Ferns bring as their gift to the garden serenity, peace, and a unifying green calm. Sue Olsen, Encyclopedia of Garden Ferns

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1 Ferns forever Whether a dependable native workhorse or a dazzling specialty selection is called for, ferns fit the bill Licorice fern (Polypodium glycyrrhiza) clings to an outdoor archway early in the spring at Bosky Dell Natives in West Linn, Ore. Nursery owner Lory Duralia is a big fan of the fronds due to their utility in landscapes. Ferns bring as their gift to the garden serenity, peace, and a unifying green calm. Sue Olsen, Encyclopedia of Garden Ferns By Elizabeth Petersen Ferns fit right into current garden trends of using both native and heirloom plants. Easy-care and dependable, ferns grow almost everywhere. 12,000 native fern species appear in all sorts of conditions on every continent except Antarctica. And ferns are among the oldest surviving plants, dating back millions of years. Besides being practical, ferns provide texture and color, in groups or alone, in woodlands, in naturalized plantings or in practically any shady space. They work well in containers too. And advances in propagation techniques are helping growers bring better selections to market. No wonder ferns are gaining attention. At home in the woods The Pacific Northwest is a good place for native ferns. Evergreen sword fern (Polystichum munitum) blankets forest floors, thriving in the dry, deep shade beneath huge conifers. Native licorice fern (Polypodium glycyrrhiza) clings with 24 JUNE 2012 DIGGER 23

2 Ferns forever Licorice fern (Polypodium glycyrrhiza) is native to the Pacific Northwest and prefers damp, mild climates. moss from trees and rocks in early spring. Well-mannered deer fern (Blechnum spicant) decorates moist, shady, acidic sites in Oregon and Washington, and sheets of delicate maidenhair fern (Adiantum aleuticum) cling to banks and the walls of canyons. Lory Duralia, owner of Bosky Dell Natives in West Linn, Ore., supplies large numbers of these ferns for restoration projects, schools, homeowners and nurseries. Everybody likes ferns, she said. Native ferns thrive on neglect, require almost zero maintenance and work well as understory for tough spots. They hold banks in place, help control erosion, handle dry conditions beneath big trees and provide protection places to hide and stay warm for wildlife. Ferns are a good replacement for invasive

3 English ivy, too. As people understand the importance of native plants to sustain wildlife, demand increases, Duralia said. Plenty of ferns native to other regions produce good results, too. Writer and fern nut Sue Olsen has studied, propagated and written about the world s ferns since the 1960s. She owns Foliage Gardens in Bellevue, Wash., the oldest mail-order nursery offering spore-grown ferns in the U.S. Ferns are immensely more popular now than when I got started some 40 years ago, she said. At that time, one couldn t even find an autumn fern (Dryopteris erythrosora) on the market. Now it is everywhere. I expect this trend to continue, especially as folks discover more variety in avail- 26 Deer fern (Blechnum spicant) grows at Bosky Dell Natives in West Linn, Ore.

