# Nerium

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Nerium
> Markdown URL: https://mediated.wiki/source/Nerium.md
> Source: https://en.wikipedia.org/wiki/Nerium
> Source revision: 1355814239
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{short description|Species of plant}}
{{Redirect|Arali|the underworld in Babylonian mythology|Irkalla}}
{{Redirect|Oleander}}
{{about|the species of plant|the multi-level marketing firm Nerium International|Neora LLC}}
{{Speciesbox
| name = Oleander
| image = Nerium oleander flowers leaves.jpg
| display_parents = 3
| genus = Nerium
| parent_authority = [L.](/source/Carl_Linnaeus)
| species = oleander
| authority = L.
| status = LC
| status_system = IUCN3.1
| status_ref = <ref>Lansdown, R.V. 2013. ''Nerium oleander''. The [IUCN Red List](/source/IUCN_Red_List) of Threatened Species 2013: e.T202961A13537523. https://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T202961A13537523.en. Accessed on 21 December 2022.</ref>
| synonyms = Numerous, see text
}}

'''''Nerium oleander''''' ({{IPAc-en|ˈ|n|ɪər|i|ə|m|...}} {{respell|NEER|ee|əm}}),<ref>{{cite book|author=Sunset Books|title=Sunset Western Garden Book|url=https://books.google.com/books?id=HpFZm3eHJucC|year=1995|publisher=Sunset Publishing Corporation|isbn=978-0-376-03850-0|pages=606–607}}</ref> commonly known as '''oleander, rose laurel''', '''be-still tree''' or '''rosebay''',<ref>{{Cite OED|rosebay|4058348783}}</ref> <ref name=":0">{{Cite book |last=Stewart |first=Amy |title=Wicked Plants: The Weed That Killed Lincoln's Mother and Other Botanical Atrocities |date=2009 |publisher=Algonquin Books |isbn=978-1565126831 |chapter=Oleander: Nerium Oleander}}</ref>is a shrub or small tree cultivated worldwide in temperate and subtropical areas as an ornamental and landscaping plant. It is the [only species](/source/Monotypic_taxon) currently classified in the genus '''''Nerium''''', belonging to subfamily [Apocynoideae](/source/Apocynoideae) of the [dogbane](/source/dogbane) family [Apocynaceae](/source/Apocynaceae). It is so widely cultivated that no precise region of origin has been identified, though it is usually associated with the [Mediterranean Basin](/source/Mediterranean_Basin).

Nerium grows to {{convert|2|-|6|m|ft|sigfig=1|abbr=off}} tall. It is most commonly grown in its natural shrub form, but can be trained into a small tree with a single trunk. It is tolerant to both drought and inundation, but not to prolonged frost. White, pink or red five-lobed flowers grow in clusters year-round, peaking during the summer. The fruit is a long narrow pair of follicles, which splits open at maturity to release numerous downy seeds.

Nerium is a [poisonous plant](/source/poisonous_plant) but its bitterness renders it unpalatable to humans and most animals, so poisoning cases are rare and the general risk for human mortality is low. Ingestion of larger amounts may cause nausea, vomiting, excess salivation, abdominal pain, bloody diarrhea and irregular heart rhythm. Prolonged contact with sap may cause skin irritation, eye inflammation and [dermatitis](/source/dermatitis).

==Description==
right|Detail of the candy-striped corona and feathery style of a single peach-colored flower|thumb

Oleander grows to {{convert|2|-|6|m|ft|sigfig=1|abbr=off}} tall, with erect stems that splay outward as they mature; first-year stems have a [glaucous](/source/glaucous) bloom, while mature stems have a grayish bark. The [leaves](/source/leaves) are in pairs or [whorls](/source/Whorl_(botany)) of three, thick and leathery, dark-green, narrow [lanceolate](/source/lanceolate), {{convert|5|-|21|cm|sigfig=1|in|abbr=off}} long and {{convert|1|-|3.5|cm|sigfig=2|frac=8|in|abbr=on}} broad, and with an entire [margin](/source/Leaf_margin) filled with minute reticulate venation web typical of [eudicots](/source/eudicots). The leaves are light green and very glossy when young, maturing to a dull dark green.

The flowers grow in clusters at the end of each branch; they are white, pink to red,<ref group=Note>The "Yellow Oleander" is ''[Cascabela thevetia](/source/Cascabela_thevetia)''</ref> {{convert|2.5|-|5|cm|in|sigfig=1|abbr=on}} diameter, with a deeply 5-lobed fringed [corolla](/source/Corolla_(botany)) round the central [corolla tube](/source/corolla_tube). They are often, but not always, sweet-scented.<ref group=Note>In the past, scented plants were sometimes treated as the distinct species ''N. odorum'', but the character is not constant and it is no longer regarded as a separate taxon.</ref> The fruit is a long narrow pair of [follicles](/source/follicle_(fruit)) {{convert|5|-|23|cm|in|sigfig=1|abbr=on}} long, which splits open at maturity to release numerous downy seeds.

== Taxonomy ==
''Nerium oleander'' is the only species currently classified in the genus '''''Nerium'''''. It belongs to (and gives its name to) the small tribe [Nerieae](/source/Nerieae) of subfamily [Apocynoideae](/source/Apocynoideae) of the dogbane family [Apocynaceae](/source/Apocynaceae). The genera most closely related thus include the equally ornamental (and equally toxic) ''[Adenium](/source/Adenium)'' <small>[G.Don](/source/G.Don)</small> and ''[Strophanthus](/source/Strophanthus)'' <small>[DC.](/source/DC.)</small> - both of which contain (like oleander) potent [cardiac glycosides](/source/cardiac_glycosides) that have led to their use as [arrow poisons](/source/arrow_poisons) in Africa.<ref name="Gurib-Fakim">{{cite book |last=Schmelzer |first=G.H. |url=https://books.google.com/books?id=7FJqgQ3_tnUC |title=Medicinal Plants |author2=A. Gurib-Fakim |publisher=Plant Resources of Tropical Africa |year=2008 |isbn=978-90-5782-204-9 |pages=43–49}}</ref> The three remaining genera ''[Alafia](/source/Alafia_(plant))'' <small>[Thouars](/source/Louis-Marie_Aubert_du_Petit-Thouars)</small>, ''[Farquharia](/source/Farquharia)'' <small>[Stapf](/source/Otto_Stapf_(botanist))</small> and ''[Isonema](/source/Isonema)'' <small>[R.Br.](/source/R.Br.)</small> are less well known in cultivation.

=== Synonymy ===
[[Image:Oleandro (ou espirradeira) com flores brancas 02.jpg|thumb|Tree in [Brazil](/source/Brazil), with white flowers only]]
The plant has been described under a wide variety of names that are today considered its synonyms:<ref>{{cite web |title=World Checklist of Selected Plant Families, entry for ''Nerium oleander'' |url=http://apps.kew.org/wcsp/synonomy.do?name_id=135196 |access-date=May 18, 2014}}</ref><ref>{{cite web |title=World Checklist of Selected Plant Families, entry for ''Nerium'' |url=http://apps.kew.org/wcsp/synonomy.do?name_id=135164 |access-date=May 18, 2014}}</ref>
{{div col|colwidth=20em}}
*''Oleander'' <small>Medik.</small>
*''Nerion'' <small>Tourn. ex St.-Lag.</small>
*''Nerion oleandrum'' <small>St.-Lag.</small>
*''Nerium carneum'' <small>Dum.Cours.</small>
*''Nerium flavescens'' <small>Spin</small>
*''Nerium floridum'' <small>Salisb.</small>
*''Nerium grandiflorum'' <small>Desf.</small>
*''Nerium indicum'' <small>Mill.</small>
*''Nerium japonicum'' <small>Gentil</small>
*''Nerium kotschyi'' <small>Boiss.</small>
*''Nerium latifolium'' <small>Mill.</small>
*''Nerium lauriforme'' <small>Lam.</small>
*''Nerium luteum'' <small>Nois. ex Steud.</small>
*''Nerium madonii'' <small>M.Vincent</small>
*''Nerium mascatense'' <small>A.DC.</small>
*''Nerium odoratissimum'' <small>Wender.</small>
*''Nerium odoratum'' <small>Lam.</small>
*''Nerium odorum'' <small>Aiton</small>
*''Nerium splendens'' <small>Paxton</small>
*''Nerium thyrsiflorum'' <small>Paxton</small>
*''Nerium verecundum'' <small>Salisb.</small>
*''Oleander indica'' <small>(Mill.) Medik.</small>
*''Oleander vulgaris'' <small>Medik.</small>
{{div col end}}

