Pycnanthemum tenuifolium has very fine, almost needle-like leaves on hairless, erect, branched stems that are 2’-3’ tall. Its tiny white flowers with two purple spots are produced in terminal clusters and open over an extended period, from middle summer into early fall. It has a very strong mint aroma when crushed. Like the other Mountain Mints, it spreads via rhizomes to form attractive colonies.
Pycnanthemum tenuifolium, also known as Narrowleaf (or Slender) Mountain Mint, has a wide natural range, found from Texas to Nebraska, northeastward into Canada and southeast to Florida. It is endemic to dry, open woods, dry prairies and fields as well as along roadsides, streams and in wet thickets.
Pycnanthemum tenuifolium prefers full sun to part shade and, unlike most Mountain Mint, dry to medium moist soils. It tolerates a wide range of soils and is happy in dry to damp situations. Great for naturalized areas and rain gardens. Definitely a pollinator favorite!