By Irene Virag
Imagine a place where there’s no irrigation, gnarled roots abound, and a canopy of towering trees blocks the rain and holds back the sun. In short an environment that strikes fear in the hearts of most gardeners.
It’s challenging for most plants because they have to compete with trees for water, light, and nutrients. Gardening under evergreens is hardest because the trees hold their needles year-round. The plantings beneath the maples, locusts, and tupelos that crowd what my husband and I call “the back 40”—it runs along the edge of our backyard—get sun and rain in autumn and early spring, but when the trees leaf out, forget it. Even then the tree roots suck up most of the moisture.
Our semiwilderness is a learning lab for dry shade. The trouble is I’ve been a slow learner. My only excuse is I’ve focused most of my attention on the large, sun-splashed flower/vegetable garden in our front yard.
In my defense I did start a shade garden in the back 40 years ago, and this season I’m returning to it with a vengeance. I’ve taken a hard look at what’s happening there and I’ve been surprised. Plants that have survived despite the harsh environment include Solomon’s seal, mayapples, hostas, liriope, and even shrubs such as kerria and oakleaf hydrangea. The denizens of my dry shade garden include classics such as hellebores. I have creamy-white and dusty-mauve varieties that bloom on the cusp of spring.
Also I have lamium, a carefree groundcover with silver-blotched leaves that look frosted, and springtime flowers in pink, white, or yellow. It roots easily and spreads quickly, enabling it to go forth and prosper in dry shade.
Daffodils I planted a decade ago have naturalized nicely amid a carpet of sweet woodruff, with vanilla-scented whorled leaves and tiny, white, star-shape flowers—a perfect groundcover for this difficult spot. I’ll be planting more early-blooming bulbs in the fall, especially snowdrops, chionodoxa, and scilla. Bulbs are perfect for dry shade areas because they soak up the food they need for the following year, then retreat to safety underground, all before the trees even wake up.
Other flowers, including bloodroot, bluebells, trillium, and trout lilies—a spring ephemeral with charming yellow blooms—kick-start spring.
Japanese anemones usher in autumn. But my semiwilderness doesn’t have to burst with blooms the whole season. Instead it weaves a tapestry of foliage and texture, with the help of plants such as wild ginger, and Japanese painted fern with sliver-and-maroon fronds.
And like epimedium, with nodding pink blooms and red-tinged, heart-shape leaves.
As it turns out, dozens of plants make the grade in dry shade. I’ll be moving in some of my favorites, among them lady’s mantle, with frothy, chartreuse flowers, and leaves that unfold like an accordion. And brunnera, for a touch of blue, and coral-bells (Heuchera), with elegant foliage in colors ranging from silvery green to almost black.
And I’m thinking about pulmonaria, with speckled leaves, and bigroot geranium (Geranium macrorrhizum), which holds its own from spring to frost with fragrant foliage, and pink or white flowers. There’s also leathery-leaf bergenia and feathery tiarella. And my wish list includes evergreens, like mahonia, with fragrant yellow flowers in spring, and blue-black berries and bronze foliage in fall; and Aucuba japonica, with glossy leaves that seem dusted with gold.
But even plants that survive and thrive in dry shade need some help, especially when summer heat gets to them and they show signs of wilting and they’re desperate for water. This goes double for newly planted blooms and bushes that need to settle in and establish roots.
You can help by limbing up trees so more light filters through to the plants below. When you’re planting, dig a hole twice the size of the root ball. But be careful beneath established but shallow-rooted trees—they won’t like their roots getting cut or covered too deeply with excess soil.
Also give the new additions a boost by mixing in compost when you’re refilling the hole, and water deeply during the first season. Add mulch to supplement nature’s own leaf litter, and top dress with compost once a year.
Oh yes, I’m planning to lay out a stepping stone path into my back 40 and find room for a bench, where I can sit under the cool canopy on summer afternoons and revel in my renovated dry shade garden.
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