Lamium (dead-nettles) is a genus of about 30 species of flowering plants in the family Lamiaceae, of which it is the type genus. They are all herbaceous plants native to Eurasia and northern Africa, with several widely naturalised across much of the temperate world.
Description The genus includes both annual and perennial species; they spread by both seeds and stems rooting as they grow along the ground. They have square stemsParnell, J. and Curtis, T. 2012. Webb's An Irish Flora. p. 355. Cork University Press. and coarsely textured pairs of leaves, often with striking patterns or variegation. They produce double-lipped flowers in a wide range of colours.
Taxonomy In volume 2 of Species Plantarum published in 1753, the Swedish botanist Carl Linnaeus established genus Lamium by recognizing four species: Lamium album, Lamium purpureum, Lamium amplexicaule, and Lamium multifidum. The name Lamium is the primary generic name in use today.
, Plants of the World Online accepts the following species: Lamium album L. – (white dead-nettle) – widespread across Europe + northern Asia from Spain + Norway to Japan + Kamchatka; naturalised in New Zealand + North America Lamium amplexicaule L. – (henbit dead-nettle) – widespread across Europe and northern Asia from Spain + Norway to Japan + Kamchatka, as well as North Africa, Ethiopia, Azores, Madeira, Canary Islands; naturalised in New Zealand, Hawaii, South America + North America Lamium bakhtiaricum Jamzad – Iran Lamium bifidum Cirillo – Mediterranean from Portugal to Romania Lamium bilgilii Celep – Turkey Lamium cappadocicum Celep & Karaer – Turkey Lamium caucasicum Grossh. – Caucasus (southern European Russia, Armenia, Georgia, Azerbaijan) Lamium confertum Fr. – (northern dead-nettle) – northern Europe from Ireland to northern Russia; naturalised in Greenland + Iceland Lamium coutinhoi J.G.García – Portugal Lamium cyrneum Paradis – Corsica Lamium demirizii A.P.Khokhr. – Turkey Lamium eriocephalum Benth. – Turkey Lamium flexuosum Ten. – Spain, France, Italy, Algeria, Morocco, Tunisia Lamium galactophyllum Boiss. & Reut. – Turkey Lamium galeobdolon (L.) L. – (yellow archangel) – northern + central Europe and western Asia from Spain + Denmark east to Iran + Western Siberia; naturalised in North America, New Zealand, Madeira Lamium garganicum L. – Mediterranean + western Asia from Portugal to Kazakhstan + Saudi Arabia Lamium gevorense (Gómez Hern.) Gómez Hern. & A.Pujadas – Spain, Portugal, Corsica Lamium glaberrimum (K.Koch) Taliev – Crimea Lamium × holsaticum Prahl – central Europe (L. album × L. maculatum) Lamium hybridum Vill. – (cut-leaved dead-nettle) – Europe, Macaronesia, North Africa Lamium macrodon Boiss. & A.Huet – Turkey, Caucasus, Syria, Iran, Iraq Lamium maculatum L. – (spotted dead-nettle) – Europe + Middle East from Portugal to Turkey; also Gansu + Xinjiang Provinces of western China Lamium moschatum Mill. – eastern Mediterranean (Greece, Turkey, Syria, Palestine, Cyprus) Lamium multifidum L. – Turkey, Caucasus Lamium orientale (Fisch. & C.A.Mey.) E.H.L.Krause – Turkey, Syria, Palestine Lamium orvala L. – Austria, Italy, Hungary, Slovenia Lamium purpureum L. (red dead-nettle) – northern + central Europe and western Asia from Spain + Denmark east to Caucasus + Siberia; naturalised in Korea, Taiwan, North America, New Zealand, Argentina, Falkland Islands Lamium taiwanense S.S.Ying – Taiwan Lamium × schroeteri Gams – France, Switzerland, Hungary Lamium tomentosum Willd. – Turkey, Caucasus, Iran, Iraq Lamium tschorochense A.P.Khokhr. – Turkey Lamium vreemanii A.P.Khokhr. – Turkey
Several closely related genera were formerly included in Lamium by some botanists, including Galeopsis (hemp-nettles) and Leonurus (motherworts).
Etymology The generic name Lamium was used by Pliny the Elder in the first century AD. The name comes from the Greek laimos, which means "gullet", a reference to the gaping throat-like appearance of the corolla.
The common name "dead-nettle" has been derived from the German Taubnessel ("deaf nettle", or "nettle without a kernel"), and refers to the resemblance of Lamium album to the very distantly related stinging nettles, but unlike those, they do not have stinging hairs and so are harmless or apparently "dead".
Distribution and habitat The species are native to Europe, Asia. and northern Africa, but several have become very successful weeds of crop fields and are now widely naturalised across much of the temperate world.Altervista Flora Italiana, Genere Lamium includes photos and distribution maps for Europe and North AmericaFlora of China Vol. 17 Page 157 野芝麻属 ye zhi ma shu Lamium Linnaeus, Sp. Pl. 2: 579. 1753.
Ecology
Lamium species are used as food plants by the larvae of some Lepidoptera species including angle shades, setaceous Hebrew character and the Coleophora case-bearers C. ballotella, C. lineolea and C. ochripennella.
Cultivation Lamium species are widely cultivated as groundcover, and numerous cultivars have been selected for garden use. They are frost hardy and grow well in most soils. Flower colour determines planting season and light requirement: white- and purple-coloured flowered species are planted in spring and prefer full sun. The yellow-flowered ones are planted in fall (autumn) and prefer shade. They often have invasive habits and need plenty of room.
Cultural references Louise Glück, in her 1992 collection The Wild Iris has a poem entitled Lamium, which begins, "This is how you live when you have a cold heart./ As I do: in shadows, trailing over cool rock/ under the great maple trees."
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