Lemon-scented perennial, 4-8 dm; lvs long-petioled, ovate or deltoid-ovate, coarsely crenate, broadly obtuse to truncate at base, the main ones 4-7 cm, those of the branches much smaller and often cuneate at base; verticils few-fld, axillary to foliage lvs; pedicels 3-5 mm; cal 7-9 mm, the lips two-thirds as long as the tube; cor pale yellow, becoming white or pinkish, 8-15 mm, the lips 3 mm; 2n=32. Native of w. Asia, escaped from cult. and established in much of our range. June-Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.