I have a similar area where I planted sword ferns, hellebore and hosta. Every so often the area needs a little raking because the pine needles, cones and debris from the trees build up quite thick.

Is this dry shade or wet shade? also is it deep shade or filtered shade?

If it's under fir trees (or any other conifers), it's dry shade :-)

I like Euphorbia robbiae for this kind of situation - it's evergreen, has some height to it so the needles drop beneath, is very tolerant of dry shade, spreads well but not too rampantly in these conditions and needs virtually no maintenance. I just trim back the old flower stalks once a season or trim it back if it gets too rowdy and that's it. Bright chartreuse yellow flowers (bracts) in early spring. Best if planted on its own as it can overwhelm smaller plants.

My favorites for dry shade are ground cover comfrey, Symphytum grandiflorum; and Geranium macrorrhizum; and needing a little more water, Epimedium. If you wanted an ephemeral that is covered with flowers in spring, then disappears in summer, Anemone nemerosa comes in several colors.

Here is a link that might be useful:

My favorite dry shade plants are Sarcoccoca. S. hookerania humilis is a ground cover. It's evergreen, with tiny but very fragrant flowers in February. I also like to have various cyclamen in dry shade.

Whatever you do, don't let anyone talk you into ivy.

I forgot to mention the native Mahonia nervosa, Long Leaf Oregon Grape. It's low growing as is the M.repens, but I've had better luck with the M. nervosa.

I have to second gardengal48's suggestion. I love Euphorbia robbiae. Yesterday I was out in the garden doing clean up and saw my little stand near a HUGE Ceder tree. It looked so good. It is so dark green with perfect foliage and budded up getting ready to bloom. Such a wonderful plant in the right place! I also love our native sword ferns. They seem to grow anywhere with minimal maintenence. My experience with Hostas in that situation is that they look great the first and second year then they slowly get overwhelmed by the tree roots unless you keep amending the soil and keep them watered. Note I said (my experience). Maybe others have had continued success and I would love to hear about what they do!

i'll second mahonia nervosa with some caveats. its pretty hard to establish unless you get pretty big plants. they are slow growing and often get lost before they get big enough.

you can transplant them out of different national/state parks, usually with a free permit. you need to take a LOT of root mass for it to work, they don't transplant well.

You could always come to my house and dig up some salal! LOL! That's a slam-dunk groundcover for this situation - native, evergreen, grows under these conditions naturally and easily. I will have lots to share, as I am digging it out from under a large western red cedar as well and will replant with the Euphorbia (great minds think alike, Mary :-)).

I love our native sword ferns and hellebores in dry shade under my neighbor's firs and arborvitae.

Bamboo Mary, I thought I was the only one who experienced the mysterious declining hostas.....My experience with hostas in dry rooty shade under conifers is that they decline every year until they don't come up at all. Even with hand watering (there are soaker hoses too)

carex 'Ice Dance' does well in conifer shade soil

The shrub Aucuba would also grow there. Sometimes because almost nothing grows tall enough under Fir trees, privacy is an issue. With a little attention paid to watering the first year or so, Aucuba can grow up to six or eight feet tall in a reasonable time.

Mahonia nervosa is slow to establish itself, but looks nice once there.
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I'd like to try some of that Euphorbia, but worry about it's invasiveness.

In dry shade, the euphorbia is no more invasive than the mahonia or the salal. Put it in more sun, in rich soil and with regular watering, you might have a problem on your hands :-) OTOH, it is far easier to remove where not wanted than say the salal.

euphorbia is easy to remove, however remember to wear gloves and eye protection.

removing euphorbia is probably safer than driving your car, but be aware people have gone blind, gotten horrible blisters and even died from being careless with that plant.

Let's not get too carried away :-) Fatalities associated with euphorbias (which is a HUGE genus, btw, and with widely varying degrees of toxicity among the species), are pretty much limited to those who ingest the plant. Some species are considered to have certain medicinal properties and are processed/consumed for that purpose in many third world countries that practice a lot of folk medicine.

It is the latex sap that is of concern to those of us that garden with hardy euphorbs but tend not munch on them. And the reactions to that sap, which is quite caustic, will vary with individual sensitivity. It can (doesn't always) cause skin reactions and will irritate mucus membranes and eyes if allowed to come into contact. Wear gloves when working with euphorbs - a standard recommended garden practice regardless of plant - and keep any parts away from your face and mouth. Wash your hands thoroughly after working with the plant.

It's OK.........really :-) No more dangerous than using various common household cleaning products and a lot safer than some.

Salal is a great plant if it's got LOTS of room, but, while it is a groundcover in the sun, it becomes shrubby and tall in the shade.

well, thats why i said that dealing with euphorbia is about as safe as driving. with standard precautions you should be fine. just be aware of what they are!

i got nasty face blistering before i knew what that sap did.

Gopher Purge euphorbias have given me and guests skin blisters somewhat like poison oak, but I haven't noticed problems with other euphorbs. It can be rather upsetting to mothers who leave their infants in your care when large water blisters like burns pop up on their little pink arms after just a casual stroll around your yard. Ouch.