Stems somewhat woody, trailing or scrambling, to 1 m, forming mats, the flowering branches ±erect; lvs glabrous, coriaceous, lance-elliptic, 3-5 cm, entire; cor-tube 8-
12 mm, the limb 2-3 cm wide; 2n=46. Native of s. Europe, often escaped from cult. into roadsides and open woods in our range. Apr., May.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.