Wonderful Wood Ferns

Reading fern descriptions can be as tedious as wading through the Smiths in a phone book. Frond for frond, most people think they all look the same. Not wood ferns (Dryopteris spp.). They are aristocrats in stature and form—the Smyths among the Smiths. Their bold lustrous fronds, held in elegant ascending arches, offer a longer season of interest than the familiar maidenhair and Japanese painted ferns that swoon in hot dry weather and fade with the first frost.

The genus Dryopteris contains approximately 250 species worldwide, with the majority found in temperate Asian forests. Wood ferns produce exquisite upright to arching fronds from stout rhizomes with dense fibrous roots. The fronds, deciduous or evergreen, arise in a circle around an upright growing point, or caudex. Sizeable crowns develop with time. The shape of individual fronds varies from stoutly triangular to exceptionally elongated, with pinnae that taper toward their tips. Many are remarkably frost tolerant, while others topple with the advent of cold weather.

The name wood fern refers to the plant’s preferred habitat: moist forests, often atop decaying logs. The alternate names, shield fern and buckler fern, arise from the shield-shaped cover over their spore-producing sori. Dryopteris hybridize readily, and the many naturally occurring hybrids are taxonomically challenging but eminently gardenworthy.

In The Garden

Most wood ferns share a predilection for moist shaded places in humus-rich, moderately acidic soil. A few have more specialized requirements, demanding strongly acidic or neutral soil, but they are rare exceptions. Many species are remarkably drought tolerant once well established, but best growth is achieved with consistent moisture. Deciduous and semi-evergreen species need bright light to develop fully, and they appreciate some direct sun. Evergreen species are remarkably shade tolerant. Shade, in fact, is mandatory in warmer zones. Plants get large when mature, so leave ample room when first planting them. To propagate, divide offsets from the main crown in spring.

Summer’s woodland wardrobe is by and large a subtle interplay of form and texture. By adding one or more of these distinctive ferns to your garden, you can punch up the dramatic impact of a shaded spot, draw visitors into a cool oasis, and still have something to show when autumn’s chill settles in. Wood ferns are striking accents. Position them next to stumps, logs or tree trunks for dramatic effect. The fancy-leaved selections are singular additions to wildflower gardens, especially among low groundcovers, where their unique form and texture stand out like works of art. En masse they create elegant carpets under flowering shrubs or along a foundation.

A Dozen Dryopteris

The beaded wood fern (Dryopteris bissetiana) is delicate and exceptional, with lustrous, deep green, one- to two-foot triangular fronds, whose constricted pinnae make them appear beaded. Silvery hairs cover the undersides of the evergreen fronds. New fronds of this Asian native emerge late among the rings of last year’s, which are still crisp and lovely. This fern is hardy in USDA Zones 5 to 8, as are all of the following (unless otherwise noted).

Champion’s wood fern (D. championii) has two-foot, broad, lacquered bipinnate evergreen fronds that hold up well in frost and snow. New apple green fronds emerge late, covered in silken hairs. This Asian native is a good choice for areas with late frosts that can damage fresh growth.

Thick-stemmed wood fern (D. crassorhizoma) is a colossus among ferns. Less heat-sensitive than the equally dramatic D. wallichiana, this charmer settles quickly. The ultimate size is three-and-a-half feet or more in height and spread, with a large vase-shaped crown of pinnate-pinnatifid fronds from a huge rhizome. This fern is native to northeastern Asia.

Formosan wood fern (D. formosana) has elongated triangular blades up to two feet that sit well above the ground on long scaly stipes. The semi-evergreen bipinnate fronds are distinctive, with an elongated triangular form and attenuated dagger-shaped basal pinnae. This native of Japan and Taiwan is hardy in Zones 6 to 9.

The flaming red-orange fronds of sunset fern (D. lepidopoda) emerge from the center of last season’s growth. Broadly lance-shaped bipinnate fronds appear freshly lacquered. As fronds age, they fade to green and ultimately form a broad clump two feet tall and wide. Sunset fern is native to the Himalayas, western China, and Taiwan.

The Mexican male fern (D. pseudo-filix-mas) produces huge, narrow pinnate-pinnatifid to bipinnate fronds with fingerlike pinnae in open lines along the rachis. The fronds emerge from a stout rhizome in a tight vase. Plants reach five feet in evenly moist rich soil where summers are cool. In warmer zones, three feet is characteristic.

Dryopteris purpurella is a gorgeous, regrettably scarce Japanese fern with large triangular evergreen bipinnate-pinnatifid fronds that emerge brilliant copper red in spring. Similar to autumn fern, but larger, this exquisite speciesgrows three- to three-and-a-half feet tall and wide.

Unique in every way, Siebold’s wood fern (D. sieboldii) has leathery once pinnate fronds that resemble a brake fern (Pteris spp.) more than a wood fern. Plants emerge late in the season and make few fronds each year. This Asian native is slow growing. It increases at a snail’s pace if the foliage is consistently damaged from season to season. It is hardy in Zones 6 to 10, but the fronds burn easily below 20°F.

The ladderlike fronds of Tokyo wood fern (D. tokyoensis) are distinctive and elegant. They create a strong vertical accent perfect for adding height to low planting or for accenting tree trunks or mossy rocks. This moderately fast grower reaches three feet tall.

Crested uniform wood fern (D. uniformis ‘Cristata’) is the most widely available form of this gorgeous evergreen Asian fern. Gracefully ascending, two- to two-and-a-half foot bi-pinnate fronds have narrow crested pinnae borne on striking black scaly rachis.

Wallich’s wood fern (D. wallichiana) is a lovely vase-shaped plant with tropical-looking semi-evergreen pinnate-pinnatifid fronds. The tightly arranged glossy pinnae fill out gracefully arching fronds that grow two to five feet tall. This high mountain native from both Europe and America is intolerant of excessive summer heat. Southern gardeners should substitute D. crassorhizoma.

Obvious Beauty

I used to think it took a sophisticated gardener to appreciate the subtle beauty of ferns. But this bevy of fronds is sure to appeal to anyone with an eye for grace or a flair for the dramatic. The first fiddleheads of spring bring you a world of green as diverse and intricate as any meticulously orchestrated border scheme.