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Plants that fill a similar niche:
Trillium catesbaei
Viola sororia
Viola striata

Stoneroot Collinsonia verticillata

Previously known as:

  • Collinsonia verticillata var. purpurascens
  • Hypogon verticillata
  • Micheliella verticillata
Phonetic Spelling
kol-in-SOH-nee-uh ver-ti-si-LAH-tuh
Description

Whorled horsebalm is an erect, rhizomatous, perennial, native wildflower in the mint family (Lamiaceae) found from Ohio east to the southeastern United States and is somewhat scattered. In southwestern North Carolina, it is found in rich forests ranging from moist cove forests unique to the Appalachian Mountains to dry oak forests over dense rocky areas rich in minerals and limestone. This plant grows from 6 to 18 inches tall on an unbranched stem. There are several pairs of opposite green leaves with toothed margins along the stems, but just below the flower, two pairs of leaves are arranged so closely together that they appear whorled. The flowers appear from late April to June on a terminal raceme with pinkish-white blooms. A tiny nutlet is produced from June to July. The specific epithet, verticillata, is Latin for "whorled," referring to the species leaf appearance below each flower.

Grows as a woodland plant in rich soils in partial shade.

This wildflower is the host plant for both the Owlet (Noctuidae) and the White-fringed Pyrausta (Pyrausta niveicilialis) moths, as well as the Holly blue (Celastrina argiolus) butterfly. 

Whorled horsebalm is a vulnerable species due to its limited range, as per the United States Forest Service. In North Carolina, it is ranked S2  or highly vulnerable by the North Carolina Heritage Program. 

Insects, Diseases, and Other Plant Problems:  There is limited data available.

See this plant in the following landscape :
Cultivars / Varieties:
Tags:
#showy flowers#moth caterpillar host#native perennial#endangered#bumblebee friendly#NC native#native wildflower#food source summer#food source herbage#food source nectar#food source pollen#bird friendly#mammals#partial shade tolerant#food source roots#Audubon#butterfly caterpillar host#wildflower#moth friendly
 
Cultivars / Varieties:
Tags:
#showy flowers#moth caterpillar host#native perennial#endangered#bumblebee friendly#NC native#native wildflower#food source summer#food source herbage#food source nectar#food source pollen#bird friendly#mammals#partial shade tolerant#food source roots#Audubon#butterfly caterpillar host#wildflower#moth friendly
  • Attributes:
    Genus:
    Collinsonia
    Species:
    verticillata
    Family:
    Lamiaceae
    Uses (Ethnobotany):
    Native Americans used this wildflower for medicinal purposes--digestive and respiratory problems.
    Life Cycle:
    Perennial
    Country Or Region Of Origin:
    Ohio to Southeastern United States
    Distribution:
    Native: Alabama, Georgia, Kentucky, North Carolina, Ohio, South Carolina, Tennessee, and Virginia
    Wildlife Value:
    This plant attracts birds, bumblebees, and moths.
    Play Value:
    Attractive Flowers
  • Whole Plant Traits:
    Plant Type:
    Native Plant
    Perennial
    Wildflower
    Habit/Form:
    Erect
    Maintenance:
    Low
  • Cultural Conditions:
    Light:
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    High Organic Matter
    Shallow Rocky
    Soil pH:
    Alkaline (>8.0)
    Soil Drainage:
    Good Drainage
    Moist
    NC Region:
    Mountains
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a
  • Fruit:
    Display/Harvest Time:
    Summer
    Fruit Type:
    Schizocarp
    Fruit Description:
    Fruit is a dry, nutlet and displays from June to July.
  • Flowers:
    Flower Color:
    Pink
    White
    Flower Inflorescence:
    Raceme
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Spring
    Flower Shape:
    Tubular
    Flower Size:
    < 1 inch
    Flower Description:
    The flowers are borne on a 4- to 6-inch-long raceme from late April to June. Each bloom is about 3/4 inches long and pink to whitish-pink. Flowers are in groups of 3 to 6 at each node in the inflorescence. They have 4 stamens on long filaments and are covered with glandular hairs. The tubular flower has lanceolate lobes that are two times the length of the tube. The lower lip of the corolla is fringed is as wide as it is long. Its stamens and pistils extend beyond the corolla.
  • Leaves:
    Leaf Color:
    Green
    Leaf Type:
    Simple
    Leaf Arrangement:
    Opposite
    Leaf Shape:
    Elliptical
    Ovate
    Leaf Margin:
    Serrate
    Hairs Present:
    Yes
    Leaf Length:
    3-6 inches
    Leaf Width:
    1-3 inches
    Leaf Description:
    The leaves are green, elliptical to ovate, measuring 5 to 6 inches long, and up to 3 inches wide with serrate margins. Several pairs of opposite leaves appear along the stem, but just below the inflorescence, the top 2 pairs are closely arranged, giving the appearance of a whorled pattern. The leaves are borne on short petioles, 0.5 to 1.5 inches long. Hairs are seen along the veins on the upper and lower surface.
  • Stem:
    Stem Color:
    Green
    Purple/Lavender
    Stem Is Aromatic:
    No
    Stem Cross Section:
    Square
    Stem Form:
    Straight
    Stem Description:
    The stems are green to greenish-purple and erect.
  • Landscape:
    Landscape Location:
    Woodland
    Landscape Theme:
    Native Garden
    Attracts:
    Bees
    Moths
    Small Mammals
    Songbirds
    Resistance To Challenges:
    Deer