Trientalis borealis (try-en-TAY-lis bor-ee-AL-is) is a wildflower native to the woods and forests of North America where it is found in birch and tamarack bogs, rises in sandy swamps and the sandy soil at the edges of woodlands.
It prospers in pristine areas, undisturbed by human activity, such as the southern Appalachian mountains.
This perennial herb is a member of the Primulaceae (primrose) family and is commonly called Starflower because of its pretty, singular star-shaped blooms.
Its genus name, Trientalis, is Latin and means 1/3rd of a foot.
It is a reference to the height of the plant.
The specific epithet, borealis, refers to the plants’ northern origins.
Star Flower Plant Care
Size & Growth
This delicate perennial wildflower grows to be between 2″ and 8″ inches tall.
A whorl of between five and nine leaves may be found at the apex of an erect stem.
There are sometimes a few small, pale green leaves on the plants’ stems, but for the most part, darker green leaves grow in a whorl at the plants’ apex.
These elliptical leaves may be lance-like or oblong.
They are rather thick and have relatively smooth margins.
In the middle of the summer, the plant will go dormant, and the leaves will yellow and fall.
This leaves behind the erect stalk topped by ripening seed capsules.
Starflowers usually appear singly, but occasionally two or three white blooms are found on slender, pale green, yellowish, or red stalks on the same plant.
Like the leaves, the petals of the flowers may number between five and nine.
Flowers may be between a quarter-inch and a half-inch in diameter and are seen from late in the springtime until early in the summer.
The flowers don’t produce nectar, but beneficial insects, such as Andrenid and Halictid bees, as well as Syrphid flies, pollinate the flowers and collect and feed on the pollen.
When the flowers go to seed, chipmunks feast on the seeds and gather them to hoard for winter.
The seeds are borne in capsules, each with five cells.
Seed pods not eaten by wildlife eventually burst to scatter seed, which will take root and grow in the following season.
Light & Temperature
This woodland wildflower likes to be kept in a setting providing dappled sunlight or light shade, six to eight hours daily.
Starflower is winter hardy in USDA hardiness zones 3-7. Although the plant can tolerate temperatures above 100° degrees Fahrenheit (38° C), it prefers a setting with cool summers.
Watering & Feeding
Water in a way mimicking conditions in a woodland setting.
The soil should be consistently moist but never soggy.
Water deeply, occasionally, and do so early in the morning or the evening so the water will have a chance to soak in well rather than evaporating.
A topdressing of organic compost or mulch should keep the plant nicely fed.
Soil & Transplanting
Starflower likes well-draining, acidic soil kept slightly moist as in a woodland setting.
Mix in sand or peat to ensure good drainage.
Grooming & Maintenance
These North American native plants are carefree once they have become well established.
If you do not want the plant to self-seed, deadhead the flowers before they become seed pods.
How To Propagate Trientalis Borealis
Starflower will self-seed, and it also spreads underground via rhizomes.
If you are going to grow the plant from seed, sow directly into prepared soil in autumn after the first frost and cover lightly with mulch.
The seeds need cold stratification to germinate.
Be sure to get your Trientalis rhizomes and seeds from a private collector rather than gathering them on public lands.
Trientalis Borealis Main Pest or Disease Problems
This native plant is resistant to pest and disease problems.
Poorly draining soil or excessive watering can cause root rot.
Is The Plant Considered Toxic Or Poisonous To People, Kids, Pets?
Trientalis Borealis is not listed as toxic.
Is The Plant Considered Invasive?
This plant is listed by the U.S. federal government and the states of Tennessee, Kentucky, Illinois, and Georgia as threatened or endangered.
Suggested Star Flower Plant Uses
This endangered wildflower is a wonderful choice to naturalize in a woodland native plant garden.