Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Ricinus communis, Castorbean

Castorbean is a dramatic looking plant with large palmate green leaves with 5 or 7 to 12 or more lobes. The lobes are deeply serrated. Ricinus communisCastorbean flowers shown here are yellow (anthers) male flowers. Female flowers are red. Ricinus communisCastorbean may bloom year around or from June to November in cooler climates. Ricinus communisCastorbean fruits are spiny capsules which contain relatively large, highly poisonous seeds. Ricinus communisCastorbean is a perennial shrub or small tree. Plants may reach heights of 9 feet (3 m) or more. Plants are fast growing with sufficient water and high temperatures. Ricinus communisCastorbean fruits are spiny capsules which contain relatively large highly poisonous seeds. Ricinus communis
Castorbean naturally grows in disturbed areas, fields and roadsides. In central Arizona (Maricopa Co.) plants are often observed in the Salt River where permanent water occurs.  This species is native to southeastern Mediterranean Basin, Eastern Africa and India. It is now widespread through tropical regions. Ricinus communis

Scientific Name: Ricinus communis
Common Name: Castorbean

Also Called: Castor Bean, Castor-Bean, Agaliya, Lama Palagi, Maskerekur, Toto ni Vavalagi, Uluchula Skoki, (Spanish: Higuerilla, Higuera del Diablo, Ricino, Palma Christi)

Family: Euphorbiaceae, Spurge or Euphorbia Family

Synonyms: (Ricinus communis var. lividus, Ricinus communis var. megalospermus)

Status: Introduced

Duration: Perennial

Size: About 9 feet more or less, (3 m)

Growth Form: Shrub or Tree-like; plants ascending to erect; plants glabrous, fast growing with sufficient water and high temperatures, does not withstand cold temperatures; becomes suffrutescent with age, looks more herbaceous than tree-like.

Leaves: Green, sometimes with a reddish tinge, glossy, young leaves often dark reddish purple or bronze, long petiole, alternate, palmate with 5 to 7 or 12 lobes, lobes deeply serrate, glabrous.

Flower Color: Yellow (male) red (female)based on visible floral parts; inflorescence a terminal panicle; staminate without anthers, anthers yellow; pistillate flowers borne on tip of the inflorescent spike with 3 red styles; staminate flowers are proximal to the pistillate flowers; fruit spiny capsule, seeds (the caster bean) highly poisonous.

Flowering Season: June to November or year-round.

Elevation: Below 1,000 feet (300 m).

Habitat Preferences: Variable, personal observations suggest plants usually found near wet or damp disturbed areas, river bottoms; also found in disturbed areas, fields and roadsides.

Recorded Range: Native to southeastern Mediterranean Basin, Eastern Africa and India, now widespread through tropical regions. In Mexico it is recorded from Chiapas, Chihuahua, Coahuila, Colima, Federal District, Guanajuato, Guerrero, Jalisco, State of Mexico, Michoacán, Morelos, Nayarit, Oaxaca, Sinaloa, Sonora, Tabasco, Tamaulipas, Tlaxcala, Veracruz, Yucatan (Villaseñor and Espinosa, 1998). Widely grown as an ornamental.

North America & US County Distribution Map for Ricinus communis.

U.S. Weed Information: In North America Ricinus communis can be weedy or invasive according to the following authoritative sources: California Invasive Plant Council. 2006. California Invasive Plant Inventory. Cal-IPC Publication 2006-02 (1 February 2007). California Invasive Plant Council. Berkeley, California; Florida Exotic Pest Plant Council. 1999. Invasive plant list. Florida Exotic Pest Plant Council. Florida; Whitson, T.D. (ed.) et al.. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative Extension Services, University of Wyoming. Laramie, Wyoming. Plants included here may become weedy or invasive.

Invasive/Noxious Weed Information: No information available.

Wetland Indicator: No information available. In North America species has the following wetland designations: Arid West, FACU; Atlantic and Gulf Coastal Plain FACU; Eastern Mountains and Piedmont UPL; Great Plains FACU; Midwest FACU; Northcentral & Northeast FACU; Western Mountains, Valleys, and Coast FACU.
FACU = Facultative Upland, usually occur in non-wetlands, but may occur in wetlands.

Threatened/Endangered Information: No information available.

Genus Information: There is 1 species of Ricinus (monotypic).

Comments: In Arizona in the 1950's and 1960's this species was planted in gardens and yards to remove gophers. The belief was that the gophers would succumb after ingesting the toxic roots. There is no evidence to suggest this method was effective.
The seeds are the source of Castor oil.
This species contains the highly toxic ricin which is reportedly extremely allergenic. There are many "Cultivars" of Ricinus communis.
The plants are extremely dramatic in appearance and are used in parks and other public places.

Host Plant
Ricinus communis is the host plant of the Common Castor Butterfly, Ariadne merione, the Eri Silkmoth, Samia cynthia ricini and the Castor Semi-looper Moth, Achaea janata. It is also a food plant by the catterpillars of other butterfly species such as Hypercompe hambletoni and The Nutmeg (Moth) Anarta trifolii.

The genus Ricinus is a Latin word for tick which is a reference of the seed which has markings and a bump at the end that resemble certain ticks. The species epithet communis is from Old Latin meaning common, ordinary, commonplace or universal.

Castor oil has many uses in medicine and other applications.

Date Profile Completed: 07/14/2019
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search (accessed 07/14/2019)
The Plant List (2013). Version 1.1. Published on the Internet; (accessed 07/14/2019).
Mark H. Mayfield & Grady L. Webster 2012, Ricinus communis, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on July 14, 2019.
Wikipedia contributors, 'Ricinus', Wikipedia, The Free Encyclopedia, 24 March 2019, 02:12 UTC, [accessed 14 July 2019] - (accessed 10/06/2019)., Photographs and descriptions of the flowering and non-flowering plants of Missouri, USA
Villaseñor and Espinosa, 1998, Juana Mondragón Pichardo, Heike Vibrans (ed.), Conabio, Malezas de México, Euphorbiaceae; Ricinus communis; Higuerilla; (accessed 07/14/2019)
SEINet synonyms, scientific names, geographic locations, general information, (accessed 07/14/2019).