Hands down hardy geraniums. All of them. They make everything look better-roses, hosta, peonies, clematis, etc

I believe peonies and lilacs are at their very best in my cold winter Great Lakes influenced area.
Forsythia is a lovely thing and a herald of pruning time for roses.

Steven

Here, hardy geraniums like Rozanne, and asters are fabulous. Lilacs are wonderful. Euphorbias and lavender are wonderful but trimming is high maintainance.

Melissa, thank you for starting this. About 3/4 or more of our property is shaded and our soil is dry, rocky, infertile and acidic. Our yard slopes to southwest. Cyclamen do well here, too, even self-seeding politely in our front lawn. So do hellebores, especially the lenten roses. Ferns, especially the Christmas fern and the Japanese painted fern have spread under the camellia and around the hydrangeas. I think the most surprising volunteers are the biennial foxgloves that can sprout in places where they haven't grown in nearly a decade, American heucheras that I started from seed several years ago have also started to fill in and self-seed. All of the above could grow together to make a lovely shady border with no effort at all on my part. Deer will rarely nibble on the heucheras during a drought but usually leave all of these alone, for the most part.

I try to save the sunny places for fruit and vegetables. Whatever is left is for flowers, including roses. My favorite companions for roses are flowering herbs which have the dual benefits of attracting pollinators and repelling deer. I love salvia for this, especially salvia coccinea. Over a decade ago I planted both the red and pink varieties from seed but have never needed to do so again. It doesn't winter over but never fails to self-seed. Every summer the local hummingbirds fight over the stands in each border.

I am not an experienced gardener and am still experimenting, but my favorite are poets jasmine and rangoon creepers. Poets jasmine bloomed through the year pausing only during the coldest time of the year for a couple of months, stayed evergreen. And the fragrance is amazing and wafts. Rangoon creepers are not evergreen, but blooms with such exuberance and pretty colors through the warmer months, the single one is still blooming for me and the double just paused. No trouble or disease etc with either, and they do so well even in a container.

Lycoris squamigera (much underrated), Helleborus niger and Colchicum. Other lycoris are lovely too (google L. chinensis) but are not as rock solid durable. L. squamigera bulbs have multiplied in the woods from 2 bulbs to about 180 stalks last year. This was over 40 years but it took me about 30 to figure out that they prefer shady and damp over dry and sunny. Most prefer Helleborus x hybridus and it does seed much more readily giving fascinating multitudinous color changelings. Still I prefer H. niger 'Joseph Lemper'. It is blooming now when nothing else is and has been here long enough - maybe 10 years - that the clumps have multiple blooms and are becoming showy. And white is my favorite flower color. The Colchicum: hmmm - the criticism has been made, and justly, that they flop. C. cilicia does not appear to because the flowers are smaller and the stems shorter and I like it a lot. Yet my favorite is C. byzantinus albus. I think what I have is perhaps a clone because it is much larger and more seductive than the C. byzantinus which is pink. The C. autumnalis alba is nice, coming last.

As I write more plants pop into my mind: earliest (always a plus) Eranthis hiemalis and Galanthus plicatus byzantinus ssp byzantinus ex. Colesbourne, then late summer Anemone japonica 'Honorine Jobert' and 'Whirlwind' (a double), both white, which bloom until frost. August into November bloom is not shoddy. Then there are box and yew which act as staging for the flowers creating the "bones" of the garden, the surrounding greenery. Neither require much care except shearing and both are easy to propagate. Then there are herbs for scent and flavor, fresh figs and cornichons - discovered this year - a different species of cucumber and the crispest I have ever tasted. I had better stop. We could be here all night.

Cath

Cath, thanks for refreshing this thread; and thanks to everyone who wrote in! I have a lot of the plants you all have mentioned, and Cath mentions some I'd like to have (Japanese anemones), or would have, or have in better shape, were it not for environmental factors (colchicums and porcupines; box and box moth). It's so pleasant to hear from Steven and the chilly north--I was in the northern midwest once in the spring and it was glorious--but people have written in from all over, which is satisfying.