Imperata cylindrica(L.) Raeusch.

cogongrass

WFO wfo-0000875631 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Imperata cylindrica, photographed by Greg Tasney
fig. a Greg Tasney, CC BY-SA 4.0 / 2022-06-13 / obs. 205980553

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 81 botanical countries

Regions where Imperata cylindrica is native: Algeria, Angola, Benin, Botswana, Burkina, Burundi, Cameroon, Canary Is., Cape Provinces, Cape Verde, Central African Republic, Chad, Comoros, Congo, DR Congo, Egypt, Equatorial Guinea, Eswatini, Ethiopia, Free State, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Gulf of Guinea Is., Ivory Coast, Kenya, KwaZulu-Natal, Lesotho, Liberia, Libya, Madagascar, Madeira, Malawi, Mali, Mauritius, Morocco, Mozambique, Namibia, Niger, Nigeria, Northern Provinces, Rwanda, Senegal, Sierra Leone, Socotra, Sudan-South Sudan, Tanzania, Togo, Tunisia, Uganda, Zambia, Zimbabwe, Afghanistan, Cyprus, East Aegean Is., Iran, Iraq, Kuwait, Lebanon-Syria, Oman, Palestine, Saudi Arabia, Sinai, Türkiye, Yemen, Albania, Baleares, Bulgaria, Corse, France, Greece, Italy, Kriti, NW. Balkan Pen., Portugal, Sardegna, Sicilia, Spain, Türkiye-in-Europe AlgeriaAngolaBeninBotswanaBurkinaBurundiCameroonCape ProvincesCentral African RepublicChadCongoDR CongoEgyptEquatorial GuineaEswatiniEthiopiaFree StateGabonGambiaGhanaGuineaGuinea-BissauGulf of Guinea Is.Ivory CoastKenyaKwaZulu-NatalLesothoLiberiaLibyaMadagascarMalawiMaliMoroccoMozambiqueNamibiaNigerNigeriaNorthern ProvincesRwandaSenegalSierra LeoneSudan-South SudanTanzaniaTogoTunisiaUgandaZambiaZimbabweAfghanistanCyprusEast Aegean Is.IranIraqKuwaitLebanon-SyriaOmanPalestineSaudi ArabiaSinaiTürkiyeYemenAlbaniaBulgariaCorseFranceGreeceItalyKritiNW. Balkan Pen.PortugalSiciliaSpainTürkiye-in-Europe Canary Is.Cape VerdeComorosMadeiraMauritiusBalearesSardegna
Native distribution of Imperata cylindrica, 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
Algeria ALG AFRICA
Angola ANG
Benin BEN
Botswana BOT
Burkina BKN
Burundi BUR
Cameroon CMN
Canary Is. CNY
Cape Provinces CPP
Cape Verde CVI
Central African Republic CAF
Chad CHA
Comoros COM
Congo CON
DR Congo ZAI
Egypt EGY
Equatorial Guinea EQG
Eswatini SWZ
Ethiopia ETH
Free State OFS
Gabon GAB
Gambia GAM
Ghana GHA
Guinea GUI
Guinea-Bissau GNB
Gulf of Guinea Is. GGI
Ivory Coast IVO
Kenya KEN
KwaZulu-Natal NAT
Lesotho LES
Liberia LBR
Libya LBY
Madagascar MDG
Madeira MDR
Malawi MLW
Mali MLI
Mauritius MAU
Morocco MOR
Mozambique MOZ
Namibia NAM
Niger NGR
Nigeria NGA
Northern Provinces TVL
Rwanda RWA
Senegal SEN
Sierra Leone SIE
Socotra SOC
Sudan-South Sudan SUD
Tanzania TAN
Togo TOG
Tunisia TUN
Uganda UGA
Zambia ZAM
Zimbabwe ZIM
Albania ALB EUROPE
Baleares BAL
Bulgaria BUL
Corse COR
France FRA
Greece GRC
Italy ITA
Kriti KRI
NW. Balkan Pen. YUG
Portugal POR
Sardegna SAR
Sicilia SIC
Spain SPA
Türkiye-in-Europe TUE
Afghanistan AFG ASIA-TEMPERATE
Cyprus CYP
East Aegean Is. EAI
Iran IRN
Iraq IRQ
Kuwait KUW
Lebanon-Syria LBS
Oman OMA
Palestine PAL
Saudi Arabia SAU
Sinai SIN
Türkiye TUR
Yemen YEM

Not drawn on the map: Socotra. 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 240 in flower of 573 examined

Proportion of examined Imperata cylindrica in flower, by month
Month In flower Examined Share 95% interval
Jan 13 30 43% 27% to 61%
Feb 10 29 34% 20% to 53%
Mar 25 52 48% 35% to 61%
Apr 80 154 52% 44% to 60%
May 28 96 29% 21% to 39%
Jun 15 43 35% 22% to 50%
Jul 8 26 31% 17% to 50%
Aug 12 26 46% 29% to 65%
Sep 8 27 30% 16% to 48%
Oct 18 33 55% 38% to 70%
Nov 12 27 44% 28% to 63%
Dec 11 30 37% 22% to 54%

Peak flowering in Oct. Each bar is the share of Imperata cylindrica 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. 240 of 573 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 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 1,996 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -0.7 °C 11.4 °C 17.7 °C
Warmest month, mean daily high 23.8 °C 29.7 °C 32.4 °C
Annual rainfall 659 mm 1,412 mm 3,215 mm
Rainfall in the driest quarter 22 mm 143 mm 515 mm

It is found where winters bring light 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 1,996 research-grade observations of Imperata cylindrica 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 52 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.

  • Arundo epigeios Forssk. ex Steud.
  • Calamagrostis lagurus Koeler
  • Imperata allang Jungh.
  • Imperata angolensis Fritsch
  • Imperata arundinacea Cirillo
  • Imperata arundinacea var. africana Andersson
  • Imperata arundinacea var. europaea Andersson
  • Imperata arundinacea var. glabrescens Buse
  • Imperata arundinacea var. indica Andersson
  • Imperata arundinacea var. koenigii (Retz.) Benth.
  • Imperata arundinacea var. latifolia Hook.f.
  • Imperata arundinacea var. pedicellata (Steud.) Debeaux
  • Imperata arundinacea var. thunbergii (Retz.) Stapf
  • Imperata cylindrica f. pallida Honda
  • Imperata cylindrica subsp. koenigii (Retz.) Tzvelev
  • Imperata cylindrica var. africana (Andersson) C.E.Hubb.
  • Imperata cylindrica var. cylindrica
  • Imperata cylindrica var. europaea (Andersson) Asch. & Graebn.
  • Imperata cylindrica var. koenigii (Retz.) Perkins
  • Imperata cylindrica var. latifolia (Hook.f.) C.E.Hubb.
  • Imperata cylindrica var. major (Nees) C.E.Hubb.
  • Imperata cylindrica var. parviflora Batt. & Trab.
  • Imperata cylindrica var. pedicellata (Steud.) Debeaux
  • Imperata cylindrica var. thunbergii (Retz.) T.Durand & Schinz

and 28 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.