Sword fern, polystichum munitum: It carpets the lush forests of the Pacific Northwest; it is one of the crown jewels of our native plant kingdom. While it is easy to grow and ubiquitous in our landscapes, natural and human made, it is beloved, giving the lie to the notion that familiarity breeds contempt.
In their book “The Plant Lover’s Guide to Ferns,” Richie Steffen and Sue Olsen say: “Were this species rare, there would be a tremendous demand (and price) for it.” In his iconic guide “Gardening with Native Plants of the Pacific Northwest,” Arthur Kruckeberg calls it “majestic.” For me, sword ferns are something of a love affair.
In 1985, I made my first to trip to the English Cotswolds to meet with Rosemary Verey at her famous garden at Barnesly House. The great maven of horticulture and author of innumerable books met me, thrusting out her hand and saying, “Oh so happy to meet you. I long to visit your part of the world and see those incredible sweeps of polystichum munitum.” Rosemary did get here a number of times after that, and the sight of those sweeps of sword fern did not disappoint the woman who helped the Prince of Wales landscape Highgrove and Elton John surround his country estate with a proper English garden. She knew a great plant when she saw one.
Japanese garden designers love to tuck this evergreen beauty next to large rocks … and they must be large. In bright, indirect light, this plant matures to a height of 3 to 5 feet with an equal spread, producing 50 to 100 new fronds annually. The foliage is blade shaped, and while the fronds are stiff and somewhat coarse textured, the overall effect is one of a cluster of giant emerald feathers.
In 1991 when I began my garden on 10 acres at the foot of the Cascades in the Upper Skagit Valley, my goal was that, once established, it would pretty much take care of itself. The garden was to have the look of a quasi-exotic forest floor so that the untrained eye would not know where nature left off and where I had started. Conifers, broad-leafed evergreens and deciduous shrubs chosen for bloom, autumn color and winter form were spotted around the garden. Something was needed to connect it all. Sword ferns came to the rescue. To assure that weeds, most annoyingly blackberries and horsetail, did not invade the beds, I cleaned them (digging everything out by the roots), worked the rich acid soil, put the non-native plants in, then filled in the rest with sword ferns. Once all plants were in, I soaked the soil thoroughly and deeply and scattered a 16-16-16 fertilizer over the ground. Then, I covered that with 10-page-thick rectangles of newspaper, overlapping the papers so that no bare ground was exposed. I soaked the newspaper and then covered that with straw and watered again. The plants, all of them, surged into growth. The newspaper and straw retarded all weeds, and in three years all the plants had grown into one another in rhapsodic harmony, rising from a luxurious ground cover of sword ferns.
The challenge was where to get all the ferns I needed. I did not want to rob my woods of these gems, and, while Northwest native nurseries sell them, I needed a king’s ransom in plants. So I traveled backroads and there, where plots of public land had been clear cut, I found sword ferns that had been fried when their canopy of shade had been taken. I dug them by the car trunk load, took them home and submerged the plants in a tub of water over night. Next morning I cut back all the fronds and planted the rooted crowns. The following spring, vigorous new fronds unfolded. The fern carpet was born.
Surprisingly, sword ferns will grow in full sun. The fronds will be stiffer, smaller and more upright, but they are equally effective in adding “wings to the garden,” as writer and horticulturist George Schenk so poetically put it.
Each year the old fronds brown and, in time, shrivel. To keep the plants looking spiffy, a fastidious gardener will cut off the previous year’s fronds just as the new ones are about to emerge. This is the month to do that.
Look down into the crown of the plant. You’ll see the new, infant leaves curled up in a handsome mound. Cut the old fronds away. The garden will look bare for a week or two, but then you’ll have the joy of watching the new fronds poke out, stretch up and unfurl: a perfect heralding of spring! Spread out uniformly under and between the ferns and mixed shrubs, the cut fronds make a great mulch, retarding weeds, holding in moisture and discouraging slugs.
That bare period from grooming to new fronds can be abated. Gertrude Jekyll, the British garden designer, active in both the late 19th and the early 20th centuries, planted daffodil bulbs around her sword ferns. She cut back the old fronds just as the daffodils were popping up. They bloomed surrounding the fern crowns, then, as the daffodil leaves began looking ratty but were still needed to fortify the bulbs below, the new fronds emerged to cover them. Other than grooming, once planted in our rich acid soil and open to natural irrigation, there is little to do to keep this robust native in its natural state of splendor.
Coming back to the Pacific Northwest, no matter the palms, orchids, cacti or autumn-fired hardwoods I’ve seen, I always marvel at the beauty of our incomparable natives, sword fern prime among them. I feel like Dorothy returned to Kansas: There’s no place like home. Long ago, on the Olympic Peninsula, I rounded a bend in a trail through the low woodlands, not far from the Pacific. There, covering an acre or more, I found myself in the midst of a sea of sword ferns cut out of a grove of conifers and alder. Through the ferns, the occasional clump of vine maple stretched up, and in the middle of it all stood a board and batten cottage, roofed in shakes, the cedar siding weathered a handsome tarnished silver. It was as beautiful as any garden and house I’ve ever seen.
At a certain age (I’m there), one begins to think what comes next as the light at the end of the tunnel of life grows brighter. I’ve hatched many scenarios, but one is reoccurring. I hope I can tap the heels of my Ruby Hiking Boots together three times and come-to in that sea of sword ferns, looking at that house, knowing that inside all my family and all our dogs will be waiting for me to come in and sit down for dinner.