Galeopsis tetrahitL.

Common hemp nettlebrittlestem hempnettlecommon hemp-nettle

WFO wfo-0000968061 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Galeopsis tetrahit, photographed by Alexis Tinker-Tsavalas
fig. a Alexis Tinker-Tsavalas, CC BY 4.0 / 2022-05-02 / obs. 195073508

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

The specimen a real sheet, in a real collection

Herbarium
The New York Botanical Garden
Accession
00198775
Filed as
Galeopsis tetrahit L.
Det. by
D. E. Atha 2010-01-01
Collected
D. E. Atha 2010-08-23
Origin
US
The sheet
View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 35 botanical countries

Regions where Galeopsis tetrahit is native: West Siberia, Albania, Austria, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Corse, Czechia-Slovakia, Denmark, East European Russia, Finland, France, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Krym, Netherlands, North European Russia, Northwest European Russia, Norway, NW. Balkan Pen., Poland, Portugal, Romania, Sardegna, South European Russia, Spain, Sweden, Switzerland, Ukraine West SiberiaAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCorseCzechia-SlovakiaDenmarkEast European RussiaFinlandFranceGermanyGreeceHungaryIrelandItalyKrymNetherlandsNorth European RussiaNorthwest European RussiaNorwayNW. Balkan Pen.PolandPortugalRomaniaSouth European RussiaSpainSwedenSwitzerlandUkraine Sardegna
Native distribution of Galeopsis tetrahit, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Albania ALB EUROPE
Austria AUT
Baltic States BLT
Belarus BLR
Belgium BGM
Bulgaria BUL
Central European Russia RUC
Corse COR
Czechia-Slovakia CZE
Denmark DEN
East European Russia RUE
Finland FIN
France FRA
Germany GER
Great Britain GRB
Greece GRC
Hungary HUN
Ireland IRE
Italy ITA
Krym KRY
Netherlands NET
North European Russia RUN
Northwest European Russia RUW
Norway NOR
NW. Balkan Pen. YUG
Poland POL
Portugal POR
Romania ROM
Sardegna SAR
South European Russia RUS
Spain SPA
Sweden SWE
Switzerland SWI
Ukraine UKR
West Siberia WSB ASIA-TEMPERATE

Not drawn on the map: Great Britain. We hold no public-domain boundary for this region, so it is listed rather than guessed at.

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 689 in flower of 712 examined

Proportion of examined Galeopsis tetrahit in flower, by month
Month In flower Examined Share 95% interval
Jan 0 0 too few examined
Feb 0 0 too few examined
Mar 0 0 too few examined
Apr 0 0 too few examined
May 0 3 too few examined
Jun 21 25 84% 65% to 94%
Jul 252 255 99% 97% to 100%
Aug 313 318 98% 96% to 99%
Sep 80 84 95% 88% to 98%
Oct 19 23 83% 63% to 93%
Nov 4 4 too few examined
Dec 0 0 too few examined

Peak flowering in Jul. Each bar is the share of Galeopsis tetrahit observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 689 of 712 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 7 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Where it actually grows measured, from 2,109 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -15.0 °C -5.4 °C 1.5 °C
Warmest month, mean daily high 17.8 °C 22.2 °C 25.4 °C
Annual rainfall 605 mm 896 mm 1,696 mm
Rainfall in the driest quarter 99 mm 173 mm 328 mm

It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 2,109 research-grade observations of Galeopsis tetrahit that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 54 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Galeopsis alpicola Nyman
  • Galeopsis beckii (K.Malý) Dalla Torre & Sarnth.
  • Galeopsis crenatifolia Sennen
  • Galeopsis gacognei Nyman
  • Galeopsis glaucocerata P.Fourn.
  • Galeopsis grandiflora Suter
  • Galeopsis ionantha Borbás
  • Galeopsis lactiflora Borbás
  • Galeopsis laramberguei Martrin-Donos
  • Galeopsis leucantha Jord.
  • Galeopsis michelianae Turra
  • Galeopsis neglecta Schult.
  • Galeopsis nodosa var. praecox (Jord.) St.-Lag.
  • Galeopsis nodosa var. regularis Gray
  • Galeopsis nodosum (Moench) Gray
  • Galeopsis persetosa Borbás
  • Galeopsis praecox Jord.
  • Galeopsis pseudotetrahit P.Fourn.
  • Galeopsis reichenbachii Reut.
  • Galeopsis silvestris Borbás
  • Galeopsis subtatrensis Borbás
  • Galeopsis tetrahit f. alba Farw.
  • Galeopsis tetrahit f. albiflora House
  • Galeopsis tetrahit subsp. glaucocerata P.Fourn.

and 30 more.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.