Ricinus Species, Castor Bean, Caster Oil Plant

Ricinus communis

Family: Euphorbiaceae (yoo-for-bee-AY-see-ee) (Info)
Genus: Ricinus (RISS-i-nus) (Info)
Species: communis (KOM-yoo-nis) (Info)
View this plant in a garden



Tropicals and Tender Perennials

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Full Sun


Grown for foliage

Foliage Color:

Unknown - Tell us


4-6 ft. (1.2-1.8 m)


36-48 in. (90-120 cm)


USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Where to Grow:

Grow outdoors year-round in hardiness zone

Can be grown as an annual


All parts of plant are poisonous if ingested

Bloom Color:


Bloom Characteristics:

Unknown - Tell us

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Summer/Early Fall

Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:


Propagation Methods:

From seed; direct sow after last frost

Seed Collecting:

Collect seedhead/pod when flowers fade; allow to dry

Allow seedheads to dry on plants; remove and collect seeds

Wear gloves to protect hands when handling seeds

Seed does not store well; sow as soon as possible


This plant is said to grow outdoors in the following regions:

Decatur, Alabama

Dothan, Alabama

Tuscumbia, Alabama

Tuskegee, Alabama

Glendale, Arizona

Green Valley, Arizona

Mesa, Arizona

Phoenix, Arizona

Cabot, Arkansas

Mammoth Spring, Arkansas

Siloam Springs, Arkansas


Gardena, California

Oildale, California

Reseda, California

San Diego, California

Santa Barbara, California

Clifton, Colorado

Bartow, Florida

Boca Raton, Florida

Bradley, Florida

Casselberry, Florida

Defuniak Springs, Florida

Deltona, Florida

Fort Lauderdale, Florida

Hawthorne, Florida

Jacksonville, Florida(2 reports)

Miami, Florida

New Port Richey, Florida

Pensacola, Florida

Pompano Beach, Florida

Sarasota, Florida

Tampa, Florida

Conyers, Georgia

Villa Rica, Georgia

Honomu, Hawaii

Kapaa, Hawaii

Wailua Homesteads, Hawaii

Nampa, Idaho

Chicago, Illinois

Hinsdale, Illinois

Mount Prospect, Illinois

Murphysboro, Illinois

Washington, Illinois

Carmel, Indiana

Lexington, Indiana

Hutchinson, Kansas

Barbourville, Kentucky

Bowling Green, Kentucky(2 reports)

Ewing, Kentucky

Louisville, Kentucky

Coushatta, Louisiana

Centreville, Maryland

Bellaire, Michigan

Caledonia, Michigan

Lees Summit, Missouri

Saint Peters, Missouri

Billings, Montana

Dunellen, New Jersey

Roswell, New Mexico

Albany, New York

Brooklyn, New York

West Kill, New York

Yonkers, New York

Durham, North Carolina

Hamptonville, North Carolina

Raleigh, North Carolina

Dundee, Ohio

Newark, Ohio

Sandusky, Ohio

Toledo, Ohio

Hulbert, Oklahoma

Mccurtain, Oklahoma

Oklahoma City, Oklahoma

Sand Springs, Oklahoma

Freedom, Pennsylvania

Lansdowne, Pennsylvania

Mercer, Pennsylvania

Washington, Pennsylvania

Grenoble, Rhône-Alpes

Conway, South Carolina

Summerville, South Carolina

La Follette, Tennessee

Lafayette, Tennessee

Lawrenceburg, Tennessee

Lenoir City, Tennessee

Arlington, Texas

Austin, Texas

Houston, Texas

Kurten, Texas

La Vernia, Texas

Marquez, Texas

Mcallen, Texas

Nacogdoches, Texas

New Braunfels, Texas

Paris, Texas

Richmond, Texas

San Antonio, Texas(2 reports)

Spicewood, Texas

Trinity, Texas

Chesapeake, Virginia

Leesburg, Virginia

White Marsh, Virginia

Kalama, Washington

Seattle, Washington

Altoona, Wisconsin

Butte Des Morts, Wisconsin

Crivitz, Wisconsin

Racine, Wisconsin

show all

Gardeners' Notes:


On May 17, 2017, Rowan13 from catskills, NY (Zone 5a) wrote:

I received a plant already a foot high last year in zone 5 NY and it did very well. I saved the seeds over the Winter and would like to start them for this season, but I need to know if the outer coverings need to be removed before soaking them overnight?

