Lepidium ruderaleL.

narrow-leaved pepperwortroadside pepperweed

WFO wfo-0000358755 Accepted WFO 2026-06 8 photographs CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Lepidium ruderale, photographed by Patrick Hacker
fig. a Patrick Hacker, CC BY 4.0 / 2022-06-13 / obs. 205804306
Lepidium ruderale, photographed by Denis Ibaev
fig. b Denis Ibaev, CC BY 4.0 / obs. 205102356
Lepidium ruderale, photographed by Екатерина Гущина
fig. c Екатерина Гущина, CC BY 4.0 / obs. 204688783
Lepidium ruderale, photographed by Pavel Kacl
fig. d Pavel Kacl, CC BY 4.0 / obs. 204131449
Lepidium ruderale, photographed by Alexis Tinker-Tsavalas
fig. e Alexis Tinker-Tsavalas, CC BY 4.0 / obs. 203424589
Lepidium ruderale, photographed by Alexis Tinker-Tsavalas
fig. f Alexis Tinker-Tsavalas, CC BY 4.0 / obs. 203419892
Lepidium ruderale, photographed by Grzegorz Grzejszczak
fig. g Grzegorz Grzejszczak, CC BY-SA 4.0 / obs. 203262102
Lepidium ruderale, photographed by Petr Harant
fig. h Petr Harant, CC BY 4.0 / obs. 202901917

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.

Native range 54 botanical countries

Regions where Lepidium ruderale is native: Altay, Buryatiya, Iran, Iraq, Irkutsk, Kazakhstan, Khabarovsk, Kirgizstan, Krasnoyarsk, Kuwait, Mongolia, North Caucasus, Primorye, Sakhalin, Tadzhikistan, Transcaucasus, Türkiye, Turkmenistan, Uzbekistan, West Siberia, Xinjiang, Yakutiya, West Himalaya, Albania, Austria, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Czechia-Slovakia, Denmark, East European Russia, Finland, France, Germany, Greece, Hungary, Italy, Krym, Netherlands, North European Russia, Northwest European Russia, Norway, NW. Balkan Pen., Poland, Portugal, Romania, South European Russia, Spain, Sweden, Switzerland, Türkiye-in-Europe, Ukraine AltayBuryatiyaIranIraqIrkutskKazakhstanKhabarovskKirgizstanKrasnoyarskKuwaitMongoliaNorth CaucasusPrimoryeSakhalinTadzhikistanTranscaucasusTürkiyeTurkmenistanUzbekistanWest SiberiaXinjiangYakutiyaWest HimalayaAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCzechia-SlovakiaDenmarkEast European RussiaFinlandFranceGermanyGreeceHungaryItalyKrymNetherlandsNorth European RussiaNorthwest European RussiaNorwayNW. Balkan Pen.PolandPortugalRomaniaSouth European RussiaSpainSwedenSwitzerlandTürkiye-in-EuropeUkraine
Native distribution of Lepidium ruderale, 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.
RegionTDWG codeContinent
Albania ALB EUROPE
Austria AUT
Baltic States BLT
Belarus BLR
Belgium BGM
Bulgaria BUL
Central European Russia RUC
Czechia-Slovakia CZE
Denmark DEN
East European Russia RUE
Finland FIN
France FRA
Germany GER
Greece GRC
Hungary HUN
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
South European Russia RUS
Spain SPA
Sweden SWE
Switzerland SWI
Türkiye-in-Europe TUE
Ukraine UKR
Altay ALT ASIA-TEMPERATE
Buryatiya BRY
Iran IRN
Iraq IRQ
Irkutsk IRK
Kazakhstan KAZ
Khabarovsk KHA
Kirgizstan KGZ
Krasnoyarsk KRA
Kuwait KUW
Mongolia MON
North Caucasus NCS
Primorye PRM
Sakhalin SAK
Tadzhikistan TZK
Transcaucasus TCS
Türkiye TUR
Turkmenistan TKM
Uzbekistan UZB
West Siberia WSB
Xinjiang CHX
Yakutiya YAK
West Himalaya WHM ASIA-TROPICAL

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 30 in flower of 178 examined

Peak flowering in May. Each bar is the share of Lepidium ruderale 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. 30 of 178 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 5 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.

Also published as 12 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.

  • Crucifera ruderalis E.H.L.Krause
  • Iberis ruderalis Crantz
  • Lepidium ambiguum Lange
  • Lepidium glaucescens Dumort.
  • Lepidium ruderale f. incanum Grütter
  • Lepidium texanum Buckley
  • Nasturtiastrum ruderale (L.) Gillet & Magne
  • Nasturtioides inconspicua Medik.
  • Nasturtium ruderale Scop.
  • Senckenbergia ruderalis G.Gaertn., B.Mey. & Scherb.
  • Thlaspi ruderale All.
  • Thlaspi tenuifolium Lam.

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.