Vinca groundcover, the green & the variegated, will do well in dry shade, & they can be planted without disturbing the crepe's roots too much.

Then just mulch.

don't dig in anything into the root zone of the crepes or the evergreens, & be careful not to raise the soil level.

trees & shrubs that are too deep never thrive, their bloom
is reduced, & they can even die.

Best luck!

I'd try to get some ground cover going and then perhaps scatter some pots of annuals?
You could use some plant stands or bricks or stones to get some some various heights to the pots.

Have you tried Homestead Verbena? It might not get enough sun there though.

We have a neighbor that has done what Melvalena suggested and it looks good.
I would say to do the same. Maybe you already know of a ground cover you like and add potted flowers. I have Hosta's in pots they need full shade and in the winter I don't have to worry about them another than checking for water once or twice in the winter.
Aster's would be a great flowering plant as well as geraniums.

Seems like everywhere I dig there are roots. Hopefully you can remove some little ones without too much trouble. Slide some daffodil bulbs in there, some blue eyed grass, and maybe you could squeeze a rosemary in a corner. Then add annuals in small pots. Marigolds, verbena (perennial), throw zinnia seeds in there (cut and come again). In the fall, sow lots of larkspur. You could put some echinacea, but it takes a few years to bloom from seed. With your root issues, you'd do well to think of using seeds.

Thanks so much all for the excellent suggestions, I plan on trying them all! I would be so discouraged without this forum!!

These are all good suggestions, but if you don't want ground cover and like to watch things change....

How much sun do you get?

Have you tried just diging it up a little and sprinkling on some seeds?

I have orange cosmos growing everywhere in part shade and some areas deep shade. YOu just water them in well and if you've scratched around a bit, they should be able to dig their roots in. In fall you can nestle in pots of mums, maybe cape daisey In spring you can set in pots of geraniums. In winter you could work in some wallflower.

Right now, there are 6 pks of marigolds everywhere. They take a small hole and I've had them live happily in part shade.

Another choice is lady in red salvia, but you'll have her everywhere.

Once you've enjoyed the summer / fall bloom, you can put in some bulbs for spring.

cynthia
who has little full sun from Easter to Thanksgiving, and plants everything under the sun in shade at least once.

Here is a link that might be useful: cosmic cosmos