Can you anyone provide any info?


On Mar 2, 2016, coriaceous from ROSLINDALE, MA wrote:

This species has naturalized in 34 states. As far north as Maine, it can overwinter as a self-sowing annual.

Where it is hardy, it's a suckering perennial shrub that can reach a height of 40'.

It's a heavy producer of light air-borne pollen which is highly allergenic. It's a common trigger for hayfever and asthma. In many people, it also causes a skin rash on contact. The seed pods are spiny.

In California, Florida, and Texas, it's on the official lists of species invasive of natural habitat.

Native to the eastern Mediterranean, east Africa, and India, it's now spread to most tropical areas around the world, where it's commonly considered invasive.


On Jul 26, 2013, longjonsilverz from Centreville, MD wrote:

I didn't expect this plant to return after winter here in Eastern Maryland, (zone 7) but it has been possibly both root hardy and/or reseeding every year now for at least 3 years. This is also after I removed the original plant. I now have multiple castor bean plants showing up around the area. Its not a big problem here, but I assume if you live in a slightly warmer area, this plant can be somewhat of a weed, not to mention the fact that it is poisonous too. However, if you're responsible and don't mind the extra maintenance, then this makes for a great fast growing tropical looking tree.


On Dec 19, 2008, Garden_Isle_Dave from Kapaa, HI wrote:

This stuff grows all over the place here in Hawaii, mostly the roadsides and other disturbed areas. I yank it whenever it sprouts in the yard, grows fast!

"Castor beans don't kill people....people kill people."


On Nov 23, 2008, Turtlegaby from Decatur, AL (Zone 8a) wrote:

I love Castor Beans, as they remind me to my childhood. My Mom grew them every year and gave me seeds shortly before she died. I planted them 10 years later and they still were all viable, germinated and grew to huge beautiful plants.


On Oct 9, 2007, thehandyman from Suches, GA wrote:

MOLE CHASER--Haven't used the plant to get rid of moles but purchased 75% castor oil solution from Home Depot. Works well for 6-8 weeks before need to reapply. It also seems to have run off the multitude of chipmunks that took up residence in my sloping yard.


On Sep 11, 2007, DanielVan from Nacogdoches, TX wrote:

I got seeds on ebay and planted them late june . Now they are 15 ft high and blossoming. I live in deep east texas . I got them to get rid of the moles but they don't seem to work i have moles everywhere.


On Jun 27, 2006, handbright from Coral Springs, FL (Zone 10b) wrote:

This plant was a volunteer in my garden this year, probably from bird droppings. It came up under an oak and in dappled light. As I write this, it is about 10 feet tall- all in about 8 weeks. For this zone and climate this is just a big "weed" but it was a welcomed addition to my garden this year.


On Feb 5, 2006, WUVIE from Hulbert, OK (Zone 7a) wrote:

Here in Northeastern Oklahoma we grow many castor bean plants each summer. The immense size of the plants, the hues of the foliage, I can't decide what I love best about them.

They are beautiful, tropical-looking and very tolerant of

Certainly I can appreciate the toxic warnings of the seeds, but let us remember we have toxic plants in our own homes, not to mention the numerous cans of chemicals and sprays right under our sinks. It is not a plant for the irresponsible or lazy person.

This plant can be enjoyed as well. If you do not wish for the hassle of the plant reseeding, cut the stalk off before it forms the seed pods. Very easy. When they pop up in the grass, mow those suckers down with the lawnmower.

This ... read more


On Jan 28, 2006, Gabrielle from (Zone 5a) wrote:

Castor bean is a fast growing annual in zone 5, but my information says it is hardy in zones 8-10. It adds a very tropical look to the garden, and some people use them as a quick "tree" for shade. Soaking aids germination of seeds.


