I would like to add Geranium to the mix. The native is G. maculatum. There are many others. How well any of them do is going to depend on the actual site and soil conditions in this dry shade. It will be a bit of an experiment. Do you let the leaves stay? How deep is the shade?

Depending .... part of your matrix may be the small to tiny naturalized weeds that grow on this specific site. That can vary widely and what you get is highly sun dependent.

Prairie Moon Nursey sells plugs, even in mixed trays The website and catalog is fun to browse.

In my climate/soil common violets are aggressive. I dusted off Rainer and was surprised to find that he recommends them for inclusion in the matrix layer of a planned plant community. So there ya go!

I second Christopher's suggestion of geranium maculatum. Lamium may also be a possibility for you. Please add spring bulbs.

Yes, the reason I'm planning to include common violets is that I have tons of them.

I've been trying to get my husband to leave the leaves. This year I succeeded.

The area gets little sun. In the middle of my yard is a ginormous copper beech, the area is between it and a row of tall hemlocks bordering the property. In there are some cedars, too and a black locust.

I have no tiny weeds there. I get garlic mustard, nightshade, herb robert? and another ubiquitous, non-native weed, which has orange roots and meadow-rue like leaves. Oh and dandelions and colt's foot and euonymous. Sometimes bittersweet and black swallowwort. Basically, a long list of weeds.

Plus, some aster which I'm pretty sure is native, which I will distribute so I have attractive clumps, not single weedy-looking plants.

My house is over 100 years old and the neighborhood was developed 100 years ago, from farmland or clear cut, so this is not genuine woods or the edge of woods. It's a border in deep shade on a smallish suburban lot with plenty (too many) 100 year old trees.

Epimedium does well in dry shade and there are several flower colors.

If you are going with a geranium as part of the planting matrix, then I'd opt for G. macrorrhizum before maculatum. Far more tolerant to dry shade conditions, foliage remains evergreen or nearly so, more likely to offer a rebloom and spreads by rhizomes to form a colony.

Will also second the suggestion for epimediums and Lamium maculatum.

I'd avoid the Lamium maculatum. It may be a lot more reserved than L. galeobdolan, but time will have its way if you turn your back on it. It will suppress other herbaceous plants growing in it as well as severely inhibit seed germination. You want your featured plants to self sow in the matrix if possible.

In a climate that is ideally suit to it, the lamium does not spread aggressively here at all. Nor does it have much of an ability to suppress or smother other herbaceous perennials.

And if the matrix is formed from primarily rhizomatous or naturally colonizing or ground covering plants, how necessary is the self sowing?

Here the L. maculatum forms dense mats that are very much self weeding, but yes, it does not spread at near the speed of the invasive one. Self sowing equals free good plants and herbaceous perennials do not live forever.

From a matrix planting standpoint, you don't want an overly aggressive community member. The plants are supposed to mingle and be layered by season. I would not want the Tiarella and Lamium competing for space. I'm not picking up that this is going to be an overly wild garden, however.

A bit late.. but solomon's seal, big root geranium , dicentra, autumn fern , brunerra are the the ones which have thrived in my dry shade garden. And right under the copper beach tree - sweet box is slowly spreading (apart from vincas , pachysandra, and daffodils )