Living in a very different zone where winter cold is not a concern for just about any container planting (other than annuals), I do much as Miz G describes. I focus on some sort of evergreen centerpiece - dwarf conifer, small shrub, etc. - then fill in with whatever else I like in combo. Usually some sort of grass or sedge, maybe ferns (if for a shady location) and usually heuchera or other evergreen perennial and a groundcover to drape over the side. And these all tend to be semi-permanent rather than just seasonal containers, usually staying as-is or the same for 3-4 years until I decide to replace the whole thing and plant the old plants in the garden.....or sometimes just toss them out.

I am not sure what to suggest for a cold zone like yours that would survive a winter in a container outdoors. Hardy dwarf conifers would be a good place to start but no clue what you could accompany them with that would survive winter cold in a container in your zone.

I have all containers. For winter interest, I have a dwarf blue spruce, an Arborvitae, bamboo, evergreen azalea and red-twig dogwood. I keep the flower heads on two hydrangeas.

my neighbor had a boxwood and some kind of hardy fern (cinnamon?) in pots and both died..I love the plants you're growing jana but the OP is zone 6 like me and I think we're too cold for most plants..I've overwintered hostas and macrophylla hydrangeas in pots in my shed but not outside..

Red twig dogwood is hardy to zone 2, and would be awesome anywhere, container or not. I had a yellow twig at my previous house but I like the red better. Will have that check that out. The dwarf blue spruce is zone 2 as well. Evergreen azalea might not survive, I think they’re zone 5. Probably not hardy enough in my zone for a container.

So I picked up a few things today. Carex, Gaillardia, Little Bluestem, and Sedum Autumn Joy. I’m going to try planting up the two containers and will see how they do. It’s a coincidence that some large containers that are usually available at walmart fit inside my concrete planters perfectly, so I buy them and spray paint them a concrete color so the bright colors they come in don’t show at the top edge. This allows me to plant different combinations and change them if one or another doesn’t do well, or for a seasonal change.

I have two other containers that might not be deep enough to support anything that needs a large root system. The PO had perennial herbs in it but most of them did not survive last winter, so I have annuals in it right now. Might be more cost effective to grow something from seed next year that I won’t expect to survive past one season.

I’m hoping they will look something like this in winter

Found this photo of Phlomis Russelliana, but maybe too tall at 3 ft. Miscanthus in the background.

For what it’s worth, here are my containers planted up. Will let them get comfortable in their pots then move them into full sun and then wait until the geraniums and calibrachoa fizzle in the concrete pots to swap them out for the fall. Carex, LIttle Bluestem, Gaillardia, and Sedum Autumn Joy.

Looks nice! Love your whole area there.

Update

In November I poke in all kinds of evergreens and winterberry. Stays fresh looking until spring when the tulips break dormancy.