=== Etymology ===
The [taxonomic](/source/taxonomy_(biology)) name ''Nerium oleander'' was first assigned by [Linnaeus](/source/Carl_Linnaeus) in 1753.<ref>{{cite web| url=http://florida.plantatlas.usf.edu/Genus.aspx?id=832 | title=Nerium | publisher=Atlas of Florida Plants| access-date=2017-05-07}}</ref> The genus name ''Nerium'' is the [Latinized](/source/Latinisation_of_names) form of the [Ancient Greek](/source/Ancient_Greek) name for the plant ''nẽrion'' (νήριον), which is in turn derived from the Greek for water, ''nẽros'' (νηρός), because of the natural habitat of the oleander along rivers and streams.{{Citation needed|date=March 2025}}

The origins of the species name are disputed.  The word ''oleander'' appears as far back as the first century AD, when the Greek physician [Pedanius Dioscorides](/source/Pedanius_Dioscorides) cited it as one of the terms used by the Romans for the plant.<ref>{{cite book| title=De Materia Medica| author=Pedanius Dioscorides| page=V.42}}</ref> [Merriam-Webster](/source/Merriam-Webster) believes the word is a [Medieval Latin](/source/Medieval_Latin) corruption of [Late Latin](/source/Late_Latin) names for the plant: ''arodandrum'' or ''lorandrum'', or more plausibly ''rhododendron'' (another Ancient Greek name for the plant), with the addition of ''olea'' because of the superficial resemblance to the [olive](/source/Olea_europea) tree (''Olea europea'')<ref group=Note>Cf. [oleaster](/source/oleaster)</ref><ref>{{cite web| url=https://www.merriam-webster.com/dictionary/oleander | title=Oleander: Definition of Oleander | publisher=Merriam-Webster Dictionary| access-date=2017-06-25}}</ref><ref>{{cite web| url=http://www.etymonline.com/index.php?term=oleander | title=Oleander (n.) | publisher=Online Etymology Dictionary | access-date=2017-06-25}}</ref> Another theory posited is that ''oleander'' is the Latinized form of a Greek compound noun: ''οllyo'' (ὀλλύω) 'I kill', and the Greek noun for man, ''aner'', genitive ''andros'' (ἀνήρ, ἀνδρός).<ref name="Jashemski">{{cite book|author1=Wilhelmina Feemster Jashemski |author2=Frederick G. Meyer |title=The Natural History of Pompeii |url=https://books.google.com/books?id=3xfjyTqqR7IC&pg=PA133 |date=19 September 2002 |publisher=Cambridge University Press |isbn=978-0-521-80054-9|page=133}}</ref> ascribed to oleander's toxicity to humans.

The etymological association of ''oleander'' with the [bay laurel](/source/bay_laurel) has continued into the modern day: in France the plant is known as "laurier rose",<ref>{{cite web| url=https://www.collinsdictionary.com/dictionary/english-french/oleander| title=French translation of 'oleander'| publisher=Collinsdictionary.com| access-date=2017-12-29}}</ref> while the Spanish term, "Adelfa", is the descendant of the original Ancient Greek name for both the bay laurel and the oleander, ''daphne'', which subsequently passed into [Arabic](/source/Arabic) usage and thence to Spain.<ref>{{cite web| url=http://dle.rae.es/?id=0iV3sx7| title=adelfa| publisher=Diccionario de le lengua española| access-date=2017-12-29}}</ref>

The ancient city of [Volubilis](/source/Volubilis) in Morocco may have taken its name from the [Berber](/source/Berber_language) name ''alili'' or ''oualilt'' for the flower.<ref name="awhf">{{cite web|url=http://www.awhf.net/?p=573|title=Archaeological Site of Volubilis|publisher=African World Heritage Fund|access-date=2013-05-12|url-status=dead|archive-url=https://web.archive.org/web/20131020180151/http://www.awhf.net/?p=573|archive-date=2013-10-20}}</ref>

==Distribution and habitat==
[[File:A wadi west of Susa03.JPG|thumb|A [wadi](/source/wadi) in [Libya](/source/Libya)|alt=Oleander growing wild in a [wadi](/source/wadi), [Libya](/source/Libya)]]
''Nerium oleander'' is either native or naturalized to a broad area from northwest Africa through the [Mediterranean region](/source/Mediterranean_region) and warmer areas of the [Black Sea](/source/Black_Sea) region, Arabian Peninsula, southern Asia, and as far east as [Yunnan](/source/Yunnan) in southern parts of China.<ref name=Europa>[http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Nerium&SPECIES_XREF=oleander&TAXON_NAME_XREF=&RANK= Pankhurst, R. (editor). ''Nerium oleander'' L. ''Flora Europaea''.] [Royal Botanic Garden Edinburgh](/source/Royal_Botanic_Garden_Edinburgh). Retrieved on 2009-07-27.</ref><ref name=China>[http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200018424 Bingtao Li, Antony J. M. Leeuwenberg, and D. J. Middleton. "''Nerium oleander'' L.",  ''Flora of China''.] [Harvard University](/source/Harvard_University). Retrieved on 2009-07-27.</ref><ref name=Inchem>[http://www.inchem.org/documents/pims/plant/pim366.htm  INCHEM (2005). ''Nerium oleander'' L. (PIM 366). International Programme on Chemical Safety: INCHEM. Retrieved on 2009-07-27]</ref><ref name=Huxley>Huxley, A.; Griffiths, M.; Levy, M. (eds.) (1992). ''The New RHS Dictionary of Gardening''. [Macmillan](/source/Macmillan_Publishing). {{ISBN|0-333-47494-5}}.</ref> It can be found in tropical, subtropical, and temperate regions. The plant typically occurs in dry locations with a lot of sun near stream beds where it can alternatively tolerate long seasons of drought and inundation from winter rains.<ref name=":0" />

On the East Coast of the US, it grows as far north as [Virginia Beach](/source/Virginia_Beach%2C_Virginia), while in California and Texas miles of oleander shrubs are planted on [median strip](/source/median_strip)s.<ref>{{cite news | url=https://www.sacbee.com/news/local/transportation/back-seat-driver/article18001583.html | title=Will freeway oleander survive the drought? | author=Tony Bizjak | publisher=The Sacramento Bee | date=2015-04-09 | access-date=2017-05-14 }}</ref> There are estimated to be 25 million oleanders planted along highways and roadsides throughout the state of California.<ref name="sandiegoreader_2009-02-05"/> Because of its durability, oleander was planted prolifically on [Galveston Island](/source/Galveston_Island) in Texas after the disastrous [Hurricane of 1900](/source/1900_Galveston_Hurricane). They are so prolific that Galveston is known as the 'Oleander City'; an annual oleander festival is hosted every spring.<ref>{{cite web |url=http://oleander.org/oleander-history/|title=History - International Oleander Society |website=oleander.org |access-date=2016-04-10 |archive-url=https://web.archive.org/web/20170708072642/http://oleander.org/oleander-history/ |archive-date=2017-07-08 |url-status=dead}}</ref> [Moody Gardens](/source/Moody_Gardens) in Galveston hosts the propagation program for the International Oleander Society, which promotes the cultivation of oleanders. New varieties are hybridized and grown on the Moody Gardens grounds, encompassing every named variety.<ref name="moody">{{cite web| url=http://oleander.org/moody-gardens-the-ios/| title=Moody Gardens & the IOS| publisher=International Oleander Society| access-date=2019-04-15}}</ref>

