I have a very dry shady area that has the worst possible soil...tree roots, rocks, etc. My sister gave me a small clump of what I later found out is a groundcover called 'Ajuga'. In one summer it has spread like you wouldn't believe. I think they have it on the Stepables web site.

the ajuga's the shortest of them, I like it better as a lawn additive... but works under trees. Lamium (deadnettle) is another option- I have mine growing in through the pachysandras at my folk's house, and it's a real survivor : )

ivy will grow just about everywhere- but for me, that's the problem- it's a bit TOO common. maybe be stripey kind?

I agree that Ajugas would work well - there are many colourful varieties available.

I would also recommend Alchemilla mollis, Tiarella cordifolia and Heucheras.

It sounds like the area would also be suited by Hellebores and Iris foetidissima

Updated my list:
Mint
English Ivy
Violet( Viola Striata,V. Labradorica(Also Called V.Riviniana ), Others
)

English ivy and mint will not grow well in dry shade. I recommend false lily of the vally. It is supposed to prefer these conditions and will grow under hemlocks. I have finally found them for sale at Gardens of the Blue Ridge. They also have the more attractive Allegheny pachysandra.

Here is a link that might be useful: Link to web site

Think about Ceratostigma plumbaginoides, or Blue Plumbago. It grows about 8-10" high with rounded green foliage that turns a beautiful red in the fall. The sapphire blue flowers start in July and go until Oct./Nov. Loves sun or shade. It emerges late in the spring, so don't panic when you don't see it right away! This one is very hardy in Z5 so you shouldn't have any trouble with it. Spring planting seems to get it established easier. Good luck!

Myrtle aka vinca minor. Evergreen leaves, a leathery deep green, purple flowers in spring. One plant covered 60-80 square feet of dry clay ground under a maple, surrounded by concrete.

You might want to try planting HOUTTUYNIA cordata(Saururaceae) Look for 'Variegata' ('Chameleon') It has has splashes of cream, pink,yellow and red on the foliage. It does however need ample water. Good luck, Frank.

Bishop's Weed (Aegopodium), Lamiastrum, and creeping charlie are all pretty and pretty invasive.

Another that will spread wildly in dry shade is euphorbia -- robbii or chameleon are both good. They have neat succulent foliage, a bit less than a foot tall, with a cluster of chartreuse green (robbii) or maroon (chameleon) brachts above most of the summer. One plant will make a three foot circle in a summer. I am currently digging a bunch of e. robbii out of my iris beds, so let me know if you want it and I'll send you as much as you'd like -- I love it under my pinetrees up the slope.

LynnT

How about gout weed or Bishops weed? That stuff grows anywhere and it very difficult to kill out once you have it. On a brighter note, it does brighten up shady areas with it's variegated leaves. It spreads pretty fast too.

I love Lamium, (Nancy). It has great color and spreads nicely but not invasive in a bad way. Give it try!

I grow lamium, vinca and lily of the valley in dry shade.

Goutweed/Bishops Weed is my favorite -- it has variegated leaves and flowers that look just like Queen Anne's Lace. It loves shade and needs almost no water--it chokes out all other weeds. Just don't plant it anyplace you DON'T want it to spread!

dead nettle (lamium) the 'false' dead nettle...gooseneck loosestrife, and bishop's weed are all good, mint needs too much water, and violets never seem to fill in...

you might, however, want to try cyclamens, which prefer dry shade- you need to find ones that are grown from seed, though- not the tender ones from the greenhouse...

search for 'hardy cyclamens' I know there's a group that promotes them out there... they made it all the way to Martha Stewart one year.

Lamiastrum "yellow archangel" - nice variagated folliage and bright yellow flowers in spring. This can be very invasive but it can also be the perfect solution to a problem area. It is also hard to find. I ordered mine from Ohio. Let me know if you need a source.

Cricket

Try Polygonum capitata or hookweed. Grows fast , hardy , covers nicely , does not require much water,reddish foliage in sun but greener in shade. Mass of small pink flowers about 3 times a year , last for quite long. Grows easily from slips just stuck into the ground and watered.