Mentha longifolia, also known as horse mint, brookmint, fillymint or St. John's horsemint, is a species of plant in the family Lamiaceae. It is native to Europe excluding Britain and Ireland, western and central Asia (east to Nepal and far western China), and northern and southern (but not tropical) Africa.

Description

It is a very variable herbaceous perennial plant with a peppermint-scented aroma. Like many mints, it has a creeping rhizome, with erect to creeping stems 40–120 cm tall. The leaves are oblong-elliptical to lanceolate, 5–10 cm long and 1.5–3 cm broad, thinly to densely tomentose, green to greyish-green above and white below. The flowers are 3–5 mm long, lilac, purplish, or white, produced in dense clusters (verticillasters) on tall, branched, tapering spikes; flowering in mid to late summer. It spreads via rhizomes to form clonal colonies.

Taxonomy

Mentha longifolia has been widely confused with tomentose variant plants of the species Mentha spicata; it can be distinguished from these by the hairs being simple and unbranched, in contrast to the branched hairs of M. spicata.

  • Mentha longifolia var. amphilema <small>Briq. ex Rech.f.</small> - western Asia
  • Mentha longifolia var. asiatica <small>(Boriss.) Rech.f.</small> - western Asia to western China
  • Mentha longifolia var. austroafghanica <small>Rech.f.</small> - Afghanistan
  • Mentha longifolia subsp. capensis <small>(Thunb.) Briq.</small> - southern Africa
  • Mentha longifolia var. chlorodictya <small>Rech.f.</small> - Caucasus to western & central Asia
  • Mentha longifolia var. kermamensis <small>Rech.f.</small> - Iran
  • Mentha longifolia var. kotschyana <small>(Boiss.) Briq.</small> - eastern Turkey, Iran
  • Mentha longifolia subsp. longifolia <small>(L.) L.</small> - Europe, northwestern Africa
  • Mentha longifolia var. muqarrabica <small>Shinwari & Chaudhri</small> - Pakistan
  • Mentha longifolia subsp. noeana <small>(Briq.) Briq.</small> - Turkey east to Iran
  • Mentha longifolia var. petiolata <small>Boiss.</small> - northern Iraq to northern & western Iran
  • Mentha longifolia var. schimperi <small>(Briq.) Briq.</small> - Sinai to Arabian Peninsula
  • Mentha longifolia var. swatica <small>Shinwari & Chaudhri</small> - Pakistan
  • Mentha longifolia subsp. typhoides <small>(Briq.) Harley.</small> - northeastern Africa, southwestern Asia
  • Mentha longifolia subsp. wissii <small>(Launert) Codd.</small> - southwestern Africa

Hybrids

Mentha longifolia hybridizes with other Mentha species. Hybrids include:

  • Mentha × villosa-nervata <small>Opiz.</small> (hybrid with Mentha spicata) sharp toothed mint
  • Mentha × rotundifolia (L.) <small>Huds.</small>, 1782 (hybrid with Mentha suaveolens) false apple mint

Varieties and cultivars

Unlike other commonly cultivated species and hybrids of mint, there are few horticultural cultivars of M. longifolia. The only ones of note are:

  • M. longifolia Buddleia Mint Group (syn. M. longifolia 'Buddleia') - with silvered leaves. In addition, Mentha longifolia, like other Mentha species, is known to have important medicinal properties.

See also

  • Menthol
  • Pulegone

References