If your trees are deciduaous, you might consider things like trilliums, hepatica, virginia bluebells, trout lilies(erythronium), blood root, etc. Any library will have books of native plants, and shade plants.

Thanks. The trees are deciduous, and I've already planted some EARLY spring bulbs hoping to take advantage of early spring sun.

I'll go look it up in the library. I've been looking on the web and having trouble. One of the issues is that the area I want to fill had the boxwoods, so it's a bit acidic. I'm hoping that if I improve the soil, I'll have more sucess than the last people who lived here.

Feegle

My suggestion/recommendation would be to visit your local public library and see if they can either provide you with or interlibrary loan the following books. All three are fairly current, well illustrated, and with excellent descriptions.

If you wish to add them to your own library for future reference, you might search for these books at amazon.com; abe.com; or alibris. com. The latter two sources are excellent sources for finding used or new books in various conditions and various prices.

Hope this is more than useful.

Growing Perennials in Cold Climates by by Heger & Whitman;

The American Woodland Garden by Rick Darke;

An Encyclopedia of Shade Perennials by W. George Schmid

For vertical shade interest you could look at the aconitums and digitalis. Your choices for low-growing shade plants are vast. I garden in fairly alkaline soil, but gaultheria procumbens (don't trust my spelling too much) comes to mind as an acid-loving groundcover choice.

I would do a soil test before trying to change the pH of your soil. Boxwoods do prefer acidity, but they aren't indicators of it. Many shade plants will do well in slightly acidic soil as well. Especially some of the more difficult ones.

Bunchberry (Cornus canadensis), Wild Ginger (Asarum canadense), Pachysandra, Tiarella cordifolia cvrs. and sp., Heuchera villosa, Brunnera cvrs., Many Ferns, Astilbe 'Sprite' or 'Liliput', and Hosta cvrs. are a good start for low growing plants.

Aconitium cvrs., Kirengeshoma, Astilbe cvrs., Tricyrtis cvrs., Actea sp., Ligularia sp. and cvrs., and Cimicifuga sp. and cvrs. are good upright accents.

There are many many more you could use, and I haven't gone into specialty plants or accent plants. That would make this post very long. That's what books are for. :)

I second Schmid's book. It's one of the best gardening books I've read and I recommend it often. Rick Darke is an excellent author and speaker, I'm sure his book is great as well. I only glanced through it.