No sun, no water, Ferns, epimediums and other Northwest natives can withstand the darkest, driest growing conditions

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1 With its tufts of pointed fronds growing to four feet or longer, sword fern (Polystichum munitum) is a natural in a woodland garden. One of the most versatile of all Northwest native plants, it adds striking foliage to out-of-the-way places, like dry shade. Photo courtesy of great plant picks No sun, no water, no problem Ferns, epimediums and other Northwest natives can withstand the darkest, driest growing conditions By Elizabeth Petersen When it comes to basic needs, plants require some combination of sun and water. Plenty of plants grow well and flower in shade if they get plenty of moisture. Think hydrangeas. Likewise, with plenty of light, an interesting assortment of plants can tolerate sun and drought. These creative water hoarders show off in a sunny xeriscape. But where both light and moisture are lacking, in those arid patches at the foot of thirsty trees, finding appropriate plants becomes a challenge. Understanding shade All shade is not created equal, so judging the degree of shade is an important starting place for pondering appropriate plants, said Richie Steffen, curator at the Elisabeth C. Miller Botanical Garden in Seattle, Washington. Unfortunately, there is no standard for evaluating shade, Steffen said, and people s perception on shade varies widely. Folks in the Northwest tend to think spaces have more light than they do. To talk about degrees of shade, Steffen has come up with definitions based on the amount and quality of light. He defines light shade as dappled sun all day or four to six hours of direct sun. By Steffen s definition, open shade has little direct sun reaching the october 2014 DIGGER 21

2 no sun, no water, no problem ground because of overhead trees. This type of shade still boasts a fairly high level of light and can accommodate golden-foliaged plants and those likely to burn in full sun. Medium shade has overhead trees blocking most sunlight from getting through. From the ground, only about one-quarter to one-third of the sky can be seen through the canopy of trees. Even here, Steffen said, there is still enough light to have a good selection of plants. Woodland favorites like rhododendrons will still flower, but the bloom will be diminished. And then there is heavy shade. Here, no direct light gets past the dense canopy of trees, and less than one-quarter of the sky is visible from the ground. In these conditions, Steffen said, few plants bloom well, so gardeners need to look to texture and contrast to make the garden work. Texture and contrast are design concepts for dry shade, Steffen said. Use mass plantings of plants with variegation, unusual foliage or dramatic textures. Simple plants like Fatsia, sword fern and Aucuba go a long way in making an interesting design. Right at home A number of Northwest natives are uniquely adapted to take a combination of dry and dark conditions, according to Sheila Kleist, owner of Trillium Gardens in Eugene, Oregon. A specialty wholesale grower of hundreds of species of source-identified wetland, herbaceous perennials and woody Pacific Northwest native plants, Trillium Gardens provides plants for public agencies, landscape contractors, other nurseries and garden centers. Deep, dry shade is one of the hardest conditions to accommodate, Kleist said. There are definitely plants that grow there and others that are adaptable enough to survive, she said. Sword fern (Polystichum munitum) is the very best option for deep, dry shade, Kleist said, an opinion confirmed by Nils Sundquist, owner of Sundquist Inside-out flower (Vancouveria hexandra) is a perennial that makes a great ground cover for shade. Its bright green leaves shoot up in the spring, followed shortly by small, white blooms. photo courtesy of great plant picks White wood aster (Aster divaricatus), another Northwest woodland native, bears lacy white flowers on purple-black stems late in the summer. According to Great Plant Picks, it s one of the few asters that tolerates some shade. photo courtesy of great plant picks 22 october 2014 DIGGER

3 Premier Supplier of Nursery Products Nursery in Poulsbo, Washington. Sundquist is a retail and wholesale grower of ferns, Epimedium and shade companions. He listed off the best ferns for deep, dry shade: First, sword fern; second, sword fern; and third, sword fern. Few other ferns come close to its resilience, Sundquist explained. The next-best ferns for dry shade on Sundquist s list are oak fern (Gymnocarpium dryopteris), spreading wood fern (Dryopteris expansa) and Asian saber fern (Polystichum neolobatum). All ferns want compost and mulch to aid in establishment, Sundquist advised, but many of the recently available xeric (requiring very little moisture) ferns such as Astrolepis and Cheilanthes are better in sun, partial sun or bright shade. Although some xeric ferns are reliably hardy to USDA Zone 7, none can survive saturated soils over winter. Site them like sedums or sempervivums in an open, well-drained location where their roots can run deep. Beyond ferns Kleist said plants that grow naturally with sword fern, such as Mahonia nervosa, can take the same tough conditions. An attractive relative of Oregon grape native to Northwest woodlands, M. nervosa forms a loose ground cover with shiny green leaves, panicles of bright yellow flowers in May, and waxy blue berries in autumn. Looking for something to plant underneath Douglas firs, where there isn t enough water for much to thrive? Consider Vancouveria hexandra, the inside-out flower. This low-growing West Coast native produces tiny white flowers in spring. Both M. nervosa and V. hexandra need water to get established, but then tolerate prolonged drought in the shade. Kleist also recommended Linnaea borealis (twinflower), a woody, evergreen ground cover that produces fragrant flowers in pairs, and Fragaria virginiana, the wild strawberry that takes very dry conditions in shade or sun. Shipping Materials - Stickers, shelves and pallets made to your specs, pallet repair boards, shipping gates, tilt sticks, used pallets Packing Supplies - Shrink wrap, banding Planting Stakes - Multiple sizes available Treated Lumber - Multiple sizes available SW Highway 18, McMinnville, OR october 2014 DIGGER 23

