I'd also be interested in trailing flowers.

Not familiar with your zone--but impatiens re nice here in my zone.

Not alot of long blooming flowers for shade except for annuals. Annual begonias and impatients bloom all summer, and coleus adds color as do hostas.

begonias, impatiens and coleus all make nice container plants that love shade. But they are more upright than trailing.

I like to grow chenille plant (acalypha hispida) as a trailing plant in pots. Does well in shade...

Another blooming, trailing container plant that does well in shade are the fuschia...hummers will eat from them.

We can't over winter most container plants where we live. But you can bring them indoors for the winter, and prune them back in early spring.

Here is a link that might be useful: overwintering a fuschia

This one is getting tougher to find. It seems growers are hybridizing our shade plants to need more sun. Last year I found New Guinie impatints and coleus with SUN markers on them!

Yardmartyr, I understand your username! My front porch is way to dark for impatiens or even begonias! I have to use foliage for color. You can try caladium, many nice colors, as is coleus. I also have hostas, rescued from the deer in the yard. In early spring, pansies work until the leaves come out. Some people recommend Heuchera, but that has died for me in pots.

An ornamental grass could look good for height. How about a small piece of statuary?

I routinely rescue deer buffet plants from my woods and put them in pots on the deck. These include False Solomon's Seal, Spring Beauty, Trillium.

Try to search the native plants database for your area. If you have a big pot they should do well.

Florrie

My front door is under a big overhang and so the area gets no sun at all. I have had great luck with double impatiens, they look like tiny rosebuds and flower profusely. Some years I have to go to a few garden centers to find them but this year they were everywhere. Some day I'll try starting them from seed myself but I don't have a good spot to do so right now. I have tried regular impatiens and new guinea impatiens with no luck. I have also planted pansies in the spring but they die by June. They're nice because they trail a little more.
You could try googling "annuals for dense shade." I have not tried over-wintering containers where I live, too cold.

There are trailing types of coleus and also sweet potato vine does work for me in the shade. You could also use snow on the mountain, that's very pretty.