A few things come to mind. In my full shade bed I have close to a dozen assorted hostas along with:

Athyrium nipponicum/Japanese painted fern
Alchemilla mollis/lady's mantle
Brunnera/Siberian bugloss
Heuchera/coral bells
Astilbe/false spirea
Carex morrowii/Japanese sedge grass (Z5-9)
Cimicifuga racemosa/black snakeroot*
Hellebore/Lenten rose
Aquilegia/Columbine
Polygonatum odoratum var. pluriflorum âÂÂVariegatumâÂÂ/
variegated Solomon's seal
Tricyrtis hirta/toad lily*
Pulmonaria/lungwort

* late-season bloomer

Unless otherwise noted, all of the above are hardy to Z3 or Z4.

Just as a side note, I don't rely on flowers to provide impact in my shade beds and look instead to foliage for contrast, color & form.

Good luck & have fun!

Thanks for the good advice. Here's a more recent picture taken from a different angle in the late afternoon. It' not full shade, but Moore shade than sun.

Those foxgloves look happy. Unfortunately, they don't like my acid sandy loam and therefore even seed-grown plants were short-lived.

There are many sun perennials that do well in less than full sun so long as they have healthy soil and sufficient moisture. As an example, I have seed-grown Buddleia/butterfly bush as well as Perovskia atriplicifolia/Russian sage planted in both part sun and full sun and notice no difference in the quantity of blooms between them.

Trollius ledebourii/Chinese globeflower does well in part sun as does Persicaria virginiana/Fleeceflower âÂÂPainters Palette.' Actually, daylilies are also thriving in several of my part sun & mostly shady beds as are hardy geranium and Polemonium/Jacob's ladder. Wish I still had Photoshop and could share some pictures of my garden beds. Even Platycodon grandiflora/balloon flower is apparently happy in less than full sun, at least in my garden. Then again, hosta is happy as well in more sun than I'd normally think to give it.

Once again, Mother Nature knows best.

One thing to be aware of is that the bleeding hearts will die back in mid to late summer, leaving a bare spot. So as you add things, you might want to add something that sprouts late and would help fill or disguise those areas.

I grow most of the plants gardenweed listed in my partly shady areas. Others I have include
dwarf crested iris (Iris cristata)
European ginger (Asarum europaeum)
woodland phlox (Phlox divaricata)
partridge berry (Mitchella repens)
Heucherella
Tiarella

If there are spots that get more than 5 hours of sun, one of the clematis that tolerates some shade could be planted with an obelisk or trellis for it to climb. Most of them will bloom for several weeks in the summer.

I can't tell if there is enough room, but you might want to add some small shrubs. With just a few hours of sun, you can grow and get flowers on some of the smaller rhododendrons or mountain laurels (though the full sized ones would be too large) if you have acid soil, and they would give you some winter interest. There are hydrangeas such as some of the reblooming H. macrophylla (bloom on last season's and this season's branches) such as Endless Summer which even if it is killed to the snow line as it is most years in my garden, will put out new branches and bloom for much of the summer. There are some small H. paniculatas like 'Little Lamb', 'Little Lime' and 'Little Quickfire' which are fine in full sun to part shade, and will bloom from late June through hard freeze. They start light green and progress through creamy white to pink in the fall.

Perennial geraniums would quickly fill in that area, spill over the wall in a very cottagey way, and can easily be plucked back to within whatever boundaries you want them to stay within. They do bloom in spring, but they have the advantage of staying neat after you deadhead, and they have red/orange fall coloring to boot! This pic is old, but shows the magenta geraniums to the front of the bed by fencing. I have used pieces of this plant to fill in bare spots at the font of borders and it is perfect!

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