4 no sun, no water, no problem This hybrid epimedium (Epimedium versicolor Sulphureum ) makes a good ground cover for dry sites, or those with dappled shade. Its two-toned flowers range in color from buttery to yellow. photo courtesy of Great Plant Picks 24 october 2014 DIGGER

5 Japanese fatsia (Fatsia japonica) makes a striking impression with its huge, lobed leaves and sputnik-like flowers. According to Great Plant Picks, it does well in deep shade, and looks good in combination with rhododendrons or shade perennials such as hostas and hellebores. photo courtesy of great plant picks She also suggested yerba buena (Clinopodium douglasii), a trailing, evergreen herb native to woods near the coast from Los Angeles to British Columbia. The tolerant, low ground cover usually grows in shade as an understory plant, and its aromatic leaves are used as a general tonic. Salal (Gaultheria shallon) is highly adaptable and can grow where almost nothing else does in deep, understory forest groves, dry soils and deep shade. Buy established plants, Kleist advised, since bare-root plants don t take off as well. Thimbleberry (Rubus parviflorus) and mountain huckleberry (Vaccinium membranaceum) are both adaptable to dry shade too, Kleist said. Some native bulbs, which bloom in early spring before the trees leaf out and then go dormant in summer, $ frame $ frame 30 x 96 Semi Gable 6' On Center Bows 2 3/8" 13 Ga. 4' side walls, 13'6" high at center 48 X 100 6mil 4 yr. Poly... $ pcs Wire Lock... $ ' Roll-ups... $ pcs Wire Lock... $ Also Offering o Poly o Poly Carbonate o Shade Cloth o Exhaust Fans o Wire Lock o Heating o Ground Cover o Roll-ups o Bench Tops 20 x 96 Quonset 6' On Center Bows 1 5/8" 14 ga. 4' side walls, 8'6" high at center 32 X 100 6mil 4 yr. Poly... $ pcs Wire Lock... $ ' Roll-ups... $ pcs Wire Lock for top board... $ Specializing in Heavy Duty Greenhouse Frames Code and Non-Code (outside OR) ivans@ovg.com Fax Hwy. 99E Aurora, OR Prices good thru 10/20/2014 october 2014 DIGGER 25

6 GREAT PRICE GREAT SERVICE QUICK DELIVERY no sun, no water, no problem WE DELIVER! NURSERY WHOLESALE SAWDUST FIR BARKS CONTAINER MIXES CUSTOM BLENDS KILN DRIED SHAVINGS COMPOST $ 50 OFF Your First Wholesale Order! Just mention this ad! (New Customers Only) Always The Best Price Around! Delivery available throughout Oregon and California 7 days a week! prefer dry conditions and will bloom in shade, Kleist said. The best bets of these include Trillium, especially T. albidum, which can take completely dry sites, Erythronium (fawn lily), Fritillaria, Calochortus and Brodiaea. Epimedium has a reputation as an attractive, durable ground cover for dry shade. Sundquist believes that the drought tolerance of Epimedium has been somewhat overstated. Too often, drought tolerance is ascribed to the entire genus, said Sundquist, who has worked with more than a hundred forms of Epimedium. My experience has been that to perform well in the Pacific Northwest, E. grandiflorum, E. rubrum, E. youngianum, and most hybrids need water during summer drought. Really dry shade challenges all plants, Sundquist said, but the best epimediums by far for drought tolerance in shade are the yellow stoloniferous ones. These include E. pinnatum, E. perralchicum, E. versicolor and, to a lesser degree, the orange-flowered E. warleyense. They handle dry shade quite well once established, Sundquist said. Most all of the other epimediums are best used like Ericaceae tough workhorses, just not bulletproof. What other shade companions take dry conditions well? In addition to M. nervosa, Sundquist named Brunnera, Polygonatum and Saxifraga stolonifera as good performers. In bright shade, he also recommended Aster divaricatus, Aruncus aesthusifolius, Saxifraga Primuloides and S. urbium. All plantings need to be well established before they can truly tolerate drought. This means two or three years of watering during summer and well into the fall, since woodland soils can stay dry even after rains begin in autumn. Elizabeth Petersen writes for the garden industry and teaches SAT/ACT test prep at She can be reached at gardenwrite@comcast.net or satpreppdx@comcast.net. 26 october 2014 DIGGER