Mentha longifolia
species of plant
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 (16–47 in) tall. The leaves are oblong-elliptical to lanceolate, 5–10 cm (2.0–3.9 in) long and 1.5–3 cm (0.6–1.2 in) 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.
Infraspecies
The following subspecies and varieties are recognised:
Mentha longifolia var.
Begin with the source’s own compact description: “Mentha longifolia” is species of plant. The dossier treats that line as a proposition to test through Mentha, longifolia and species, not as a finished interpretation.
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Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Aug 26, 2026. The linked authority identifier is Q161924. None of the 0 selected statements returned an explicit reference.
Scientific names, classifications and consensus can change while older terminology persists in catalogues and historical literature. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Mentha longifolia” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.