Beyond the traditional Mediterranean and [subtropical](/source/subtropical_climate) range of oleander, the plant can also be cultivated in mild [oceanic climate](/source/oceanic_climate)s with the appropriate precautions. It is grown without protection in warmer areas in Switzerland, southern and western Germany and southern England and can reach great sizes in London and to a lesser extent in Paris<ref>{{cite web| url=http://www.pariscotejardin.fr/tag/laurier-rose/ | title=Paris côté jardin Archives de mots clés Laurier Rose | author=Alain Delavie | work=Paris côté jardin |date=2016-08-07 | access-date=2017-07-21}}</ref> due to the [urban heat island](/source/urban_heat_island) effect.<ref>{{cite web |url=https://www.rhs.org.uk/advice/profile?PID=810 |title=Oleander |website=[RHS Gardening](/source/Royal_Horticultural_Society) |access-date=2017-06-10 |archive-date=2021-11-05 |archive-url=https://web.archive.org/web/20211105052917/https://www.rhs.org.uk/advice/profile?pid=810 |url-status=dead }}</ref><ref>{{cite news| url=https://www.telegraph.co.uk/gardening/gardeningadvice/3350060/Gardening-advice-Thorny-problems.html |archive-url=https://ghostarchive.org/archive/20220112/https://www.telegraph.co.uk/gardening/gardeningadvice/3350060/Gardening-advice-Thorny-problems.html |archive-date=2022-01-12 |url-access=subscription |url-status=live | title=Gardening Advice: Thorny problems |author=Helen Yemm | publisher=The [Daily Telegraph](/source/Daily_Telegraph) | date=2008-09-19 | access-date=2017-06-10 }}{{cbignore}}</ref><ref>{{cite news| url=http://www.lefigaro.fr/jardin/2014/07/18/30008-20140718ARTFIG00057-au-jardin-ce-week-end-prolongez-vos-vacances-en-plantant-un-laurier-rose.php| title=Jardin: Prolongez vous vos vacances en plantant in laurier-rose| author=Marc Mennessier| publisher=[Le Figaro](/source/Le_Figaro)| date=2014-11-24| access-date=2018-02-25}}</ref> This is also the case with North American cities in the [Pacific Northwest](/source/Pacific_Northwest) like [Portland](/source/Portland%2C_Oregon),<ref>{{cite news| url=http://www.thedangergarden.com/2013/07/hey-check-out-that-parking-lot.html| title=Hey check out that parking lot!| author=Loree Bohl| publisher=Thedangergarden.com| date=2013-07-22| access-date=2018-02-24}}</ref> [Seattle](/source/Seattle), and [Vancouver](/source/Vancouver). Plants may suffer damage or die back in such marginal climates during severe winter cold but will rebound from the roots.{{Citation needed|date=March 2025}}

==Ecology==
Some invertebrates are known to be unaffected by oleander toxins, and feed on the plants. Caterpillars of the polka-dot wasp moth (''[Syntomeida epilais](/source/Syntomeida_epilais)'') feed specifically on oleanders and survive by eating only the pulp surrounding the leaf-veins, avoiding the fibers.  Larvae of the common crow butterfly (''[Euploea core](/source/Euploea_core)'') and oleander hawk-moth (''[Daphnis nerii](/source/Daphnis_nerii)'') also feed on oleanders, and they retain or modify toxins, making them unpalatable to potential predators such as birds, but not to other invertebrates such as spiders and wasps.<ref>{{cite web |title=Common Crow Butterfly |url=https://australian.museum/learn/animals/insects/common-crow-butterfly/ |publisher=The Australian Museum |access-date=23 October 2022}}</ref>

The flowers require insect visits to set seed, and seem to be [pollinated](/source/pollination) through a deception mechanism. The showy corolla acts as a potent advertisement to attract pollinators from a distance, but the flowers are nectarless and offer no reward to their visitors. They therefore receive very few visits, as typical of many rewardless flower species.<ref name=Herrera1991>{{cite journal |doi=10.1111/j.1095-8339.1991.tb02289.x |title=The reproductive biology of a riparian Mediterranean shrub, ''Nerium oleander'' L. (Apocynaceae) |journal=[Botanical Journal of the Linnean Society](/source/Botanical_Journal_of_the_Linnean_Society) |volume=106 |issue=2 |pages=147–72 |year=1991 |last1=Herrera |first1=Javier |bibcode=1991BJLS..106..147H }}</ref><ref>Shmida, A., Ivri, Y., and Cohen, D. The enigma of the oleander. Eretz VeTeva, January–February 1995 (in Hebrew).</ref> Fears of honey contamination with toxic oleander nectar are therefore unsubstantiated.{{Citation needed|date=March 2025}}

===Leaf scorch===
[[File:OleanderLeafScorch.jpg|thumb|Infected with ''[X. fastidiosa](/source/Xylella_fastidiosa)'' in [Phoenix](/source/Phoenix%2C_AZ)]]
A bacterial disease known as '''{{visible anchor|oleander leaf scorch}}''' ([''Xylella fastidiosa'' subspecies ''sandyi''](/source/Xylella_fastidiosa_subspecies_sandyi)<ref name="cabixf"/>) has become a serious threat to the shrub since it was first noticed in [Palm Springs](/source/Palm_Springs), California, in 1992.<ref name=scorch>{{cite web | url=http://ipm.ucanr.edu/PMG/PESTNOTES/pn7480.html | title=Oleander Leaf Scorch | publisher=University of California Agriculture & Natural Resources | date=April 2008 | access-date=2017-05-14}}</ref> The disease has since devastated hundreds of thousands of shrubs mainly in [Southern California](/source/Southern_California), but also on a smaller scale in [Arizona](/source/Arizona), [Nevada](/source/Nevada) and Texas.<ref>{{cite news | url=https://www.latimes.com/archives/la-xpm-1998-nov-21-hm-46038-story.html | title=How to Battle Oleander Leaf Scorch | author=U.C. Master Gardeners | work=[Los Angeles Times](/source/Los_Angeles_Times) | date=1998-11-21 | access-date=2017-05-14 }}</ref><ref name="Kathleen Norris Brenzel 2007">{{cite book |author=Kathleen Norris Brenzel |title=Sunset Western Garden Book |year=2007 |page=495}}</ref> The culprit is a bacterium which is [spread via insects](/source/insect_vector) (the [glassy-winged sharpshooter](/source/glassy-winged_sharpshooter) primarily) which feed on the tissue of oleanders and spread the bacteria. This inhibits the circulation of water in the tissue of the plant, causing individual branches to die until the entire plant is consumed.

Symptoms of leaf scorch infection may be slow to manifest themselves, but it becomes evident when parts of otherwise healthy oleanders begin to yellow and wither, as if scorched by heat or fire. Die-back may cease during winter dormancy, but the disease flares up in summer heat while the shrub is actively growing, which allows the bacteria to spread through the [xylem](/source/xylem) of the plant. As such it can be difficult to identify at first because gardeners may mistake the symptoms for those of [drought stress](/source/drought_stress) or nutrient deficiency.<ref>{{cite web | url=https://cals.arizona.edu/mohave/master_gardeners/lake_havasu/articles/oleander.pdf | title=Oleanders under attack | author=Laura Murphy | publisher=College of Agriculture and Life Sciences at the University of Arizona | date=2007-09-27 | access-date=2017-05-14 | archive-date=2021-12-05 | archive-url=https://web.archive.org/web/20211205210346/https://cals.arizona.edu/mohave/master_gardeners/lake_havasu/articles/oleander.pdf | url-status=dead }}</ref>

Pruning out affected parts can slow the progression of the disease but not eliminate it.<ref name=scorch/> This malaise can continue for several years until the plant completely dies—there is no known cure.<ref name="sandiegoreader_2009-02-05"/> The best method for preventing further spread of the disease is to prune infected oleanders to the ground immediately after the infection is noticed.

