Landscape - Landscaping Dry Shade Areas

I have heard comments from landscapers that dry shade is the most difficult situation to design for. What follows are ideas for landscaping in dry shade.

Dry shade is the classic garden problem situation. Many yards, especially in established neighborhoods, have dry shady areas. When a shady environment is created by shallow-rooted trees there is intense competition for sun and moisture. Do not even try to grow lawn grasses in dry shade; they require both light and adequate moisture. In some cases, the best solution for very dry shade is only a layer of mulch or leaf litter. Even with a planted understory, don’t remove all the leaves—they add valuable organic matter and feed the natural soil system.

While most ornamental grasses require full sun, there are a few grasses and grass-like plants that tolerate shade. Crinkled hairgrass (Deschampsia flexuosa) and bottlebrush grass (Elymus hystrix) are two grasses that tolerate varying degrees of shade and dry soil. Pennsylvania sedge (Carex pensylvanica) is an excellent ground cover that tolerates very shady, dry sites and will even tolerate periodic mowing.

While most ferns require moist soil, there are a few ferns that will do well in dry shade. Eastern hay-scented fern (Dennstaedtia punctilobula) is so tough that it might become a garden thug under better garden conditions. Interrupted fern (Osmunda claytoniana) and Christmas fern (Polystichum acrostichoides) both tolerate dry conditions. Large masses of Christmas fern are often found growing on well-drained forest slopes. Two shadeloving asters, heart-leaf aster (Symphyotrichum cordifolium) and white wood aster (Eurybia divaricatus) thrive in dry shade. Just like the hay-scented fern, beware of wood aster and its ability to take over your garden under good conditions. Hyssop-leaved thoroughwort (Eupatorium hyssopifolium), tall white beard-tongue (Penstemon digitalis) Bowman’s root (Gillenia trifoliata), wild ginger (Asarum canadense), woodland phlox (Phlox divaricata), large flowered merrybells (Uvularia grandiflora), hairy alumroot (Heuchera villosa), golden ragwort (Senecio aureus), yellow trillium (Trillium luteum), Jacob’s ladder (Polemonium reptans), and bluestem goldenrod (Solidago caesia) will all tolerate dry conditions and partial shade. Some nonnatives are great performers in dry shade, such as barrenwort (Epimedium sp.), Hakone grass (Hakonechloa macra ‘Aureola’), and Lenten rose (Helleborus orientalis). Virginia creeper (Parthenocissus quinquefolia) is a vine that tolerates dry shade and will sprawl across the ground making a perfectly acceptable groundcover. Our native pachysandra—Allegheny pachysandra (Pachysandra procumbens) is another great dry shade ground cover.

It is harder to find shrubs that tolerate dry shade. Pinxterbloom azalea (Rhododendron periclymenoides) is a wonderful deciduous azalea with fragrant, white to pale pink flowers that is a must for the dry shade garden. Oakleaf hydrangea (Hydrangea quercifolia) thrive in dry shade. If you want evergreen foliage in your dry shade garden, try Piedmont rhododendron (Rhododendron minus).

Copied from "Liveable Plants for the Home Landscape", Authors: Susan Barton, University of Delaware, Sarah Deacle, Delaware Center for Horticulture, Gary Schwetz, Delaware Center for Horticulture, and Doug Tallamy, University of Delaware. For the full publication with photos go to http://ag.udel.edu/extension/horticulture/pdf/lowres18spreads.pdf