common blue violet

Great Plains

Midwest

FAC - Facultative

Northcentral & Northeast

FAC - Facultative

Native

Common and widespread

Moist to wet. Woods, meadows.

April to June

Violet to white

3″ to 8″

This is a common and widespread stemless blue violet. It is an erect, perennial forb that rises from an underground stem (rhizome). It can be 3″ to 12″ tall but in Minnesota it is usually no more than 8″ in height. The rhizome is short, stout, and horizontal or oblique. It sometimes branches to form colonies. It does not produce above-ground creeping runners (stolons).

There is no central stem. A rosette of basal leaves rise directly from the rhizome on up to 6″ long leaf stalks (petioles). The petioles are strongly ascending, hairy, and have a single groove on the upper (dorsal) side. At the base of each petiole is a pair of leaf-like appendages (stipules). The stipules are green, less than ⅝″ long, and separate completely from the petiole. Leaf blades are held at an angle to the petiole. They are broadly egg-shaped to kidney-shaped, rounded or angled at the tip, and heart-shaped at the base. Most are as wide as they are long and most are broadly angled at the tip. They are unlobed except for the heart-shaped base. The sinus at the base of the blade is relatively broad and the lobes do not touch. Summer leaves are 2⅜″ to 5⅛″ wide. The hairiness of the leaves varies between populations, from nearly hairless to conspicuously covered with spreading hairs. The upper surface may be hairy or hairless. The lower surface is usually hairy at least at the base. The margins are toothed with rounded to slightly sharp teeth.

One to several leafless flower stalks (scapes) rise from the rootstock at the middle of the rosette. The scape is erect, leafless, usually hairy, and topped with a solitary flower. It is abruptly curved downward near the top. It is usually about 4″ long, shorter than the petioles, and the flowers are usually overtopped by the leaves.

Two types of flowers are produced: open, cross-pollinated (chasmogamous) flowers are produced in the spring; and closed, self-fertilizing (cleistogamous) flowers are produced in the summer.

Cross-pollinated flowers are ¾″ to 13 ⁄16″ long and wide. There are 5 sepals, 5 petals, 5 stamens, and 1 style. The sepals are green and shorter than the petals. The petals are usually medium violet with a dark violet ring near the base and white at the base. They are sometimes completely white. The two upper petals are erect or bent backward. The two lateral petals are spreading, white at the base, and have a tuft of white hairs (beard) near the throat. The lower petal is as long as the lateral petals but is not bearded. It has conspicuous, dark purple veins near the throat and a hooked, rounded spur at the base. The 5 stamens are orange and have very short filaments. They do not protrude from the throat of the corolla and are concealed by the beards of the petals. The flowers are not fragrant.

Self-pollinating flowers are inconspicuous. They occur on shorter scapes that may be arched or lie flat on the ground.

The fruit is an egg-shaped to ellipse-shaped, ¼″ to ⅜″ long, hairless capsule with many brown seeds. The capsule protrudes noticeably beyond the persistent sepals.

Northern bog violet (Viola nephrophylla) lower petal is bearded.

Taxonomy
Authorities do not agree on the classification of Viola sororia. Some authorities, including GRIN³⁸ and ITIS³⁷, list four varieties. In this classification, common blue violet is Viola sororia var. sororia and northern bog violet is Viola sororia var. affinis. Others, including PLANTS³, NCBI³⁴, Gleason & Cronquist⁴¹, and Voss⁴³, do not recognize any varieties. In this classification, common blue violet is Viola sororia and northern bog violet is Viola nephrophylla. The Minnesota DNR (MNTaxa²⁸) follows the latter classification.

Plant

Flower

Spur

Leaves

Location: Pennington County