The responsible [pathogen](/source/pathogen) was identified as the [subspecies](/source/subspecies) ''sandyi'' by Purcell ''et al.'', 1999.<ref name="cabixf">{{cite journal|year=2022|volume=17|issue=21|last=Burbank|first=Lindsey|doi=10.1079/cabireviews202217021|id={{orcid|0000-0002-9614-1259}}|title=Threat of ''Xylella fastidiosa'' and options for mitigation in infected plants|s2cid=251514273|journal=[CABI Reviews](/source/CAB_International)|article-number=cabireviews202217021 |doi-access=free}}</ref>

== Cultivation ==
===History===
[[File:Lawrence Alma-Tadema An Oleander.jpg|thumb|right|''An Oleander'', an 1882 painting by [Lawrence Alma-Tadema](/source/Lawrence_Alma-Tadema). ]]
''Nerium oleander'' has a history of cultivation going back millennia, especially amongst the great ancient civilizations of the [Mediterranean Basin](/source/Mediterranean_Basin). Some scholars believe it to be the ''rhodon'' (rose), also called the 'Rose of Jericho', mentioned in apocryphal writings ([Sirach](/source/Book_of_Sirach) 24:14)<ref>{{cite book |title=Sirach 24:14}}</ref> dating back to between 450 and 180 BC.<ref name="Cyclopaedia">{{cite book |author=John McClintock |url=https://archive.org/details/cyclopaediaofbib04mccl |title=Cyclopaedia of Biblical, Theological, and Ecclesiastical Literature |year=1880 |page=[https://archive.org/details/cyclopaediaofbib04mccl/page/129 129]–130}}</ref><ref>{{cite news |author=Martha Modzelevich |title=Plants of the Bible: Oleander |publisher=flowersinisrael.com |url=http://www.flowersinisrael.com/Neriumoleander_page.htm |access-date=2018-06-12}}</ref>

The ancient Greeks had several names for the plant, including ''rhododaphne'', ''nerion'', ''rhododendron'' and ''rhodon''.<ref name="Cyclopaedia" /> Pliny confirmed that the Romans had no [Latin](/source/Latin) word for the plant, but used the Greek terms instead.<ref name="Pliny" /> [Pedanius Dioscorides](/source/Pedanius_Dioscorides) states in his 1st century AD pharmacopeia ''[De Materia Medica](/source/De_Materia_Medica)'' that the Romans used the Greek ''rhododendron'' but also the Latin ''Oleander'' and ''Laurorosa''. The Egyptians apparently called it ''scinphe'', the North Africans ''rhodedaphane'', and the [Lucanians](/source/Lucanians) (a southern Italic people) ''icmane''.<ref>{{cite book |author=Pedanius Dioscorides |url=https://www.scribd.com/document/57520993/The-Herbal-of-Dioscorides-the-Greek-Book-Four |title=De Materia Medica |page=V.42}}</ref>

Both Pliny and Dioscorides stated that oleander was an effective antidote to venomous snake bites if mixed with [rue](/source/Ruta_graveolens) and drunk. However, both rue and oleander are poisonous themselves, and consuming them after a venomous snake bite can accelerate the rate of mortality and increase fatalities.

A 2014 article in the medical journal ''[Perspectives in Biology and Medicine](/source/Perspectives_in_Biology_and_Medicine)'' posited that oleander was the substance used to induce hallucinations in the [Pythia](/source/Pythia), the female priestess of [Apollo](/source/Apollo), also known as the Oracle of [Delphi](/source/Delphi) in Ancient Greece.<ref>{{cite news |first=Haralampos|last=Harissis |title=A Bittersweet Story: The True Nature of the Laurel of the Oracle of Delphi |pages=351–60 |journal=[Perspectives in Biology and Medicine](/source/Perspectives_in_Biology_and_Medicine) |url=http://muse.jhu.edu/article/581067}}</ref> According to this theory, the symptoms of the Pythia's trances (''enthusiasmos'') correspond to either inhaling the smoke of or chewing small amounts of oleander leaves, often called by the generic term ''laurel'' in Ancient Greece, which led to confusion with the [bay laurel](/source/laurus_nobilis) that ancient authors cite.

In his book ''Enquiries into Plants'' of circa 300 BC, [Theophrastus](/source/Theophrastus) described (among plants that affect the mind) a shrub he called ''onotheras'', which modern editors render oleander: "the root of ''onotheras'' [oleander] administered in wine", he alleges, has a beneficial effect on mood:

<blockquote>The root of ''onotheras'' [oleander] administered in wine makes the temper gentler and more cheerful. The plant has a leaf like that of the [almond](/source/Almond_tree), but smaller, and the flower is red like a rose. The plant itself (which loves hilly country) forms a large bush; the root is red and large, and, if this is dried, it gives off a fragrance like wine.</blockquote>

In another mention, of "wild bay" (''Daphne agria''), Theophrastus appears to intend the same shrub.<ref>{{cite book |author=Theophrastus |title=Inquiry into Plants |publisher=[Loeb Classical Library](/source/Loeb_Classical_Library) |pages=I.9.3, IX.19.1 |translator=A. F. Hort}}</ref>

Oleander was a very popular ornamental shrub in Roman peristyle gardens; it is one of the flora most frequently depicted on murals in [Pompeii](/source/Pompeii) and elsewhere in Italy. These murals include the famous garden scene from the House of Livia at [Prima Porta](/source/Prima_Porta) outside Rome, and those from the House of the Wedding of Alexander and the Marine Venus in Pompeii.<ref>{{cite book |author=Farrar, Linda |title=Ancient Roman Gardens |publisher=Budding Books |year=2002 |isbn=978-1-84015-190-9 |pages=141–2,143–9}}</ref>

[Carbonized](/source/Carbonization) fragments of oleander wood have been identified at the [Villa Poppaea](/source/Villa_Poppaea) in [Oplontis](/source/Oplontis), likewise buried by the [eruption of Mount Vesuvius in 79 AD](/source/eruption_of_Mount_Vesuvius_in_79_AD).<ref name="Jashemski" /> They were found to have been planted in a decorative arrangement with [citron](/source/citron) trees (''Citrus medica'') alongside the villa's swimming pool.

[Herbaria](/source/herbarium) of oleander varieties are compiled and held at the [Smithsonian Institution](/source/Smithsonian_Institution) in Washington, D.C., and at [Moody Gardens](/source/Moody_Gardens) in Galveston, Texas.<ref name="moody" />

=== Ornamental gardening ===
[[File:Starr-090617-0851-Nerium oleander-flowers and variegated leaves-Ulumalu Haiku-Maui (24669336630).jpg|thumb|[Variegated](/source/Variegation) variety]]
[[File:White Oleander in Bloom.jpg|thumb|alt=[Joshua Tree](/source/Joshua_Tree%2C_California)|White variety in bloom]]

Oleander is a vigorous grower in warm subtropical regions, where it is extensively used as an [ornamental plant](/source/ornamental_plant) in parks, along roadsides and in private gardens. It is most commonly grown in its natural shrub form, but can be trained into a small tree with a single trunk.<ref name="culture">{{cite web |title=Oleander Culture |url=http://oleander.org/culture/ |access-date=2018-03-26 |publisher=International Oleander Society}}</ref> Hardy versions like white, red and pink oleander will tolerate occasional light frost down to {{convert|-10|C|F|abbr=on}},<ref name="Huxley" /> though the leaves may be damaged. The toxicity of oleander renders it deer-resistant and its large size makes for a good windbreak – as such it is frequently planted as a hedge along property lines and in agricultural settings.

The plant is tolerant of poor soils, intense heat, salt spray, and sustained drought – although it will flower and grow more vigorously with regular water. Although it does not require pruning to thrive and bloom, oleander can become unruly with age and older branches tend to become gangly, with new growth emerging from the base. For this reason gardeners are advised to prune mature shrubs in the autumn to shape and induce lush new growth and flowering for the following spring.<ref name="Kathleen Norris Brenzel 2007" /> Unless they wish to harvest the seeds, many gardeners choose to prune away the seedpods that form on spent flower clusters, which are a drain on energy.<ref name="Kathleen Norris Brenzel 2007" /> Propagation can be made from [cuttings](/source/cuttings_(plant)), where they can readily root after being placed in water or in rich organic potting material, like [compost](/source/compost).

In Mediterranean climates oleanders can be expected to bloom from April through October, with the heaviest bloom usually occurring between May and June. [Free-flowering](/source/Free-flowering) varieties like 'Petite Salmon' or 'Mont Blanc' require no period of rest and can flower continuously throughout the year if the weather remains warm.

