Sweet Fern: Like Magic and Ants

E.O Wilson, a pioneer in efforts to protect diversity, has famously described bugs as "the little things that run the world."

The late E.O. Wilson and the Northern Flicker have in common an interest in ants.

But while Wilson, in his writings, advises watching your step when navigating the crawlies in the kitchen, the Flicker greedily gobbles them up off the forest floor.

Satiated with ants, the Flicker may then seek out the tasty, dry fruits of an elegant, fern-like shrub, Comptonia peregrina.  The Mourning Dove may join in the nibbling, as will the Cedar Waxwing.

Northern Flickers are woodpeckers that can peck into tree trunks but prefer to forage on the ground. They're considered common, but their numbers have declined by 50% since the 1960s.

Sweetfern Underwing

Commonly known as Sweet Fern, the shrub also shelters small mammals and serves as a larval host to nearly 50 butterfly and moth caterpillars, including the Sweetfern Underwing, Apple Sphinx and Gray Hairstreak.

What’s In a Name?

Sweet Fern is not a fern; it’s a shrub so-named because of its long, luscious and lacy, medium-green leaves that resemble the fronds on a fern.

When crushed these leaves emit an aroma described variously as “herbal,” “sweet” and “citrusy,” and like fresh pine needles.

The fern-like leaves on Sweet Fern

Like Magic

Sweet Fern grows naturally in dry, open areas like pine barrens.  It also likes poor soil, primarily because of its magical ability to “make” its own nitrogen.  

Essentially Sweet Fern pulls the nitrogen from the air and, with help from bacteria, transfers it into the soil in a form beneficial to it and other plants.  Sweet Fern’s cousin, Northern Bayberry, and many of the legumes also are “nitrogen-fixers.”

A growing colony of Sweet Fern, adding luscious greenery, quiet and softness to the garden.

Fall leaves on Sweet Fern. Photo: Wikimedia Commons

Understated Blooms

Sweet Fern works beautifully in the home landscape, adding elegance, texture and greenery to the garden. 

It is not necessarily a common sight in most gardens, possibly because its leaves are deciduous (although turning a stunning reddish-orange in the fall) and its blooms could be favorably described as understated.

In New England, these leafless flowers usually appear in early summer, with males forming brown catkins and females looking red and roundish.  Usually both males and females are found on the same bush.  

Female flowers on Sweet Fern

As a Ground Cover

Another drawback may be its abhorrence to being transplanted, especially after the big machines cut its roots out of the soil.  A young specimen grown in a container and with all of its roots intact may weather the move better. 😃

While Sweet Fern stays a reasonable 2 to 5 feet tall, it’s a slow grower but eventually will spread nicely by sending out horizontal, underground “runners,” or stems, that will form new, independent bushes. Try it around the home’s foundation, as a low hedge or as a ground cover for a larger area.

Dry or Moist

Sweet Fern has deep roots, making it a clear choice for soil stabilization, and it’s ideal under power lines – basically anywhere the soil is medium to dry and there’s a lot of sun.  It likes sand but not clay.    

Bearberry, New Jersey Tea, Black Huckleberry and Little Bluestem make nice companions.  

Because of its root structure, Sweet Fern also does well along pond and stream banks and even at the edges of a rain garden.  In these wetter spots, it partners well with Wool Grass, Swamp Rose Mallow and Marsh Marigold.

Resistance

Rabbits may hide under the branches, and deer may nibble the branches, but by and large Sweet Fern is resistant to damage from these critters. 

Fun fact 😃: Sweet Fern also repels ants 🐜, which don’t like the aromatic foliage.  It’s also a mosquito repellant, according to the Friends of Conservation in Salem, Mass.  Rub the leaves on your skin, they say, and it will keep the bugs away–like magic 🧙🏻‍♀️.

---

About the author

Jennifer Anderson owns Tree Talk Natives, a native tree and plant nursery along Massachusetts' South Shore. A former news reporter, she loves to write and talk about native plants. Jennifer also gives garden consultations and presentations on native plants. She can be reached at jennifer@treetalknatives.com.

---

Sources:

• Barlow, V. Sweetfern, Comptonia peregrina Northern Woodlands. Spring 2009

• Comptonia peregrina. Fire Effects Information System. USDA

• Comptonia peregrina, Sweet Fern.  Native Plant Trust

• Dwyer, M. Comptonia peregrina (Sweet Fern). Nursery Management. April 5, 2025

• Northern Flicker. All About Birds. Cornell Lab.

• Sweet Fern (Comptonia peregrina). Mt Cuba Center

• Sweet Fern: Keep Bugs Away and Berries Fresh. Sharon Friends of Conservation  

• Wilson, E.O. Tales from the Ant World. August 25, 2020. Liveright Publishing Corporation