Thanks, Paghat, for a lot of new ideas, and for the
additional insights.

* Ground-cover that would trail down over the rocks. Creeping thyme
would do OK, I think,

nedds sun

It's thriving between the stepping stones in a path to the house door near
this area, so it seems that the 3+ hours of afternoon sun, and dappled in
the morning, is enough.

Lilies of the valley?

some ppl say that's a weed. (in wetter and/or shorter season regions)

It's OK with me - better to have lilies of the valley spread, than garlic
mustard.

You will have endless choices of shade plants if you can get water to
it regularly & deepen the soil, but as you say it is also rocky, I'm
assuming rather dry shade.

Well, there's been so much rain in these parts the last two years that
everywhere is a bit wet and the water table is very high in the whole
neighborhood, as tends to occur on small plateaus on a mountainside (this is
on the western side of the Blue Ridge), but normally this slope is
relatively dry. The water runs down towards, then around, the house. I don't
want to have to water the area except if some individual plants need to be
rescued during deep drought.

Cyclamen hederifolium loves dry shade conditions.

That sounds, and looks, great!

Epimediums (bishop's hats) are the premiere dry shade plants for
gorgeous leaves & interesting flowers. Many species & varieties,
they're worthy of becoming a special collection of different kinds,
among which might be dispersed Vancouveria hexandra or Vanouveria
planipetala for further variety.

Will start collecting.

Evergreen Iris foetidissima ("Stinking Iris" but it doesn't really
stink unless you bust open the roots) has subdued flowers as irises
go, but unlike other irises it thrives in dryish shade, & its autumn
berries are more impressive than flowers.

very dry summer tolerant. leaves bleach dry in sunny areas, unles well
waterd. will reseed nicely. easy transplant.

Scilla thrives in dryish shade, in the worst coerners where virtually
nothing else would be happy.

I have scilla all over the adjacent part of the slope.

Deadnettle/Lamium cultivars aren't as bad as you seem to have been led
to believe. They're not as aggressive as liriope

Sorry, I didn't mean to say deadnettle was such an invasive threat, but
rather soapwort. The latter seemed like the kind of thing that might get out
of control, spreading by seed, and compete with the springtime stands of
cutleaf toothwort, and small patches of rue anemone and wild geranium, in
the woods - native wildflowers that are hanging on, against the garlic
mustard and honeysuckle.

They only look their best in moist well draining loose
soil, though, & the fact that they don't die in imperfect conditions
doesn't speak to how awful they look if neglected.

Yeah, I don't like liriope, anyway.

Japanese anemones, one of the more spectacular perennials to flower
best in shade.

i've seen impressive swatches of white ones... tho they like water, so
never tried them. i've notieced them only on flat ground, as a bed
filling perennial.

Maybe at the foot of the rocks, where the soil stays moister.

Thanks, again!