Ferns
Wild Seed Project: Returning native plants to the Maine landscape
by Heather McCargo • June 4, 2018

Ferns are ancient plants whose ancestors first appeared on Earth over 300 million years ago. Members of a division of primitive plants called Pteridophytes, ferns are one of the earth’s oldest plant groups and dominated the land before the rise of flowering plants. During the age of the dinosaurs, ferns and other primitive plants such as club mosses and horsetails reached magnificent proportions, many over one hundred feet tall. This period of the Earth’s history had a global climate of warm temperatures and high humidity, ideal conditions for ferns to flourish.

How Ferns Reproduce

Ferns are dependent on moisture for their sexual reproduction. Their primitive method of propagation evolved before flowering plants and involves two distinct phases in their life cycle: the mature fern that we all know and recognize; and the reproductive phase when they are just small flat plants that look like leafy liverworts. Sometime during the growing season, a mature fern releases spores, which are the plant’s sexually reproductive cells. With adequate moisture and light, these spores begin to grow into small flat plants called prothallia, the second phase in the life cycle. Male and female sex organs develop on the prothallia. If fertilization occurs, the egg cell grows into a young fern (sporophyte), and the life cycle of a new fern begins again, often taking several years to reach maturity.

In nature, fern spores germinate in moss, rotting logs, or damp exposed soil in shady locations (such as by a stream). Moist, porous rock such as limestone ledges are also ideal fern habitat. A patient person may be successful laying fern fronds with ripe spores onto a rotting log, bed of moss or moist limestone, but it may take a few years before you will know if you have been successful. Fern spores can be propagated indoors in a bright windowsill out of direct sunlight or under lights. (See references at the end of this post for details on growing ferns from spores).

It was a global climatic shift to a dryer planet late in the Cretaceous period (as the dinosaurs were waning) that allowed the flowering plants’ rise to dominance. Flowering plants, with their amazing new trick of sexual reproduction via flowers and seeds that are able to disperse and ride out the dry or cold spells, shifted the world’s dominant vegetation away from ferns.

Ferns in the garden

Ferns make excellent landscape and garden plants, especially in shady or moist environments. Their beautiful foliage is striking all season, beginning when their first leaves unfurl in the spring (like a fiddlehead), to their intricate foliage in many different shades of green to their fall colors of yellows, golds and browns. Though they are not pollinated by insects, their foliage still provides food for many butterflies and moths during their caterpillar stage. Despite the delicate look of ferns, many of them are very hardy, thriving in deep shade, damp soggy soil and even dry and acidic locations in full sun! Ferns even look great as potted plants. (see photo of maidenhair fern in pot)

Below are a dozen species of ferns native to the northeast United States that make great garden or landscape plants. When purchasing ferns, please make sure that they have been propagated in a nursery and not dug from the wild, a still too common practice that is damaging to wild plant communities (read a previous blog post to learn more).

A Dozen Ferns to Grow in Your Landscape

As woodland plants, ferns thrive in soil with a mulch layer of leaf mold or aged hardwood bark. Mix with other shade-loving native perennials, trees and shrubs to create a dynamic landscape full of interest for people and other wildlife. Ferns also look great in a large pot (read an earlier blog post, “In the Shade,” to learn more).

Maidenhair FernMaidenhair fern
Adiantum pedatum
Blue-green foliage with striking black stems growing 18” tall and forming clumps 3’ wide. Mixes well with other woodland wildflowers such as wild ginger and bloodroot. Full to partial shade, moist to wet fertile soil. Native to deciduous woodlands and streamside with limestone bedrock.

Lady FernLady fern
Athryium felix-femina v. angustum
Delicate green fronds unfurl to make vase shaped clumps 3 ‘tall by 18” wide. Distinctive dark specks on their lower stem make them easy to recognize. Stems can be green or red. The creeping root systems are good for stabilizing slopes and look dramatic mixed with Solomon’s seal or cranes-bill geranium. Tolerant of sun if soil is consistently moist, otherwise plant in part to full shade. Native to deciduous forests throughout the region.