On Oct 16, 2005, ineedacupoftea from Denver, CO wrote:

I would like to boast that this year, my Ricinus are 15 FEET TALL. -And I'm in Colorado! (My goal is 20' next year... ha ha) They will not be growing any taller, as the frost is fast approaching.

How To Grow: Set out as plantlets or seed en situ when nights are 50 F+ My experiments show best results with liberal peat and horse manure. Super rich soil means little to a plant in half-sun: Fullest sun is best. The plants grow fastest in heat if given enough water. (Even 100+ degrees) I have not fertilized.

Added Details: Wear gloves when handling; avoid contact with sap. This can leave a healthy person feeling rather ill... They have fairly shallow root systems and hollow stalks; characteristics which are less detrimental in high winds as might be exp... read more


On Aug 24, 2005, yvonneestelle from orillia, Ontario,
Canada wrote:

I have grown this plant in Toronto, Ontario. and Orillia, Ontario. it grows very good here , they grow to approx 6 feet tall.

I plant them with the little sponge end down. They grow, but it takes a couple of weeks for them to start to sprout.
thanks for sharing information regarding this plant


On Jul 23, 2005, hobocat from Moss Beach, CA, CA (Zone 9a) wrote:

In 1964 received a necklace strung with brightly speckled beans (that a friend had brought back from Jamacia as a gift, which, as a 12 year old, I absent-mindedly chewed on as I studied. I ate several of the chewey nutty-flavored beans and about 6 hours later got REALLY sick to my stomach. As the night went on, I emptied my stomach throwing everything up and still could not stop vomiting. At about 9 a.m. the next morning as the doctor was on the phone with my mother, and I was by then too weak to walk to the bathroom by myself, I leaned over the side of my bed to dry-heave into the wastebasket and saw the shells of the beans I had eaten the night before and had forgotten about.

I was driven to Grace New Haven Hospital from Southport, CT and by the time I arrived I was... read more


On Apr 2, 2005, vishva from Colombo,
Sri Lanka wrote:

This plant grows very fast. It conquers land that is not used in a small time. However having a caster tree in your garden can save other plants from termites etc;
It's seeds have a strong smell. That seed is used to extract oil. In sri lanka and India people use it's oil as a hair conditioner. It prevents loosing hair and stops itchiness. It also helps hair to grow fast and shine. It is also used as a herb in traditional medicine.


On Jan 15, 2005, gabagoo from Yonkers, NY (Zone 5b) wrote:

I have grown castors in containers & LOVED them. They don't get out of control that way - also not as HUGE as they get if planted in the ground.
I planted one in the ground in my mother's yard. It was HUGE!
LOL! She forbade me to ever do that again!


On Aug 22, 2004, aviator8188 from Murphysboro, IL (Zone 7a) wrote:

This attractive plant grows 16' tall in one summer here in southern Illinois! I just love the tropical look the Castor Bean adds to a garden next to my Needle Palms and Sabal minor!


On Aug 3, 2004, MotherNature4 from Bartow, FL (Zone 9a) wrote:

It was reported that planting castor beans in the vegetable garden during summer would rid the soil of nematodes. With caution, we planted seeds from wildlings and they grew huge. We carefully removed ALL flower heads as soon as they formed. When September rolled around, we pulled them up and planted our garden as usual. We had just as many nematodes as before. It didn't work for our garden in central Florida.


On Aug 2, 2004, NativePlantFan9 from Boca Raton, FL (Zone 10a) wrote:

Castor Bean is very invasive in my South Florida area. It is a very fast-growing weed that quickly colonizes undisturbed sites around farms such as sugarcane fields and canals. I see them growing in huge, weedy bunches around many of those places as well as others in my area. It is found throughout much of zones 8b, 9a, 9b, 10a, 10b, 11 and below through the Keys, mostly in the central and southern parts of the state, Florida. However, it may be a great houseplant indoors in a pot. However, it's bright-red seeds are extremely poisonous if ingested! If you have this plant, don't plant it outdoors, and keep away from young children!