In cold winter climates, oleander is a popular summer potted plant readily available at most nurseries. They require frequent heavy watering and fertilizing as compared to being planted in the ground, but oleander is nonetheless an ideal flowering shrub for patios and other spaces with hot sunshine. During the winter they should be moved indoors, ideally into an unheated greenhouse or basement where they can be allowed to go dormant.<ref name="culture" /> Once they are dormant they require little light and only occasional watering. Placing them in a space with [central heating](/source/central_heating) and poor air flow can make them susceptible to a variety of pests – [aphids](/source/aphids), [mealybugs](/source/mealybugs), [oleander scale](/source/oleander_scale), [whitefly](/source/whitefly) and [spider mites](/source/spider_mites).<ref>{{cite news |author=Elvin McDonald |date=1987-04-27 |title=Shedding Light on Growing Oleanders Indoors |publisher=Chicago Tribune |url=https://www.chicagotribune.com/1987/04/26/shedding-light-on-growing-oleander-indoors/ |access-date=2018-03-26}}</ref>

==== Colors and varieties ====
Oleander flowers are showy, profuse, and often fragrant, which makes them very attractive in many contexts. Over 400 cultivars have been named, with several additional flower colors not found in wild plants having been selected, including yellow, peach and [salmon](/source/Salmon_(color)). Many cultivars, like 'Hawaii' or 'Turner's Carnival', are multi-colored, with brilliant striped corollas.<ref>{{cite web |title=Blooming Oleanders of the American Collection |url=https://www.oleanderhaus.at/english/oleander-collections/blooming-oleanders-usa/ |publisher=Oleanderhaus.com}}</ref> The solid whites, reds and a variety of pinks are the most common. Double flowered cultivars like 'Mrs. Isadore Dyer' (deep pink), 'Mathilde Ferrier' (yellow) or 'Mont Blanc' (white) are enjoyed for their large, rose-like blooms and strong fragrance. There is also a [variegated](/source/variegation) form, 'Variegata', featuring leaves striped in yellow and white.<ref name="Kathleen Norris Brenzel 2007" /> Several dwarf cultivars have also been developed, offering a more compact form and size for small spaces. These include 'Little Red', 'Petite White', 'Petite Pink' and 'Petite Salmon', which grow to about {{convert|8|ft|m}} at maturity.<ref>{{cite news |author=Linda French |date=1989-07-01 |title=Gardening : ''Nerium oleander'' : Petite oleanders: Evergreen drought-tolerant dwarf shrubs with showy flowers |work=[Los Angeles Times](/source/Los_Angeles_Times) |url=https://www.latimes.com/archives/la-xpm-1989-07-01-vw-2382-story.html |access-date=2017-05-14}}</ref>

== Toxicity ==
[[File:Oleandrin-skeletal.svg|thumb|[Oleandrin](/source/Oleandrin), one of the toxins present in oleander]]

Oleander is a [poisonous plant](/source/poisonous_plant), containing the toxic steroidal aglycone cardenolide-type cardiac glycosides [odorosiside](/source/odorosiside), [adigoside](/source/adigoside), and [oleandrin](/source/oleandrin),<ref>Dey, Biplab & Alam, Faruk & Islam, Mohidul & Durgaprasad, Kemisetti & Yakin, Josef & Deka, Himangshu & Amin, Ruhul & Jyrwa, Rosamund & Judder, Moidul & kalita, Pallab. (2022). NERIUM OLEANDER: PHYTOCHEMISTRY, POISONING AND CASE STUDIES. 11. 3463-3476. 10.31032/IJBPAS/2022/11.7.6594.. </ref> especially when consumed in large amounts. These compounds  have a narrow [therapeutic index](/source/therapeutic_index) and are toxic when ingested. Adverse effects after ingestion include weakness, [diarrhoea](/source/diarrhoea), [nausea](/source/nausea), [vomiting](/source/vomiting), [headache](/source/headache), stomach pain, and death.<ref name="FH">{{Cite journal | last= Abid Aqsa, Mushtaq Ahmad, Muhammad Zafar, Sadia Zafar, Mohamed Fawzy Ramadan, Ashwaq T. Althobaiti, Shazia Sultana, Omer Kilic, Trobjon Makhkamov, Akramjon Yuldashev, Oybek Mamarakhimov, Khislat Khaydarov, Afat O. Mammadova, Komiljon Komilov |first= and Salman Majeed |date=December 2023|title= Foliar epidermal and trichome micromorphological diversity among poisonous plants and their taxonomic significance|journal=[Folia Horticulturae](/source/Folia_Horticulturae)|language=en|volume=35|issue=2|pages=243–274|doi= 10.2478/fhort-2023-0019 |issn=2083-5965|doi-access=free}}</ref>

Toxicity studies of animals concluded that birds and rodents were observed to be relatively insensitive to the administered oleander cardiac glycosides.<ref name="Szabuniewicz">{{cite journal |last1=Szabuniewicz |first1=Mirosław |authorlink1=Mirosław Szabuniewicz|last2=Schwartz |first2=WL |last3=McCrady |first3=JD |last4=Camp |first4=BJ |year=1972 |title=Experimental oleander poisoning and treatment |journal=[Southwestern Veterinarian](/source/Southwestern_Veterinarian) |volume=25 |issue=2 |pages=105–14}}</ref> Other mammals, however, such as dogs and humans, are relatively sensitive to the effects of cardiac glycosides and the clinical manifestations of "glycoside intoxication".<ref name="Szabuniewicz" /><ref>{{cite journal |last1=Szabuniewicz |first1=M |last2=McCrady |first2=J. D |last3=Camp |first3=B. J |year=1971 |title=Treatment of experimentally induced oleander poisoning |journal=[Archives internationales de Pharmacodynamie et de Thérapie](/source/%3Ade%3AArchives_internationales_de_Pharmacodynamie_et_de_Th%C3%A9rapie) |volume=189 |issue=1 |pages=12–21 |pmid=5167071}}</ref><ref>{{cite journal |last1=Hougen |first1=T. J |last2=Lloyd |first2=B. L |last3=Smith |first3=T. W |year=1979 |title=Effects of inotropic and arrhythmogenic digoxin doses and of digoxin-specific antibody on myocardial monovalent cation transport in the dog |journal=[Circulation Research](/source/Circulation_Research) |volume=44 |issue=1 |pages=23–31 |doi=10.1161/01.res.44.1.23 |pmid=758230 |doi-access=free}}</ref>
It is also hazardous to animals such as [sheep](/source/sheep), [horse](/source/horse)s, [cattle](/source/cattle), and other grazing animals,<ref>{{cite web |title=Oleander, rose laurel |url=https://poisonousplants.cvmbs.colostate.edu/plant/60 |website=Guide to Poisonous Plants |publisher=[Colorado State University](/source/Colorado_State_University) |access-date=9 September 2025}}</ref> with as little as 100 g being enough to kill an adult horse.<ref name="Knight">{{cite web |last=Knight |first=A. P. |year=1999 |title=Guide to Poisonous Plants: Oleander |url=http://www.vth.colostate.edu/poisonous_plants/report/report_detail_1.cfm?ID=334 |access-date=2009-07-27 |publisher=[Colorado State University](/source/Colorado_State_University) }}{{Dead link|date=August 2025 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Plant clippings are especially dangerous to horses, as they are sweet. In July 2009, several horses were poisoned in this manner from the leaves of the plant.<ref>{{cite web |last=Trevino |first=Monica |year=2009 |title=Dozens of horses poisoned at California farm |url=http://www.cnn.com/2009/CRIME/08/01/california.horses/index.html |access-date=2009-08-03 |publisher=CNN}}</ref>  Symptoms of a poisoned horse include severe diarrhea and abnormal heartbeat.<ref name=nmsu>{{cite web |title=Oleander Poisoning of Horses |last1=Turner |first1=Jason L. |last2=Torres |first2=Patrick |year=2023 |url=https://pubs.nmsu.edu/_b/B712/ |publisher=[New Mexico State University](/source/New_Mexico_State_University) |access-date=2026-04-30}}</ref> This is aptly reflected in the plant's [Sanskrit](/source/Sanskrit) name ''aśvamāra'' (अश्वमार), a compound of ''aśva'' "horse" and ''māra'' "killing".<ref>{{cite book |last=Bhattacharya |first=J. V. |title=A comprehensive Sanskrit-English lexicon: chiefly based on Professor Horace Hayman Wilson's Sanskrit-English Dictionary and compiled from various recent authorities for the use of schools and colleges. |year=1900 |page=74 |url=https://www.sanskrit-lexicon.uni-koeln.de/scans/csl-apidev/servepdf.php?dict=SHS&page=074-b |via=sanskrit-lexicon.uni-koeln.de}}</ref>