4 Ferns forever Favorite ferns Our sources recommended a large number of ferns more than we have space to tell you about here. For a sampling, read on. For the entire list, log on to Sue Olsen, Foliage Gardens, Bellevue, Wash. Adiantum aleuticum (western) or A. pedatum (eastern/northern). For a woodland feel, it's hard to beat native maidenhair. Easy despite its delicate appearance. Athyrium otophorum, eared lady fern, is an excellent fern that adds refreshing color to shaded woodlands with protection from direct sun. New growth has radiant lime and burgundy fronds that soften to a more subdued gray-green patina. Dryopteris erythrosora, autumn fern, is held in highest esteem for its universal adaptability and brilliant contribution to the garden s panorama. A top recommendation for beginners and experts alike. Polystichum neolobatum, Asian saber, long-eared or shiny holly fern, is one of the best evergreens for year round interest, ease of cultivation and handsome foliage for shade. A truly aristocratic jewel, it is well behaved, reliable and beautiful. A top choice for gardens throughout temperate regions, its inch fronds are very glossy, narrow and dark green. Nils Sundquist, Sundquist Nursery, Poulsbo, Wash. Cheilanthes sinuata syn. Astrolepis sinuata, wavy cloak fern, is drought tolerant. In desert or scree, ferns survive dry habitats by sending roots deep into a cooler root run to obtain moisture. Excellent for brighter, drier sites with fast drainage. Polystichum polyblepharum, tassel fern, is more refined and ornamental than sword fern with high gloss, uniform fronds. Also shade tolerant. Polypodium scourleri, leather polypody, is a stunning Pacific Northwest native that makes a great alternative to Licorice fern, another native that goes dormant in summer. Scourleri boasts stiff, leathery, oblong leaves. Ketch de Kanter, Little Prince of Oregon, Aurora, Ore. Dryopteris kiodzumiana a new addition to the line-up at Little Prince, resembles autumn fern, but has impressive, brighter red new growth. Polystichum setiferum Proliferuum Wollastonii has dense, long, lacy soft green fronds. People are onto how cool this plant is; they buy a lot. Kent Kratz, Casa Flora, Dallas, Texas Dryopteris erythrosora, cultivars of autumn fern, produce colorful new fronds. Brilliance is one of the showiest with glossy fronds that emerge bright copper red and change to dark green for summer and winter. More colored frond Dryopteris are in the pipeline. Polystichum spp. offer many nice selections including small, lush Korean rock (P. tsus-simense) that has a delicate, graceful look and can withstand dry spells. Dyce s holly fern (P. dycei) produces large, dark green, glossy fronds arranged symmetrically around the crown. A fast growing focal point. Woodwardia unigemmata, jeweled chain fern, is a new, unique selection that was rare before tissue culturing. It boasts huge, reddish new fronds and easy, fast growth in the garden. Autumn ferns (Dryopteris erythrosora) are a favorite because they are very forgiving for the gardener and offer interesting color. According to Ketch de Kanter at Little Prince of Oregon, several cultivars are available with interesting coloring, and more are on the way. ability and see ferns in gardens and public displays. People should not be afraid to use ferns or to try new ones. Most are low maintenance and many are drought tolerant once established, Olsen said. There s great variety in size, site requirements, texture and effects. Not only that, but using broad statements of green brings unity to a colorful garden. Nils Sundquist, owner of Sundquist Nursery in Poulsbo, Wash. agreed. With reliable performance and interesting foliage, some fern or other will fit nicely into the partially shaded, empty spot that exists in most gardens, he said. Sundquist, who offers one of the largest selections of ferns in the Northwest (usually about 50), also reports increased enthusiasm for ferns. The selection available from growers continues to increase. Little Prince of Oregon, a wholesale grower based near the town of Aurora, grows ferns for low-light areas and sells them in 3½-inch pots under the name Made in the Shade JUNE 2012 DIGGER

5 1 (800) C E L E B R A T 151 Varieties of Fern E S T A B 46 YEARS L I S H E D I N G

6 Ferns forever Ferns are underutilized in gardens and landscapes, but they are a growth market for us, nursery owner Ketch de Kanter said. We sell more every year and try to bring more variety to our customers. Those customers include retail garden centers, landscapers and other wholesale growers. Koidzuma's wood fern (Drypoteris koidzumiana), available from Little Prince of Oregon nursery, is similar to autumn fern. Like autumn fern, the new growth is red, but it is a brighter shade of red. Fern production Ferns are a very good supplement to our other lines, and in nursery production, they are carefree, don t seem to be susceptible to bugs and if they don t sell, they die back and start fresh again the following year, de Kanter said. Little Prince hand waters to assure that ferns are neither under- nor overwatered and uses a special fern mix that leans toward the acidic for ferns It s still Acers to Zelkova, plus new Elms & more! Value pricing on all our ornamental seedling & cutting liner varieties. WE SPECIALIZE IN UNDERSTOCK FOR FLOWERING, FRUITING & SHADE. Our customers come to us for our quality rootstock. They come back for our service and attention-to-detail. see all of our new offerings, plus current availabilities at canby, oregon T O L L F R E E : E M A I L : Willamette@canby.com 28 JUNE 2012 DIGGER