Hay ScentedHayscented fern
Dennstaedtia punctiloba
Bright yellow green fronds thrive in dry, infertile and highly acidic soils creeping aggressively to create a ground cover 18 inches tall and capable of carpeting large areas. This is an extremely tough plant that will dominate unless mixed with other strong plants, such as large-leaved wood aster or Canada anemone, making a lovely tapestry of leaf textures and blooms, and a dynamic and easy ground cover for large areas under shrubs and trees. Rocky deciduous or coniferous woods and clearings in sun or shade. Very drought tolerant once established.

Marginal FernMarginal wood fern
Dryopteris marginalis
Distinctive upright vase-shaped fern that is very adaptable in the garden and landscape. A mature plant is 18 inches tall and wide and stays put to make a nice speciman. Foliage is evergreen but after a long snowy winter fronts will be flattened in the landscape. A widely distributed fern of deciduous forests.

Northern Oak FernNorthern Oak Fern
Gymnocarpium dryopteris
A low ground cover fern with delicate bright green foliage 8 inches tall. Fronds are distinctly divided into three parts, making it easy to identify. Perfect for cool, moist acidic soils, such as Downeast and the cool mountain areas of our region, often found growing with bunchberry and wood asters, both excellent garden companions. Native to cool, coniferous woodlands. See our detailed profile.

Ostrich FernOstrich fern
Matteuccia strutheiopteris
This is the edible fiddlehead fern beloved by wild food enthusiasts. Medium green vase-shaped fronds are 3-4 feet tall, and over time spread to cover large areas making a dramatic lush groundcover. Plant if you have a large shady location, but not a small garden. Once established, early spring harvests right out your back door make this the shady perennial vegetable ideal for home landscapes and organic farms. Moist to wet soils, tolerant of dry soil in summer.

Sensitive FernSensitive fern
Onoclea sensibilis
This low-growing ground cover fern has distinctive fronds that lack the feathery appearance of most ferns. In early spring the foliage has a reddish cast that turns to medium green. Moist to average soil, 12” high and spreads to form large patches. Looks great with other tough wetland perennials such as Chelone and cinnamon fern. Wet to medium moisture woods.

Cinnamon FernCinnamon fern
Osmunda connamomea
Large, bright green vase shaped fern, 3 feet tall and wide that make dramatic specimens in the garden. The unfurling fiddleheads are coated in tannish fur and later in the spring the cinnamon colored fertile fronds appear in the center, making this species easy to identify in the wild. Moist to wet soils in part to full shade. Native to deciduous woods and wetlands.

Royal FernRoyal fern
Osmunda regalis v. spectabilis
In the spring the fronds unfurl with a pinkish blush and once unfurled become a blue-green upright vase- shaped plant. Foliage reaches 3 feet tall and stays in tidy clumps. Cardinal flower makes a dramatic companion for shady moist sites. Wet to medium moist soil, often found growing on the edge of streams and wetlands.

New York FernNew York Fern
Parathelypteris noveboracensis
Small, delicate bright green fronds 12 inches tall make small ground covering patches that mix well with other perennial wildflowers such as foam flower, wood phlox and bunchberry. It has a similar look to hayscented fern but is much less aggressive so appropriate for smaller spaces and mixing with other species. Native to deciduous and coniferous woods and edges in moist or dry soil.

Rock PolypodyRock polypody
Polypodium virginianum
A charming low creeping plant of rocky ledges. Evergreen fronds are 8 inches tall. Perfect for rock walls and ledged slopes in acidic soils. Found in the wild growing on the litter that accumulates on large rocky boulders and cliffs in moist deciduous and coniferous forest.

Christmas FernChristmas Fern
Polystichum acrostichoides
Distinctive dark green clumps of upright evergreen leaves 18” tall by 18” wide. Beautiful mixed with other ferns and native perennials. A very handsome garden fern with a long season of interest. Moist to summer dry soil. See our detailed profile.

 

More information on growing and propagating ferns