Definitely not. Echinacea (coneflowers) do not like to be overwatered and it sounds like that area is not only shaded, but stays damp. It is also probably too shady for coneflowers, daisies, and the others you have. I would try Ajuga (Bugleweed). It tolerates shade and moisture well though it will do best with morning sun. Gaura (Bee Blossom Flower) is another that likes it moist, though I'm not sure if you have enough sun for that one. Lamium (Spotted Nettle) is a nice foliage plant that likes full shade and moderately moist conditions. It makes a nice groundcover and you won't have to mow. It also produces flowers and is not considered invasive, though it grows fairly fast. I hope this helps.

Here is a link that might be useful: Shade & Moisture-Loving Perennials

If you have the space, snow on the mountain is a good choice for any soil (for me anyway) does like the shade, and will quickly fill bare spot. I like the back drop it gives to my part sun plants growing in front of it. It is a traveler but I just pull the unwanted ones when I see them. . .

Ferns, (esp royal fern), clethra alnifolia can take quite a bit of shade (growing where I grew rhodos/azaleas), lobelia sylphitica, impatiens (including the native I capensis)

Damp shade has loads of candidates - it's dry shade that's tougher to fill. Ferns have already been mentioned. Ligularias. Primulas. Meconopsis. And a lot of spring ephemerals like Dicentras, Corydalis and various bulbs, for before the maple leafs out. If choosing Lamiums don't get Lamium galeobdolon, now Lamiastrum galeobdolon. Go for Lamium maculatum cultivars. And keep adding compost to improve the soil.

This post was edited by floral_uk on Thu, Jul 10, 14 at 4:14

Thanks very much I will check all these out!!

Forgot Rodgersias and Kirengeshoma.

Another good choice might be Alchemilla mollis (lady's mantle). Lovely foliage and frothy chartreuse flowers in late spring/early summer.