On Jul 6, 2004, Commonsense from Rock Hill, SC (Zone 7b) wrote:

This is an incredible plant and I recommend it strongly to anyone who is willing to be careful in regard to its poisonous properties. I grew it in England, and now I'm growing it here in SC (Z7). At the present time (early July) my castor beans are well over six feet and still growing. The larger leaves are easily 3 feet across.

I will pinch off any flowers as soon as they form to prevent it setting seed.

These guys are a bit temperamental in regard to germination (start indoors 4-5 weeks before frost-free date), but once they get going they are true thugs, and they are marvelous.


On Jun 3, 2004, tigerlillydun from Sierra Vista, AZ (Zone 8b) wrote:

you can't kill this bugger,...it KEEPS coming back. Evryday Im out in the horse paddocks looking for sprouts of this nasty thing ! I would'nt want anything this toxic around animals or children.


On Jun 2, 2004, Karenn from Mount Prospect, IL (Zone 5a) wrote:

I had this plant last year as a focal point in front of my home (north side!). I saved a few of the seeds for my neighbor and myself to plant this year. Much to my surprise, I now have a half-dozen "babies" this year (without using the saved seeds!) where I had the plant last year. I live in zone 5a/4b; I cannot imagine how invasive this plant is in a more hospitable climate!


On Jun 1, 2004, TamiMcNally from Lake Placid, FL (Zone 9b) wrote:

Roots quickly and easily from stem cuttings.

It is great screening plant. I use mine as screens until my permanent plants grow tall enough.

Although it is listed as invasive in my area, I have not had any unwanted plants. However, I am growing mine in part shade and using no irrigation.


On Apr 15, 2004, foodiesleuth from Honomu, HI (Zone 11) wrote:

As in the area where Monocromatico lives, this plant tends to take over wildly in abandoned fields here...you see many of them growing in large clusters where sugar cane used to grow.
Ever since my son did a Science project in school many years ago, about poisonous plants I have had a healthy respect for this plant and will not plant it anywhere near my house as I'm worried about neighbor children and our pets.....also, another big reason, is I hated having to take spoonfuls of castor oil as a child!....ugh, can still taste it if I think about it.


On Apr 14, 2004, JaxFlaGardener from Jacksonville, FL (Zone 8b) wrote:

I've had these plants for the last 3 years, one on each side of the front entrance to my house. They make striking statements with their large leaves and perpendicular form. The winter of 2002, our temperatures in N. Florida went down to 14 F and the Castor plants froze to the ground and didn't return. This winter was much milder with temperatures barely reaching 32 F for a few hours. The Castor plants lost their leaves, but the stems stayed intact. The leaves have returned this spring from the nodule axis points on the stem and are more plentiful. My castor plants have never bloomed, probably because they are on the north side of my house and in fairly deep shade most of the time. They have grown this year to a height of about 12' and are still going. I will plant some new ones fr... read more


On Feb 3, 2004, junglejane wrote:

I live in Ocala Florida, I planted one caster bean seed beside my house, it grew straight up, with only one stock, the leaves stayed green with no purple tint in the veins, now (Feb 3rd 2004) it has a stalk of prickly seed pods. I enjoyed the nice pictures on your site. I must of planted it in the wrong spot.


On Apr 24, 2003, Monocromatico from Rio de Janeiro,
Brazil (Zone 11) wrote:

Riccinus comunis grows like a plague over here in any abandoned area, sometimes invading remainings of wild vegetation. One plant could be an interesting attraction in a garden, but people should be very careful to not lose control over it.


On Apr 9, 2003, ronb63 from Palmyra, NJ wrote:

I planted the seeds of this plant 3/31/03 ,they emerged 4/6/03.Prior to planting i soaked them in water 24 hrs.At the end of that period I could see grouth started already.It is now apr.10 and if it dont warm up around here I will have a huge display in my picture window.I live in NJ and right now it's 34 degrees.


On Apr 8, 2003, Luellen from Ellettsville, IN wrote:

I love the castor bean plant, its foliage is beautiful and it makes a wonderful backdrop in the large garden. I am growing seed now for planting next month (May). I live in zone 5 so this is an annual here. Last year I had two plants and they each grew to approximately 12 feet. I planted them to keep moles away but, that does not seem to work. Overall they are beautiful plants.


