Stems freely branched, 1-4 dm, finely pubescent with minute, recurved hairs, often with spreading glandular hairs as well, but not hispid-setose; lvs 1.5-3 cm; verticils usually 2-4, few- fld; cal-lobes half as long as the canescent tube, only 3 mm even in fr; cor deep pink, 15-28 mm; 2n=16. Native of Eurasia, intr. in waste places or along the seashore, chiefly in the coastal states, but sometimes inland to Wis. June-Sept. Var. ladanum has lanceolate to ovate lvs to 15 mm wide and crenate-serrate with a few low teeth. (Var. latifolia) Var. angustifolia (Ehrh.) Wallr., much more common with us, has mostly linear and entire lvs rarely over 5 mm wide. (G. angustifolia)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.