In reviewing oleander toxicity cases seen in-hospital, Lanford and Boor<ref name="Oleander toxicity">{{cite journal |last1=Langford |first1=Shannon D |last2=Boor |first2=Paul J |year=1996 |title=Oleander toxicity: An examination of human and animal toxic exposures |journal=[Toxicology](/source/Toxicology_(journal)) |volume=109 |issue=1 |pages=1–13 |doi=10.1016/0300-483X(95)03296-R |pmid=8619248|bibcode=1996Toxgy.109....1L }}</ref> concluded that, except for children who might be at greater risk, "the human mortality associated with oleander ingestion is generally very low, even in cases of moderate intentional consumption (suicide attempts)."<ref name="Oleander toxicity" /> In 2000, a rare instance of death from oleander poisoning occurred when two toddlers adopted from an orphanage ate the leaves from a neighbor's shrub in [El Segundo, California](/source/El_Segundo%2C_California).<ref>{{cite news |author=[Associated Press](/source/Associated_Press) |date=2000-07-25 |title=Oleander Poisoning Kills 2 Kids |publisher=apnews.com |url=https://www.apnews.com/8726086cea20740cc612907b1e48bda7 |access-date=2018-07-01}}</ref> Because oleander is extremely bitter, officials speculated that the toddlers had developed a condition caused by malnutrition, [pica](/source/Pica_(disorder)), which causes people to eat otherwise inedible material.<ref>{{cite news |author=Jessica Garrison |date=2000-07-26 |title=2 Toddlers Died from Oleander Poisoning, Coroner Says |work=[Los Angeles Times](/source/Los_Angeles_Times) |url=https://www.latimes.com/archives/la-xpm-2000-jul-26-me-59440-story.html |access-date=2018-06-28}}</ref>

=== Effects of poisoning ===
Ingestion of this plant can affect the gastrointestinal system, the heart, and the central nervous system. The main effect of cardiotoxic glycosides is positive [inotropy](/source/Inotrope). Glycosides bind to the sarcolemma transmembrane ATP<small>ase</small> of cardiac muscle cells and compete with K<sup>+</sup> ions, inactivating the enzyme. This results in an accumulation of Na<sup>+</sup> and Ca<sup>2+</sup> ions into the cardiac muscle cells, leading to stronger and faster heart contractions. Moreover, the increased amount of extracellular K<sup>+</sup> ions may lead to lethal hyperkalemia. Therefore, clinical features of oleander poisoning are similar to digoxin toxicity and include [nausea](/source/nausea), [diarrhea](/source/diarrhea), and vomiting due to stimulation of the area postrema of the medulla oblongata, neuropsychic disorders, and pathological motor manifestations.<ref name="Inchem" /> Cardiotoxic glycosides are also responsible for stimulating the vagus nerve (leading to sinus bradycardia) and the phrenic nerve (leading to hyperventilation), and lethal brady- and tachyarrhythmias, including asystole and ventricular fibrillation.<ref>{{Cite journal |last1=Bandara |first1=Veronika |last2=Weinstein |first2=Scott A. |last3=White |first3=Julian |last4=Eddleston |first4=Michael |date=2010-09-01 |title=A review of the natural history, toxinology, diagnosis and clinical management of Nerium oleander (common oleander) and Thevetia peruviana (yellow oleander) poisoning |url= |journal=Toxicon |volume=56 |issue=3 |pages=273–281 |doi=10.1016/j.toxicon.2010.03.026 |pmid=20438743 |bibcode=2010Txcn...56..273B |issn=0041-0101}}</ref> Oleander poisoning can also result in blurred vision, and vision disturbances, including halos appearing around objects.<ref name="sinai">{{Cite web |title=Oleander poisoning Information |url=https://www.mountsinai.org/health-library/poison/oleander-poisoning |access-date=2022-12-08 |website=[Mount Sinai Health System](/source/Mount_Sinai_Health_System) |language=en-US}}</ref> Oleander sap can cause skin irritations, severe eye inflammation and irritation, and allergic reactions characterized by dermatitis.<ref name="Goetz">{{cite web |last=Goetz |first=Rebecca. J. |year=1998 |title=Oleander |url=http://www.vet.purdue.edu/toxic/plant52.htm |url-status=dead |archive-url=https://web.archive.org/web/20100223014712/http://www.vet.purdue.edu/toxic/plant52.htm |archive-date=2010-02-23 |access-date=2009-07-27 |website=Indiana Plants Poisonous to Livestock and Pets |publisher=[Cooperative Extension Service, Purdue University](/source/Purdue_University)}}</ref>

The severity of the intoxication can vary based on the quantity ingested and an individual's physiological response, as well as the time of symptom onset after oleander ingestion: they can rapidly occur after drinking teas prepared with oleander leaves or roots or develop more slowly due to the ingestion of unprepared plant parts.<ref>{{Cite journal |last1=Mantelli |first1=Giovanni |last2=Carollo |first2=Massimo |last3=Losso |first3=Lorenzo |last4=Costantini |first4=Ilaria |last5=Morando |first5=Elia |last6=Bacchion |first6=Matilde |last7=Pizzuto |first7=Mauro |last8=Spagnuolo |first8=Letizia |last9=Ricci |first9=Giorgio |date=2023-12-01 |title=Laurel but Hardy: unintended poisoning, a case report of oleander misidentification as bay laurel |url= |journal=Toxicology Reports |volume=11 |pages=385–388 |doi=10.1016/j.toxrep.2023.10.010 |issn=2214-7500 |pmc=10598396 |pmid=37885923|bibcode=2023ToxR...11..385M }}</ref>

=== Treatment ===

Poisoning and reactions to oleander plants are evident quickly, requiring immediate medical care in suspected or known poisonings of both humans and animals.<ref name="Goetz" /> Induced vomiting and [gastric lavage](/source/gastric_lavage) are protective measures to reduce absorption of the toxic compounds. [Activated carbon](/source/Activated_carbon) may also be administered to help absorb any remaining toxins.<ref name="Inchem" /> Further medical attention may be required depending on the severity of the poisoning and symptoms. Temporary cardiac pacing will be required in many cases (usually for a few days) until the toxin is excreted.{{citation needed|date=November 2017}}

[Digoxin immune fab](/source/Digoxin_Immune_Fab) is the best way to cure an oleander poisoning if inducing vomiting has no or minimal success, although it is usually used only for life-threatening conditions due to side effects.<ref>{{cite journal |last1=Pao-Franco |first1=Amaris |last2=Hammond |first2=Tara N. |last3=Weatherton |first3=Linda K. |last4=DeClementi |first4=Camille |last5=Forney |first5=Scott D. |date=29 July 2017 |title=Successful use of digoxin-specific immune Fab in the treatment of severe ''Nerium oleander'' toxicosis in a dog |journal=[Journal of Veterinary Emergency and Critical Care](/source/Journal_of_Veterinary_Emergency_and_Critical_Care) |volume=27 |issue=5 |pages=596–604 |doi=10.1111/vec.12634 |pmid=28755414|s2cid=3798547 }}</ref>

Drying of plant materials does not eliminate the toxins. There is a wide range of toxins and secondary compounds within oleander, and care should be taken around this plant due to its toxic nature. Different names for oleander are used around the world in different locations, so, when encountering a plant with this appearance, regardless of the name used for it, one should exercise great care and caution to avoid ingestion of any part of the plant, including its sap and dried leaves or twigs. The dried or fresh branches should not be used for spearing food, for preparing a cooking fire, or as a food skewer. Many of the oleander relatives, such as the desert rose (''[Adenium obesum](/source/Adenium)'') found in East Africa, have similar leaves and flowers and are equally toxic.{{citation needed|date=November 2017}}

