Trillium: Icon of the Wildflower Garden

Jeanne Frett

Research Horticulturist

This month’s edition of Nature’s Landscape is produced by Jeanne Frett, Mt. Cuba Center’s Research Horticulturist.  With nearly two decades of experience growing, propagating and writing about trilliums, Jeanne is uniquely qualified to share her perspective on this very special group of plants.  We hope you enjoy this window into a fascinating group of wildflowers, beloved by many and grown by few. –Rick J. Lewandowski

Looking back on my early days at Mt. Cuba Center more than 18 years ago I must admit to a wave of panic with the approach of mid-April as we scheduled spring woodland wildflower garden tours. Would the still dormant wildflowers make their appearance above ground in time for guests’ arrival?  Was the transformation from a grey monotone landscape of winter to the profusion of colorful spring wildflowers and foliage possible in just a few weeks?

Spring’s Greatest Treasures

Fortunately, with careful observation and experience I discovered clues in the garden to the arrival of spring, in particular, the joyful appearance of one of our most beloved wildflowers, trilliums. Trilliums first entered the Mt. Cuba Center gardens during the 1960s, coming from wildflower nurseries, the generosity of friends, and from propagation research.  Many trillium species found naturally in the forests of the eastern U.S. were planted and began to thrive in the garden.  Interestingly, though, only one trillium can be found growing naturally in the woodlands at Mt. Cuba Center, nodding trillium (Trillium cernuum), which grows in the cool and moist soils along the Red Clay Creek.

Trilliums are so recognizable among the wide array of spring wildflowers because they possess three leaves and a large, solitary 3-petalled flower sitting directly on the foliage or on a short stem immediately above it.  Mention the word “trillium” and most knowledgeable gardeners envision the great white trillium or large-flowered wake robin (Trillium grandiflorum).  This trillium provides a magnificent spectacle, forming vast pure white sheets of flowers on the woodland floor from Maine southward through the Appalachian Mountains to Georgia from mid-April to early May.

But the great white trillium is not the first to appear in the garden each spring, nor is trillium limited to white flowered plants with green leaves. Indeed, there are more than 30 species of trilliums with striking variation found throughout the eastern and southeastern U.S.  Each of these species possesses qualities and adaptability that give them special charm.  Below are a few examples of species that provides a window into the diversity of trilliums.

Charming Diversity

The earliest trillium to flower in the garden is the dwarf or snow trillium (Trillium nivale), aptly named because it resembles a miniature great white trillium.  Its foliage and flowers remain unaffected by late winter snowfalls. This diminutive gem can flower as early as mid-March on short stems only 3” to 6” tall.

Trillium cuneatum

Trillium decumbens

During the first two weeks in April, trailing trillium (Trillium decumbens) and the large toadshade (Trillium cuneatum) are garden highlights.  Both have reddish-maroon flowers perched directly on mottled (spotted) green foliage. Trailing trillium foliage hugs the ground while large toadshade has 6” to 18” tall stems topped by fruity, pleasantly scented flowers.

Trillium luteum and Phlox divaricata.

These trilliums make great companions with other early season wildflowers including Virginia bluebells (Mertensia virginica), celandine poppy (Stylophorum diphyllum), trout-lily (Erythronium americanum), rue-anemone (Thalictrum thalictroides), bloodroot (Sanguinaria canadensis), Dutchman’s breeches (Dicentra cucullaria), and blue phlox (Phlox divaricata) just to mention a few.

Because of their early spring appearance and unique floral or foliar characteristics, trilliums have received some very colorful common names in American folklore.  Names include toadshade, sweet Betsy, whippoorwill flower, stinking Benjamin, wet dog, sweet Beth, wake-robin, painted lady, bloody butcher, and elk heart among others.

Trillium grandiflorum

Trillium stamineum

Trillium luteum

Several trilliums flower in mid- to late April with very different characteristics, including the great white trillium (Trillium grandiflorum), yellow trillium (Trillium luteum), and twisted trillium (Trillium stamineum). Yellow trillium has extremely attractive upright, flame-shaped flowers with yellow petals and a lemony fragrance.  This species often has leaves that are mottled or spotted in various shades of green.  Gardeners at Mt. Cuba Center combine yellow trilliums with maidenhair fern (Adiantum pedatum), wild blue phlox (Phlox divaricata), and foamflower (Tiarella cordifolia) to create a multi-layered, complex textured, and colorful groundcover ensemble.

The twisted trillium, as you might guess by its name, is quite unique.  Its dark purplish-red, twisted petals are held horizontally and curiously arranged so that they resemble the propeller blades of an airplane.  This unusual feature makes twisted trillium a delightful oddity in the spring garden.

Trillium vaseyi

From early to mid-May, the majority of wildflowers are in full glory including one of the last trilliums to flower, Vasey’s trillium (Trillium vaseyi). This species might easily be missed because its large, nodding, crimson-maroon flowers are hidden beneath wide spreading foliage.  I’m told that some people have been lucky enough to detect the faint odor of roses from the flowers. Visiting Mt. Cuba Center at this time of year is likely to result in an encounter with other woodland wildflower treasures that grow near or with this trillium such as the exquisite southern lady’s slipper orchid (Cypripedium kentuckiense), large yellow lady’s slipper orchid (Cypripedium parviflorum var. pubescens), wild columbine (Aquilegia canadensis), blue cohosh (Caulophyllum thalictroides) and many others.

The Reward Takes Time and Ethics

The propagation of trilliums from seed to flowering is typically a slow process, requiring 5 to 7 years before plants reach flowering size.  At Mt. Cuba Center we routinely collect and germinate seeds each year.  In any given year thousands of seedlings, in all stages of maturity, are growing in our propagation facilities.

For those of you without the inclination or patience to wait this long, the only alternative is to purchase plants.  But this is not as easy a task as it might seem.  Trilliums can be hard to find commercially.  When you can find them for sale, you need to be sure they have been grown responsibly.  What does this mean?  Sadly, the unethical and irresponsible commercial harvesting of trilliums from forests is still practiced. This short-sighted practice reduces native plant populations and destroys valuable habitat; furthermore, few of these plants survive to make it to the garden. 

You should make every effort to purchase only “nursery propagated and grown” plants produced by reputable nurseries.  However, be careful; the term “nursery grown” is a similar, yet, deceptive description sometimes used by unscrupulous dealers to fool people.  This term refers to plants that were harvested, or wild-collected, in nature and grown for a short time in a nursery before being sold—again, an unethical, harmful practice. In the end, to purchase trillium responsibly, ONLY buy from reputable professionals. 

Though trilliums are still uncommon in garden centers, you can enjoy their beauty in nature at many State and National Parks throughout the eastern U.S. where you can observe and photograph them.  Another option is to make a much shorter journey to the diverse woodland gardens of Mt. Cuba Center where thousands of trilliums from throughout the eastern U.S. grow together with many beautiful wildflower companions.  Regardless, I think you will be charmed by their beauty and inspired to preserve them.