These Northwest favorites actually can grow just about anywhere
The Pacific Northwest is fern country. Thanks to a cool, moist climate, magnificent stands of sword fern (Polystichum munitum) grow in great sweeps on forest floors and form delicate tufts of green lace on rocky cliffs. In cities, wind-driven fern spores land and take root on bits of debris caught along downspouts, making feathery little clumps that march up the sides of old brick buildings. Ferns fill gardens and bouquets. Their decorative leaves are sometimes pressed into concrete steppingstones, and, sometimes, into our memories.
Once, when my son was a toddler, we walked through an alder forest on the Olympic Peninsula. A thick carpet of sword ferns covered the ground. As the fronds bobbed gently in the wind, my son stretched out his arm, pointed to them, and shouted, “Butterflies!” The little guy was in good company. Renowned Northwest garden writer George Schenk once called ferns “the wings of the garden.”
The fern family is as diverse as the plants are lush and beautiful. Many of them grow well throughout the West (except in the low desert) if you give them shady locations; rich, loose, acid soil; and plenty of water.
In the coldest regions of the West (Sunset climate zones 1–3), many ferns can survive if they’re planted close to a house foundation, with some winter protection such as a thick mulch of leaves or straw over the crown. In hot, dry climates, ferns grow best in pots placed in shaded courtyards or patios. In coastal Southern California, tropical and subtropical ferns can easily duplicate the effects of a Northwest forest planting.
How can you use ferns in the landscape? Northwest gardens and woods offer great design lessons. Ferns are especially handsome as accents among swaths of lower-growing plants such as sweet woodruff or oxalis (O. hirta or O. oregana) or growing beside ponds. Mossy rocks, especially when wet, make beautiful foils for ferns. Mixtures of green can be as vivid in their own right as any bed of gladiolas or zinnias.
Best bets: 10 ferns we can’t resist
Adiatum aleuticum (five-finger fern, Western maidenhair fern). Zones 1–9, 14–21. Deciduous. Thin, papery, green fronds have large leaflets in a fan shape atop glistening black stems. Will take some early-morning or late-afternoon sun. To 2 feet tall.
Athyrium filix-femina (lady fern). Zones 1–9, 14–21. Deciduous. Feathery, lance-shaped fronds are soft yellow-green. Easy to grow. Prefers moist shade. To 3–5 feet tall.
Athyrium nipponicum ‘Pictum’ (Japanese painted fern). Zones 4–9, 14–24. Deciduous. Plant arches over, giving it a sprawling look. Glowing burgundy stems have fronds that are silvery at the center, gray-green around the edges. Needs moist soil, even in winter when dormant. To 1–2 feet tall.
Blechnum spicant (deer fern). Zones 1–9, 14–17. Evergreen sterile fronds are narrow, dark green, and leathery, with closely set leaflets. Deciduous fertile fronds are stiff and upright, with widely spaced leaflets. To 1–2 feet tall.
Dryopteris erythrosora (autumn fern). Zones 4–9, 14–24. Evergreen. Firm fronds open from coppery pink fiddleheads―golden green in youth, developing to rich, dark, glossy green. Prefers some high, filtered light or early-morning or late-afternoon sun to get intense coloration. To 2–3 feet tall.
Dryopteris ‘Robust’. Zones 1–9, 14–24. Semi-evergreen; hangs onto its fronds well into winter in mild climates. Bold foliage is deeply divided and ruffly-looking. Fronds unfold apple green, getting darker with age in shade, yellowish green in sun. With good water this plant will take full sun. Stands up to a wide variety of soils. Fast-growing and easy. To 3–5 feet tall.
Osmunda regalis ‘Purpurascens’ (European royal fern). All zones. Deciduous. New growth emerges deep purple-red. Stems maintain red color, but fronds age to pea green. Leaflets are reminiscent of locust leaves. This tough plant withstands full sun and wind in soggy conditions. To 6 feet or taller.
Polystichum munitum (sword fern). Zones 4–9, 14–24. Evergreen. Tall, stiff, slightly arching, spear-shaped fronds are dark green in shade, lighter green in sun. Happiest in moist soil with some shade but will tolerate dry conditions and full sun. A Northwest signature plant, it is the most common fern in the region. To 3–4 feet tall.
Polystichum polyblepharum (tassel fern). Zones 4–9, 14–24. Evergreen. Dense and lacy dark green fronds have a varnished look. Likes evenly moist soil. Will not take full sun. To 2 feet tall.
Polystichum setiferum (soft-shield fern). Zones 4–9, 14–24. Evergreen. Slightly arching fronds have a soft, plumelike texture. The many cultivated varieties, each with its own characteristics, include dwarf P.s. ‘Congestum cristatum’ and lacy P.s. ‘Divisilobum’―also called Alaska fern (a misnomer, since it is not native to Alaska). Soft-shield ferns are almost as sun- and drought-tolerant as sword ferns, but for best results, plant them where they won’t get midday sun and give them even moisture. To 2 feet tall.
Where to buy ferns
These six Northwest nurseries sell a wide selection of ferns by mail.
Collector’s Nursery, 16804 N.E. 102nd Ave., Battle Ground, WA 98604; (360) 574-3832. Catalog $2. Open by appointment only.
Fancy Fronds Nursery, Box 1090, Gold Bar, WA 98251; (360) 793-1472. Catalog $2. Open by appointment only.
Foliage Gardens, 2003 128th Ave. S.E., Bellevue, WA 98005; (425) 747-2998. Catalog $2. Open by appointment only.
Robyn’s Nest Nursery, 7802 N.E. 63rd St., Vancouver, WA 98662; (360) 256-7399. Catalog $2.
Russell Graham, 4030 Eagle Crest Rd. N.W., Salem, OR 97304; (503) 362-1135. Catalog $2.
Siskiyou Rare Plant Nursery, 2825 Cummings Rd., Medford, OR 97501. Catalog $3.