Mentha arvensis L., Corn Mint
Account Summary
Native, locally frequent. Circumpolar boreo-temperate, widely naturalised in both hemispheres.
1892; Praeger, R.Ll.; banks of Ballycassidy River.
July to October.
Growth form and preferred habitats
The mints are a rather difficult plant group to identify, due to their great variability, the ease with which they hybridise and the fact that numerous forms are grown in gardens and may escape or be discarded and then may cross with wild populations. The degree of hairiness, calyx shape, and stamen and petiole length are all significant distinguishing factors (Garrard & Streeter 1983).
M. arvensis is a very variable species and is usually considered a perennial, although it can behave as an annual in some situations. It is a rather slender, more or less hairy, sweetly or sickly scented mint (Clapham et al. 1987), depending on preferences and individual sense of smell! It produces simple or branched stems up 10-60 cm tall, and spreading branches issuing from a suckering, stoloniferous rootstock (Clapham et al. 1987). The creeping stolons grow very freely and take firm hold of ground it occupies, so the plant becomes very difficult to eradicate once it is well established (Grieve 1931).
When in flower, it is readily and easily distinguished from M. aquatica (Water Mint), since its flowers are all axillary, ie they are associated with leaves in the upper part of the plant. The erect stem is topped by a pair of opposite leaves, rather than by a terminal cluster of flowers as in Water Mint. Non-flowering plants are, however, a different matter, there being no reliable physical vegetative distinguishing characters to separate these two mint species, although in comparison, M. aquatica does have the more pungent odour of the two. Unfortunately, a good sense of smell and the ability to distinguish species by odour alone is not within everyone's capability.
The established strategy of M. arvensis is categorised as CR, ie it is a competitive ruderal that previously was widespread in B & I in arable fields of corn and other cultivated crops, especially on wetter ground (Grime et al. 1988, 2007). However, while it can be a vigorous coloniser, M. arvensis tends to be a rather poor competitor (Sinker et al. 1985).
In other parts of B & I, M. arvensis is a frequent plant of woodland rides, paths and clearings, marshy grassy waysides, disturbed waste places and margins of arable fields on damp to wet, intermittently flooded, acidic to neutral soils. It is essentially a lowland species, reaching an altitude of only around 370 m. M. arvensis frequently overlaps with M. aquatica and the two regularly hybridise. However, where water levels fluctuate markedly, or ground remains drier for relatively long periods, Corn Mint typically replaces Water Mint (K. Walker, in: Preston et al. 2002).
Fossil history
The hard nutlets of Mentha species make good macrofossils, being able to survive secondary deposition in glacial and periglacial deposits. As a result, they are almost exclusively used to record the members of the genus (Godwin 1975). Fossil records for M. aquatic, or for M. aquatica and M. arvensis together, are very similar and show these mints were present in every interglacial from the Pastonian onwards, proving the native status of both these species. However, fossils from the current Flandrian interglacial are sparse although they do increase later in time, and include finds from both Roman and Mediaeval sites (Godwin 1975).
Flowering reproduction
M. arvensis flowers from May to October, the small, 4 mm diameter flowers being borne in distant, compact, leafy whorls on the short, erect flowering branches. The bracts associated with the inflorescence are leaf-like, gradually decreasing in size upwards but always much longer than the flowers. Pedicels (flower stalks) are hairy, the calyx teeth, triangular, acute and much shorter than the bell-shaped, hairy calyx tube. The corolla is usually blue-lilac, but it can vary to pinkish or white (Clapham et al. 1987). The corolla is hairy inside and the four stamens are usually exerted from it. The flowers are pollinated by a variety of insect visitors (Garrard & Streeter 1983). The four fruit nutlets, 1.0 × 0.5 mm, are ellipsoid, slightly keeled, finely marked and pale yellow in colour (Butcher 1961).
Nutlets are shaken out of the calyx by wind or simply fall from the plant in autumn. If they drop into water, or are washed away in rainwater, they may float or drift away from the parent plant. The outer wall of the fruit nutlet of Mentha species contains a dry fleshy substance composed of air-cells with thin walls that allow the propagule to float. In the case of M. arvensis, floatation persists for only 36 hours or so (Praeger 1913, quoted in Ridley 1930, p. 222). Otherwise, the seed has no specialised dispersal mechanism, but they can survive burial and persist in the soil seed bank for five years or longer (Thompson et al. 1997).
Vegetative reproduction
The fact that, like other members of the Lamiaceae family, M. arvensis possesses a rhizome or rootstock that develops horizontally spreading, low-growing quadrangular stolons that can root at nodes along their length, confers additional reproductive potential to the species by means of this asexual growth process. Stoloniferous growth enables the plant to form clonal clumps or carpets, which enable the individual to compete more strongly than otherwise would be the case, allowing a greater level of persistence in the particular site occupied. The relative importance of seed production versus stolon growth to the colonising ability and stability of species populations remains unknown.