== Research ==
Drugs derived from ''N. oleander'' have been investigated as a treatment for cancer, but have failed to demonstrate clinical utility.<ref name=Henary>{{cite journal |doi=10.1200/jco.2011.29.15_suppl.3023 |title=Final results of a first-in-human phase I trial of PBI-05204, an inhibitor of AKT, FGF-2, NF-Kb, and p70S6K in advanced cancer patients |journal=Journal of Clinical Oncology |volume=29 |issue=15_suppl |pages=3023 |year=2011 |last1=Henary |first1=H. A |last2=Kurzrock |first2=R |last3=Falchook |first3=G. S |last4=Naing |first4=A |last5=Moulder |first5=S. L |last6=Wheler |first6=J. J |last7=Tsimberidou |first7=A. M |last8=Durand |first8=J |last9=Yang |first9=P |last10=Johansen |first10=M. J |last11=Newman |first11=R |last12=Khan |first12=R |last13=Patel |first13=U |last14=Hong |first14=D. S }}</ref><ref>{{cite journal |doi=10.1124/mi.8.1.8 |pmid=18332483 |title=Cardiac Glycosides as Novel Cancer Therapeutic Agents |journal=Molecular Interventions |volume=8 |issue=1 |pages=36–49 |year=2008 |last1=Newman |first1=R. A |last2=Yang |first2=P |last3=Pawlus |first3=A. D |last4=Block |first4=K. I }}</ref> According to the [American Cancer Society](/source/American_Cancer_Society), the trials conducted so far have produced no evidence of benefit, while they did cause adverse side effects.<ref name="Cancer">{{cite web |url=http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/herbsvitaminsandminerals/oleander-leaf |title=Oleander Leaf |publisher=[American Cancer Society](/source/American_Cancer_Society) |access-date=2018-03-26 |url-status=dead |archive-url=https://web.archive.org/web/20130315175936/http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/herbsvitaminsandminerals/oleander-leaf |archive-date=2013-03-15 }}</ref>

==Culture==

=== Oracle of Delphi ===
In a research study done by Haralampos V. Harissis, he claims that the laurel the [Pythia](/source/Pythia) is commonly depicted with is actually an oleander plant, and the poisonous plant and its subsequent hallucinations are the source of the oracle's mystical power and subsequent prophecies. Many of the symptoms that primary sources such as [Plutarch](/source/Plutarch) and [Democritus](/source/Democritus) report align with results of oleander poisoning. Harissis also provides evidence claiming that the word laurel may have been used to describe an oleander leaf.<ref>{{Cite journal |last=Harissis |first=Haralampos V. |date=2014 |title=A bittersweet story: the true nature of the laurel of the Oracle of Delphi |journal=Perspectives in Biology and Medicine |volume=57 |issue=3 |pages=351–360 |doi=10.1353/pbm.2014.0032 |issn=1529-8795 |pmid=25959349|s2cid=9297573 }}</ref>

=== Folklore ===
The toxicity of the plant makes it the center of an [urban legend](/source/urban_legend) documented on several continents and over more than a century. Often told as a true and local event, typically an entire family, or in other tellings a group of scouts, succumbs after consuming [hot dog](/source/hot_dog)s or other food roasted over a campfire using oleander sticks.<ref>{{cite web |url=http://www.snopes.com/horrors/poison/oleander.asp |title=Oleander Poisoning: snopes.com |last=Mikkelson |first=Barbara |publisher=[Snopes.com](/source/Snopes.com) |date=2011-07-31 |access-date=2015-11-29}}</ref> Some variants tell of this happening to [Napoleon](/source/Napoleon)'s or [Alexander the Great](/source/Alexander_the_Great)'s soldiers.<ref name="FullerMcClintock1986">{{cite book |author1=Thomas C. Fuller |author2=Elizabeth May McClintock |title=Poisonous Plants of California |url=https://archive.org/details/bub_gb_0-op0XwlDmQC |date=1 January 1986 |publisher=University of California Press |isbn=978-0-520-05569-8 |page=[https://archive.org/details/bub_gb_0-op0XwlDmQC/page/n84 78]}}</ref>

In Charleston, South Carolina, local folklore describes John and [Lavinia Fisher](/source/Lavinia_Fisher) as having poisoned the guests in their inn with oleander tea for the purpose of robbing them, though contemporaneous accounts do not corroborate the story.<ref>https://charlestoncitypaper.com/2010/12/21/bruce-orr-lets-john-and-lavinia-fishers-skeletons-out-of-the-closet/</ref>

There is an ancient account mentioned by [Pliny the Elder](/source/Pliny_the_Elder) in his ''[Natural History](/source/Natural_History_(Pliny))'',<ref name="Pliny">{{cite book |title=Natural History |author=Pliny |page=24.90}}</ref> who described a region in [Pontus](/source/Pontus_(region)) in Turkey where the honey was poisoned from bees having pollinated poisonous flowers, with the honey left as a poisonous trap for an invading army.<ref>{{cite book |title=Natural History |author=Pliny |page=21.77}}</ref><ref name="Hamilton1984">{{cite book |author=William John Hamilton |title=Researches in Asia Minor, Pontus and Armenia |url=https://books.google.com/books?id=FjHW2VXQVCwC&pg=PA160 |year=1984 |publisher=Georg Olms Verlag |isbn=978-3-487-41321-1|page=160}}</ref><ref>{{cite book |author=William John Hamilton |title=Researches in Asia Minor, Pontus, and Armenia: With Some Account of Their Antiquities and Geology &#91;in 1836&#93; |url=https://archive.org/details/bub_gb_hF0GAAAAQAAJ |year=1842 |publisher=John Murray |page=[https://archive.org/details/bub_gb_hF0GAAAAQAAJ/page/n406 384]}}</ref> The flowers have sometimes been mis-translated as oleander,<ref name="Jashemski"/> but oleander flowers are nectarless and therefore cannot transmit any toxins via nectar.<ref name=Herrera1991/>  The actual flower referenced by Pliny was either [Azalea](/source/Azalea) or ''[Rhododendron](/source/Rhododendron)'', which is still used in Turkey to produce a [hallucinogenic honey](/source/mad_honey).<ref name="Bryce 2014">{{cite web |last=Bryce |first=Emma |title=The Strange History of 'Mad Honey' |website=Modern Farmer |date=2014-09-04 |url=https://modernfarmer.com/2014/09/strange-history-hallucinogenic-mad-honey/ |access-date=2019-08-09}}</ref>

Oleander is the official flower of the city of [Hiroshima](/source/Hiroshima), having been the first to bloom following the atomic bombing of the city in 1945.<ref>{{Cite journal |last1=Tredici |first1=PD |last2=Tsuchida |first2=H |date=1993 |title=Hibaku trees of Hiroshima |url=http://arnoldia.arboretum.harvard.edu/pdf/articles/1993-53-3-hibaku-trees-of-hiroshima.pdf |journal=Arnoldia |pages=27 |archive-date=2014-05-21 |access-date=2019-08-09 |archive-url=https://web.archive.org/web/20140521032403/http://arnoldia.arboretum.harvard.edu/pdf/articles/1993-53-3-hibaku-trees-of-hiroshima.pdf |url-status=dead }}</ref>

=== In painting ===
[[File:WLA metmuseum Oleanders by Vincent van Gogh.jpg|thumb|''Oleanders'' by [Vincent van Gogh](/source/Vincent_van_Gogh)]]

