Coarse perennial herb, 50-150 cm. Stem stout, erect, sulcate, hoary-pubescent or scabrid. Leaves herbaceous, elliptic-ovate or oblanceolate, 25-30 by 8-15 cm, acute, base cuneate, entire; margin elsewhere entire or remotely serrate, pubescent above, softly pubescent or tomentose beneath; petiole 2-5 cm, scabrid. Flowers in lax or condensed, many-flowered axillary, often branched cymes. Bracts linear, lanceolate or ovate-lanceolate, 1-2 cm long. Calyx 1.5-2 cm long, hispid-tomentose; teeth linear subulate, 9-13 mm long. Corolla greenish white or yellow, 2.5-3.5 cm long, outside puberulent; throat narrow. Style and ovary glabrous. Nutlets smooth, glabrous, 6 by 3 mm.