- To 1.5m tall, dichotomously branching above, from fibrous roots or slender rhizomes, stout, erect, 4-angled, green to purple (in strong sun), hollow, often glaucous, glabrous or sparse pubescent (especially at the nodes), fragrant.
- Opposite, decussate, petiolate. Petiole to +/-4cm long, puberulent, with adaxial groove (pubescent in groove), purple. Blade to +10cm long, 6cm broad, scabrous above, punctate, tomentoulose on veins and midrib below, truncate to subcordate at base, serrate, acuminate, fragrant.
- Single terminal capitate cluster of +/-75 flowers. Flowers on pedicels to 1mm long. Pedicels tomentoulose. Clusters subtended by involucre of whorled foliaceous bracts.
Bracts subtending the inflorescence.
- Corolla bilabiate, pink. Corolla tube to -2cm long, contracted and white at base in calyx tube, pink above and tomentoulose. Upper lip to 1.5cm long, folding around stamens and style, reflexed with age, pubescent externally with long cilia at apex, glabrous internally. Lower lip to 1.7cm long, with central linear lobe (notched at apex), glabrous internally, pubescent externally. Stamens 2, adnate at apex of corolla tube, exserted from upper lip of corolla. Filaments to 1.4cm long, white, glabrous. Anthers 2mm broad, with brown-purple margin. Style to +3cm long, white below, pinkish-purple at apex, pubescent. Stigma unequally two lobed. Ovary of 4 nutlets. Nutlets to 2mm long in fruit, blackish. Calyx tube to 1cm long, -2mm in diameter, 5-lobed, puberulent, 13-ribbed (nerved). Lobes linear-attenuate, 1.1mm long, dark purple, with spreading cilia on outer margin between lobes and dense erect cilia on margin internally.
- May - August.
- Prairies, fields, open rocky woods, glade margins, thickets, roadsides, railroads.
- Native to U.S.
- This striking species can be found throughout Missouri but is apparently absent in the extreme southeastern section of the state. It is an easy species to ID in the field. The brilliant, dense flower heads and pleasant fragrance make the plant a perennial favorite, literally. The plant is a big favorite among butterfly gardeners and is widely cultivated. It grows easily from seed.
The leaves have been used traditionally as medicine but today are used to flavor teas. The flowers can be used to dress up a salad or garnish a meal.
The species is sometimes broken up into different varieties but these integrate so I won't mention them.
Photographs taken at Logan Creek, Reynolds County, MO., 7-17-03.