Oleander was part of subject matter of paintings by famous artists including:
* [Gustav Klimt](/source/Gustav_Klimt), who painted ''Two Girls with an Oleander'' between 1890 and 1892.<ref>{{cite web| url=https://www.wadsworthshop.org/products/gustav-klimt-two-girls-with-oleander| title=Gustav Klimt, Two Girls with an Oleander| publisher=Wadsworth Atheneum Museum of Art}}</ref>
* [Vincent van Gogh](/source/Vincent_van_Gogh) painted his famous ''Oleanders'' in [Arles](/source/Arles) in 1888. Van Gogh found the flowers "joyous" and "life-affirming" because of their inexhaustible blooms and vigour.<ref>{{cite web| url=http://www.metmuseum.org/toah/works-of-art/62.24/| title=Oleanders| date=1888| publisher=The Metropolitan Museum of Art| access-date=2017-06-08}}</ref>
* Anglo-Dutch artist [Sir Lawrence Alma-Tadema](/source/Sir_Lawrence_Alma-Tadema) incorporated oleanders into his classically inspired paintings, including ''An Oleander'' (1882), ''Courtship'', ''Under the Roof of Blue Ionian Weather''<ref>{{cite book| title=Sir Lawrence Alma-Tadema | author=Russell Ash | publisher=Harry Abrams |
 year=1992}}</ref> and ''[A Roman Flower Market](/source/A_Roman_Flower_Market)'' (1868).
* ''The Terrace at Méric (Oleanders)'', an 1867 Impressionist painting by [Frédéric Bazille](/source/Fr%C3%A9d%C3%A9ric_Bazille).<ref>{{cite news| url=https://www.wikiart.org/en/frederic-bazille/the-terrace-at-m-ric-oleander| title=The Terrace at Méric (Oleanders)| publisher=wikiart.org| access-date=2018-06-08}}</ref>

=== In literature, film and music ===
* [Janet Fitch](/source/Janet_Fitch)'s 1999 novel ''[White Oleander](/source/White_Oleander)'' is centered around a young Southern California girl's experiences growing up in foster care after her mother is imprisoned for poisoning an ex-boyfriend with the plant.<ref>{{cite web| url=http://www.oprah.com/oprahsbookclub/White-Oleander-by-Janet-Fitch_1 | title= White Oleander | publisher=Oprah.com | date=1999-05-06 | access-date=2017-06-08}}</ref> The book was adapted into a 2002 [film of the same name](/source/White_Oleander_(film)) starring [Michelle Pfeiffer](/source/Michelle_Pfeiffer) and [Alison Lohman](/source/Alison_Lohman).
* In the 17th century AD [Farsi](/source/Farsi)-language book the ''[Jahangirnama](/source/Tuzk-e-Jahangiri)'', the Mughal emperor Jahangir passes a stream overgrowing with oleanders along its banks. He orders the nobles in his train to adorn their turbans with oleander blossoms, creating a "field of flowers" on their heads.<ref>{{cite news| url=https://www.thehindu.com/books/the-emperor-of-oleander-blossoms/article25451431.ece| title=The emperor of oleander blossoms| author=Parvati Sharma| work=The Hindu| date=2018-11-09| access-date=2019-04-23}}</ref>
* [Steely Dan](/source/Steely_Dan)'s 1973 song "[My Old School](/source/My_Old_School_(song))" contains the line "Oleanders growing outside her door, soon they're gonna be in bloom up in Annandale" in the second verse. It has been theorized that this reference is either a metaphor for a harmful relationship, or [marijuana](/source/Cannabis_(drug)), which is the subcontext of the song.<ref>{{cite magazine |title=The origins of Steely Dan |url=https://ew.com/article/2006/03/17/origins-steely-dan/ |magazine=Entertainment Weekly}}</ref>

==Gallery==
<gallery>
File:Nerium oleander peach.jpg|alt=Peach colored flowers
File:Nerium Oleander (yellow, unusual--may be Sue Hawley Oakes).jpg|alt=Unusual yellow-flowered variety. Cultivated, Galveston|Cultivated, [Galveston](/source/Galveston%2C_Texas)
File:Original Oleander Planting in Galveston.jpg|First oleander planted in [Galveston](/source/Galveston%2C_Texas) (1841)
File:Nerium Oleander(Red).jpg|alt=Red flower
File:Oleander Capsule Opens.jpg|[Follicle](/source/Follicle_(fruit)) spreading seeds
File:Nerium oleander pink.jpg|alt=Pink flowers and leaves
File:Nerium oleander Ouarzazate wild1.jpg|alt=Small bush
File:RoscheiderhofHerbst2018H3a.jpg|alt=Small tree
File:Flowers of Nerium oleander in West Bengal, India.jpg|alt=Flowers of N. oleander in West Bengal|''N. oleander'' in [West Bengal](/source/West_Bengal)
File:OleaUA2013.jpg| Closed buds of an oleander shrub near [Yalta](/source/Yalta), Ukraine
</gallery>

==See also==
* ''[Cascabela thevetia](/source/Cascabela_thevetia)'' (yellow oleander)
* [List of ineffective cancer treatments](/source/List_of_ineffective_cancer_treatments)
* [List of plants poisonous to equines](/source/List_of_plants_poisonous_to_equines)
* [List of poisonous plants](/source/List_of_poisonous_plants)
* [Tibesti-Jebel Uweinat montane xeric woodlands](/source/Tibesti-Jebel_Uweinat_montane_xeric_woodlands)

== Notes ==
{{Reflist|group=Note}}

== References ==
{{Reflist|refs=
<ref name="sandiegoreader_2009-02-05">
{{Cite news |last=Hamilton |first=Ron |date=5 February 2009 |title=Oleanders are Dying in San Diego |url=https://www.sandiegoreader.com/news/2009/feb/05/oleanders/ |work=[San Diego Reader](/source/San_Diego_Reader) |access-date=19 August 2017}}</ref>
}}

==External links==
* {{Wikispecies-inline}}
* {{Commons category-inline}}
* [https://www.clemson.edu/extension/hgic/plants/landscape/shrubs/hgic1079.html Oleander Facts].  [Clemson University](/source/Clemson_University). Retrieved on 2018-03-26.
* [https://web.archive.org/web/20050305061850/http://www.oleander.org/toxic.html Information on Oleander toxicity]. [International Oleander Society](/source/International_Oleander_Society). Retrieved on 2009-07-27.
* [https://web.archive.org/web/20060614180746/http://www.jardibotanic.bcn.es/22_6_eng.htm Plants of North Africa]. [Jardí Botànic de Barcelona](/source/Jard%C3%AD_Bot%C3%A0nic_de_Barcelona) Retrieved on 2009-07-27.
* [https://web.archive.org/web/20060614112441/http://www.itg.be/itg/DistanceLearning/LectureNotesVandenEndenE/index.htm Medical problems caused by plants: Plant Toxins, Cardiac Glycosides]. Erwin, Van den Enden. 2004. Illustrated Lecture Notes on Tropical Medicine. [Prince Leopold Institute of Tropical Medicine](/source/Prince_Leopold_Institute_of_Tropical_Medicine). Retrieved on 2009-07-27.
* [https://www.people.vcu.edu/~urdesai/car.htm#Cardiac%20Glycosides Cardiac glycosides]. Desai, Umesh R. [Virginia Commonwealth University](/source/Virginia_Commonwealth_University). School of Pharmacy. Retrieved on 2009-07-27.
* [https://www.snopes.com/horrors/poison/oleander.htm Legend of Oleander-poisoning at Campfire]. [Snopes](/source/Snopes). Retrieved on 2009-07-27.
* [https://web.archive.org/web/20110720190443/http://kielo.luomus.fi/laji/?t=Nerium+oleander&l=en Distribution over the world], ''N. oleander'', [University of Helsinki](/source/University_of_Helsinki)

{{Taxonbar|from1=Q3874774|from2=Q155833}}
{{Authority control}}

Category:Monotypic Apocynaceae genera
Category:Drought-tolerant trees
Category:Flora of North Africa
Category:Flora of Western Asia
Category:Garden plants of Africa
Category:Garden plants of Asia
Category:Medicinal plants
Category:Ornamental trees
Category:Shrubs
Category:Nerieae
Category:Flora of Lebanon
Category:Flora of the Mediterranean basin
Category:Constantly blooming plants
Category:Plants described in 1753
Category:Botanical taxa named by Carl Linnaeus

---
Adapted from the Wikipedia article [Nerium](https://en.wikipedia.org/wiki/Nerium) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Nerium?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.