Fermanagh occurrence

M. arvensis is certainly the second most frequently recorded mint in the Fermanagh flora by a long margin. Apparently, this is an extremely common species in damp fields, lakeshores and roadsides around Upper Lough Erne. However, the superabundance of sites in this area is a reflection of the vast amount of data from unnecessarily detailed recording carried out in this particular region by the EHS Habitat Survey Team between 1986-7. Undoubtedly, this over sampling skews the distribution picture of many lakeshore species in Fermanagh and the current author (RSF) and RHN believe this is particularly so in this case. It appears rather doubtful that M. arvensis really is quite so frequent around Upper Lough Erne and so comparatively rare elsewhere. The tetrad map almost certainly reflects the extent of this unfortunate recorder bias, and as a result, is something of an artefact.
M. arvensis has been recorded in 73 Fermanagh tetrads, 13.8% of the total in the VC. There are no post-1975 records from five of the earlier tetrads recorded, losses very probably associated with the almost total move from arable to pasture agriculture in the survey area that has continued to the time of writing (2022).
As the common names applied to the plant 'Corn Mint' and 'Field Mint' indicate, to a large extent this is a species of tilled fields and damp, disturbed sandy ground. The modern scarcity of such habitats in Fermanagh suggests it would be more sparingly distributed than appears the case from the database records. On the other hand, M. arvensis certainly does occur on intermittently flooded lakeshores, especially in limestone districts, plus in open areas within woodland and on marshy ground along roadsides. Thus while some of its local habitats have been lost since the 1950s due to changes in agricultural practices, others suitable sites remain available.
British and Irish occurrence
Previously M. arvensis was very widespread throughout B & I as a cornfield weed, but has become increasingly scarce in N Scotland and entirely absent from Orkney and Shetland. The species has suffered a marked decline across B & I, especially from the English Midlands northwards since the 1950s. This appears to most probably reflect changes in agricultural practice, including drainage, cleaner crop seed, herbicides and a hugely significant shift from arable tillage towards pasture farming in the N & W (Braithwaite et al. 2006).
In Ireland, although it remains quite frequent, M. arvensis has become more scattered since the 1950s and has declined most in the centre of the island (Parnell & Curtis 2012).
European and world occurrence
M. arvensis is a polymorphic species containing several subspecies. It is widespread in most of Europe, N Asia and the Himalaya. A N Europe type is referred to as subsp. lapponica (Wahlenb.) Neum. The one area where the species is absent from is Iceland and Greenland (Hultén & Fries 1986 Map 1614). The form in E Asia is referred to as subsp. piperascens (Malinv.) Hara. Corn Mint is widely introduced as a weed elsewhere, including in N & C America, Java and New Zealand. M. arvensis s.l. belongs to the circumpolar boreo-temperate phytogeographic element (Hultén & Fries 1986, Map 1614).
Uses
Unlike Peppermint (M. × piperita) and Spear Mint (M. spicata), M. arvensis has not been used in herbal medicine, nor in the kitchen. Indeed, it can be a nuisance weed in Peppermint plantations where its strong odour would taint the valuable peppermint oil, spoiling its quality and value (Grieve 1931). The minty fragrance of Peppermint is replaced in M. arvensis by a smell described by Grigson (1955, 1987) as, "wet, mouldy gorgonzola". In 1798, William Sole published a survey of British mints in which he included 25 kinds. He made vivid attempts to pin down and describe their characteristic mint-like scents and he referred to Corn Mint having, "a strong fulsome mixed smell of mellow apples and gingerbread".
Names
The genus name 'Mentha' is the Latin name of a plant in Pliny after the Greek 'Minthe' and refers to a myth by Ovid about a nymph of that name. It is one of the oldest plant names still in use, going back perhaps 4,000 years (Gilbert-Carter 1964; Stearn 1992). The Latin specific epithet 'arvensis' means 'growing or pertaining to cultivated fields' (Stearn 1992).
Despite its strong, unpleasant smell, apart from 'Corn Mint', M. arvensis has been given several additional English common names, including 'Apple Mint' and 'Lamb's Tongue' (Grigson 1955, 1987). The English name 'Mint' is derived or evolved from the Old English 'minte', in its various forms a name common to the west Germanic languages and ultimately derived from the Latin 'menta', from the Greek 'minthe' (Grigson 1974).
The name 'Corn Mint' is widely known and used, the 'corn' element being a collective noun for all kinds, or fields, of cereal. The Old English 'corn' was already used to refer to the seed, not the standing crop. With the related Germanic words, 'corn' goes back to an Indo-european base meaning 'to wear down' or 'to wear away'. This implies that 'corn' was used in the same meaning as we now use the cognate word 'grain', eg 'a 'corn' of salt or of sand, equivalent to a 'grain' of salt or of sand. Cereals, peppers and other plants are said to produce corns or grains (Grigson 1974).
Threats
None.