7 Premier Supplier of Nursery Products and other native plants, de Kanter said. Little Prince offers both sword and deer fern that has been collected bareroot, but both Sundquist and Little Prince bring in plugs of other ferns (some spore-raised, some tissue-cultured) from specialty producers to get a head start on growing from spores. Ferns are an ancient evolutionary odd duck, Sundquist said. From spores, they spend their first growing season looking something like a flake of liverwort. The second season, they develop roots and can be transplanted into pots. They re slow to size up. Unlike other fern growers, Sundquist grows mostly #1 and larger sizes. For many uses, people want a larger size, he said. Our plants are usually on the ground here in their finished pots for a full growing season. They re not a fast finishing perennial crop. We grow our plants cooler over a longer season. It s a slow way to make a living. Sundquist also increases by division, for which he maintains stock blocks. Either way, plants are two years old by the time the most vigorous species finish in #1 pots. Ferns may take five years to maturity, he said. But the wait is worth it. There s a primordial gratification from seeing well-grown, mature ferns. Sundquist uses a bark/compost/ pumice blend with supplemental nutrients. The most valuable ingredient in our soil is air; drainage is important, he said. Casa Flora, a fern producer that utilizes a lab to supply most of its starter material, is headquartered in Texas. The nearly 150 currently available ferns, both hardy and tropical, barely hint at the possibilities worldwide. Kent Kratz, vice president for research and development, runs the Casa Flora vegetative propagation lab and acquires and evaluates new plants. Ferns are underutilized and deserve more widespread use, Kratz said. I would encourage gardeners to 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 JUNE 2012 DIGGER 29

8 Outdoors, bird's nest ferns (Asplenium sp.) often attach themselves to trees but are also grown in cultivation and planted in the ground. Indoors, they're often used as house plants. The rich, red new growth on a Koidzuma's wood fern (Drypoteris koidzumiana) offers great contrast with nearby foliage. Ghost ferns (Athyrium 'Ghost') offer a very neat and tidy appearance. Their usual color is somewhere between gray and green. 30 JUNE 2012 DIGGER

9 Ferns forever look past the eight or nine ferns offered in the mass market and experiment with more unusual ferns found in finer garden centers and mail order companies. Casa Flora works to get new introductions to growers, but the process is slow. We have new plant trials that involve regional growers to find ferns that do well and have both grower and consumer interest, Kratz said. It takes several years for us to get a fern to market and another three to five years for feedback and to build sustained demand. Generally speaking, we anticipate greater than 10,000 a year eventual sales to economically justify putting a plant in the lab. We also raise ferns from spores and put some ferns in the lab that cannot be produced in another way faster. An example is Adiantum tracyi, the sterile hybrid native maidenhair from California, which can only be propagated by division or tissue culture and is extremely difficult to find. Casa Flora is doing a limited run of it and will offer it for a year or so to get it into the hands of institutions and hobbyists. If we can get a critical mass out there, it guarantees the availability of that plant and reduces pressure in the wild from collectors, Kratz said. Gaining attention and use The more our industry knows about the diversity and requirements of ferns, the more popular and less overlooked they will be, Kratz said. Learning to use ferns is an important piece in extending their use. Among ferns, there are workhorses and there are designer selections for special effects, Sundquist said. Some plants fit both objectives, but it s important to match plants to sites that meet their needs. Workhorse ferns like tassel, autumn, and sword are in the most demand. Arguably the most shade tolerant fern in commerce is our native sword fern (Polystichum munitum), Sundquist said. It s also arguably among the most sun and drought tolerant of ferns. It always amazes me that Pacific Northwest residents are so underwhelmed by sword ferns. Gardeners in other regions would kill to have such a good-looking workhorse of a fern volunteering beside their driveway. Sue Olsen concurred. For a fern that will thrive while being totally ignored, use the sword fern, she said. 32 JUNE 2012 DIGGER 31

10 Ferns forever Japanese painted fern (Athryium nipponicum var. pictum, aka 'Metallicum') boasts a stupendous silvery-purple color. It was named the Perennial Plant of the Year in 2004 by the Perennial Plant Association. Were it rare, people would be fighting to buy it. Most ferns do reasonably well in decent soil with some summer moisture and afternoon shade, Sundquist said. If blended with perennials, they work well with other shade lovers like hostas, brunneras and solomon seals for foliage value. Ferns make great midsize groundcovers too. Designers can create an impact planting using ferns on a slope or where they re viewed from above so their massed fronds are visible, Sundquist said. The effect is lush and implicitly tropical. Retailers can do a better job showing off the attributes of ferns by displaying more kinds of ferns and larger plants that show off their final form, Kratz said. Pictures seldom do justice to a non-flowering plant. Elizabeth Petersen writes for gardeners and garden businesses, coaches students and writers, and tends a one-acre garden in West Linn, Ore. She can be reached at gardenwrite@comcast.net. 32 JUNE 2012 DIGGER