Herbs, perennial. Roots: rhizomes present. Stems erect to ascending, to 1 m. Leaves spirally arranged; leaf sheaths with red hairs at summit; blade lanceolate-elliptic to lanceolate-oblong, 6--20 ´ 1--5 cm, apex acuminate. Inflorescences: distal cyme vestigial, included (very rarely 1-flowered and exserted); spathes clustered, subsessile, funnelform, 1.5--3.5 ´ 1.2--2 cm, margins connate basally, glabrous (rarely puberulent). Flowers bisexual (rarely staminate); petals all pale blue, proximal one smaller; staminodes 3; antherodes entirely yellow, cruciform. Capsules 3-locular, 2-valved, (5.5--)6--9 ´ 3--6 mm. Seeds 5, brown, (2.4--)3--5(--6) ´ 2.4--3.1 mm, smooth with a few, shallow, irregular depressions, farinose. n = 30. Flowering midsummer--fall. Wet places, especially swamps, river and stream banks, ditches, and bottomlands, shade or full sun; Ala., Ark., Del., D.C., Fla., Ga., Ill., Ind., Ky., La., Md., Miss., Mo., N.J., N.C., Okla., Pa., S.C., Tenn., Tex., Va.
From Flora of Indiana (1940) by Charles C. Deam
Found only in the southern part of the state in wet woods and sloughs and along streams. This is our largest species and usually forms colonies. No doubt all early reports of this species for the state should be referred to some other species. Commelina erecta of Gray, Man., ed. 5 is a synonym of this species and Coulter's and Young's reports for it from Jefferson County should be referred to Commelina virginica L.
Rhizomatous perennial; stem stout, erect or nearly so, to 12 dm, often widely branched; lf-blades lanceolate, long-acuminate, scabrous above, glabrous or finely hairy beneath, the main ones 10-20 נ2.5-5 cm; sheaths pilose-ciliate with red-brown hairs 2-5 mm, not prolonged into distinct auricles; spathes usually clustered toward the summit, sessile or short-peduncled, 2-3(-3.5) cm, nearly as wide when folded, the nerves connected by numerous cross-veins, the margins connate in the lower third; lower pet blue, scarcely reduced; fr 3-locular, the lower locules each 2-seeded, the upper one 1- seeded; 2n=60. Moist or wet woods; N.J. to Fla., w. to Ill., Kans., Okla., and Tex. (C. hirtella)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.