but here are some (blurry) old ones - I hope you can get an idea of the space! This is about 10 years old and the irises and daylilies are just cuckoo now

Also I’m not wild about coral bells… i love solomons seal and have some already so I can use that! I also love and have tiarella in the back but it seems to grow so slowly for me

Check out upright Japanese plum yew for a height candidate. I should say I have very little experience but I see them mentioned here often when evergreen and full shade are the topic. I think you should be able to find them locally even maybe at 3ft already. Slow growers and can be pruned and reportedly very deer resistant. Maybe over quite some years if they’re successful they can be a nice evergreen wall at a height of your choosing.

They take sun too and would grow faster in sun so you could still begin with them in that spot closest the driveway. They seem, at least from what I see in pictures, to maintain that smaller diameter near the ground for a while so shouldn’t impede your perennials for quite some time and if ultimately they get crowded out it just means you your yews look great and you don’t need the perennials anymore. I think this would take quite some years though.

It's been 25 years since I lived in New Haven so take my advice with a grain of salt LOL.

First, please do yourself a favor and endeavor to remove all the ditch lilies. It will probably take a couple of years to get them all. I've found them to be too aggressive to play nicely in a mixed border.

One of my neighbors has a border consisting of hellebores, ferns and liriope: simple and elegant. Since your border is beside the house, I think you could add dwarf nandina (no berries so not invasive). I recall pieris doing nicely in CT and that's a gorgeous shrub (if you can find a dwarf cultivar). Since you have a long growing season, I'd try to keep 2/3 of the plants in the border evergreen. Siberian iris has great foliage so clumps of that would be lovely.