Gardening Where the Sun Doesn’t Shine and the Hose Doesn’t Reach
by Marcia Tatroe
When I started my garden in 1987 shade wasn’t an issue. It was a goal. At the time there were only two trees on my property, a sick crabapple in the front yard and a small silver maple in the back. For a brief part of each day the house shaded areas near the foundation but there wasn’t one square foot of ground that could truly be called shady. Three decades on things have certainly changed. The chlorotic maple and the fireblight-ridden crab are long gone but a Ponderosa pine by the front walk towers above the roofline, and joined by another dozen mature trees have transformed my high plains garden into a woodland where sunlight is now at a premium.
Above: Viburnum x rhytidophylloides ‘Allegheny’
Above left: Pagoda Dogwood, Cornus alternifolia ‘Golden Shadows’ Above right: Tall white goat’s beard, Aruncus dioicus
This has had a significant impact on my plant palette. Expensive water and water restrictions due to drought and population pressures have also become a part of the equation. A fast draining, low-nutrient sandy loam soil with an extremely high pH further restricts plant alternatives, as do colder and more erratic temperatures swings than more urban parts of the Denver metro area. Discovering what will accept all of the above has turned my garden into a test plot where I’ve killed an uncountable number of plants otherwise considered reliable in a high plains environs. Still, enough survives to forge a highly diversified hodgepodge, more than enough to satisfy this obsessive-compulsive plant collector.
In my small, north-facing front yard I have gradually limbed up the 35-year old Ponderosa pine to allow in more light from the sides. A neighboring bur oak Quercus macrocarpa the same age would be taller than the pine by now if snow load hadn’t snapped it’s top off every few years. A stately twenty-foot tall hawthorn Crataegus laevigata ‘Crimson Cloud’ and a fruiting plum planted along the fence line provide more shade to the front yard. All four are easy to garden under without the masses of surface roots that make many other trees unsuitable.
Between the oak and the hawthorn stands the steadfast beauty Viburnum x rhytidophylloides ‘Allegheny’, a small tree that produces stinky but pretty lacy white flowers two or three times each season followed by glossy red fruit that ages to black. A white forsythia Abeliophyllum disticum planted the same year against the front wall of the house is just as tough and persistent, featuring fragrant white flowers on arching branches in late winter. Nearby, a variegated pagoda dogwood Cornus alternifolia ‘Golden Shadows’ looks like a gilded confection but it is actually one tough tree. Further down the wall stands Harry Lauder’s walking stick Corylus avellana ‘Contorta’, a hazelnut with oddly contorted branches and waterfalls of yellow catkins in late winter. Every spot where a fancy-leafed weigela, fothergilla, small hydrangea, or St. John’s wort has refused to live, I’ve filled the hole with a daphne, both species and hybrids in a variety of sizes, green-leafed and variegated white or gold – all with deliciously fragrant blossoms in white or shades of pink in spring or summer.
Above left: Variegated Daphne Above right: Bishop’s hat, Epimedium spp
A multitude of perennial flowers grow in shaded beds surrounding a central sunny, horizontal rock garden. Despite its reported thirst, goat’s beard Aruncus dioicus has performed without fail every year for 30 years, sending up white plumes in early summer to dispel the darkness beneath where sunlight never reaches. Reliable and long-lived winter-flowering hellebores, spring-blooming yellow Bishop’s hat Epimedium spp., various coral bells Heuchera ssp., foam flowers Tiarella ssp. and mountain primroses Primula auricula provide permanence as do groundcovers pink spotted dead nettle Lamium maculatum, yellow and white versions of variegated wintercreeper Euonymus fortunei, and blue plumbago Cerastostigma plumbaginoides. Two types of variegated Solomon’s seal Polygatum x hybridum ‘Striatum’ and P. odoratum ‘Variegation’ send up shoots here and there that produce dangling white bells in spring. Groundcovers can be overly enthusiastic gobblers of garden real estate but drier conditions slow their spread to manageable. Ephemeral self-sowing perennials like red-leafed Euphorbia ‘Chameleon’, pink- or white-flowered meadow rue Thalictrum aquilegifolium and golden Alexanders Zizia aurea create an ever-changing moveable feast of color, keeping things from becoming dull.
Above left: Foam flower, Tiarella ssp Above Right: Solomon's Seal Polygonatum ‘Far Reaches’
Above left: Red flowering currant Ribes x gordonianum
Above right: Coral bells Heuchera spp beneath an oak
In my predominately sunny backyard a few notables reside in shady spots, among them Colorado’s native waxflower Jamesia americana, a small shrub with glistening white flowers in early summer, tucked next to stepping stones leading downhill north of a pair of Austrian pines. The aspens that originally shaded the area died of drought ages ago. Two other favorite shrubs are boulder raspberry Rubus deliciosus with delicate white rose flowers in spring and flowering currant Ribes x gordonianum both sited in a corner between a large sumac and a fence where not much light gets through. You’ve probably noticed that the common denominator for dry shade shrubs is white flowers, so the currant is especially welcome for its reddish-orange blossoms.
These are just a few of the goodies that don’t just eke out a living but genuinely thrive in conditions most gardeners would consider impossible. The good news is that most of these plants will work for you, too (even if your soil is clay where the only trick is to amend with plenty of compost and/or raise the beds to facilitate run-off.) Clay-rich Front Range gardeners will find that their soil does a much better job of holding water and must be extra careful not to overwater.
For all of us it’s time to start seeing dry shade as an opportunity rather than as an obstacle. Especially as dry shade is the most comfortable place for the gardener to work on a hot day, protected from heatstroke and sunburn while dry enough to sit or kneel without getting wet in the process.
Marcia Tatroe is a garden designer, speaker, and author who scours garden centers and plant sales searching for something new to try. Some plants make it. Some don't but the quest never gets old!