On Mar 22, 2003, babyduck wrote:

I've grown this plant as a hedge along my lawn and loved it. We have to grow it as an annuabecause I live in northern Ontario Canadaand the winters are very cold. 30 below sometimes.This year I've started the castor bean from the seeds I collected from the plant last fall. they are up about 1 inch now.They are a beautiful foliage plant.


On Mar 19, 2003, henkmaters wrote:

The Purple leaved variety (smaller) is known as R.Zanzibariensis. Its leaves are dark purple to almost black.


On Feb 28, 2003, albleroy from Wavre/ greenhous +/- 2500 species, IA wrote:

The castor oil plant is a species belonging to the family of the Euphorbiaceae, even if its appearance is completely different. This plant with herbaceous trunks can reach 12 meter height, but which generally does not grown over the 4 meters. Its palmate leaves can measure up to 60cm across: their colour (depending of the variety) can be deep green to purple. The flowers are grouped in glomerules at the end of the branches. The female flowers (green or carmine) on top (with red pistil depassing the flower) and the male (white) flowers under it. It is a wild plant in North-east Africa and in the Middle-East, but has spread all over the Med.basin, in Europe and the Canary Islands.
Ricinus communis is cultivated for the oil (Ricin oil in medicine) that can be extracted from the seed (... read more


On Jan 14, 2003, gynoben wrote:

I had recently acquired an oceanfront property in Central Florida. After wrestling dozens of these ugly monsterous "weeds" from the land I was trying to clear, I found I was dealing with the source of the notorious poison "ricin". I can see where in well defined landscape setttings the castor bean might be attractive but don't let them go to seed.


On Oct 14, 2002, Baa wrote:

A shrub from North Africa and Western Asia. Sometimes grown as an annual in more northerly climates or as a herbaceous perennial.

Has large, ovate, deeply lobed, mid green through to reddish, glossy leaves. Bears small, yellow flowers, the female flower has a prominent red stigma. Spiny seed capsules follow the flower.

Flowers mainly June-August

Loves fertile, well drained soil in full sun.

As others have said here, this plant is highly toxic.


On Sep 15, 2002, atelier wrote:

Impressive growth from late planting, Gorgeous coloured foliage, bloom and seed pods.


On Sep 1, 2002, muggie wrote:

I love my castor bean plant. It is large and a beautiful backdrop.


On Jul 8, 2002, oxmix wrote:

As a lover of Large ornamental annual plants, I have had alot of experience with this one, and believe me it can reach a height of 15 feet or more with leaves 3 feet across in its single season, given very rich soil and alot of water. As a architectural focal point in an annual garden, this giant(if you wish it to be) with interesting red flowers and spiked seed pods will amaze most anyone, when you tell them you planted a bean in the ground in May.

On the Negative side is its need to be securely staked if you are going for the big ones, In all instances where I did not Stake them with a rather sturdy 8 to ten foot pole
they fell over. Interestingly, if you have the strength to put them back up and restake them, they continue as if nothing has happened. 17 feet ... read more


On Jul 5, 2002, anabelle from Bakersfield, CA (Zone 9b) wrote:

The seeds to the Castor Bean Plant are very toxic. There is no other plant that in its natural state that is more POISONOUS. The plant produces burrs , and the burr pods burst open and contain usually 3 seeds. The seeds look alot like pinto beans and according to my hand book have a pleasent nutty like flavor. A whole bean swallowed, but not chewed, may not cause any harm. BUT 2 to 6 beans from this plant will KILL an adult person. Be very, very careful that, when putting beans down rodent holes, that you put them far enough down the holes so that , dogs, children, horses or any thing else can not get to them. My book does not list a antidote.


On Aug 11, 2001, Evert from Helsinki,
Finland (Zone 4b) wrote:

Castor Bean is perennial in warm places. Seeds are killing poisonous.


On Feb 9, 2001, dabble from Pisgah Forest, NC wrote:

Also called Mole Bean, this gorgeous plant will drive moles, voles and other pests from the area. The castor bean produces castor oil.


On Jan 4, 2001, lantana from (Zone 7a) wrote:

Grows in Heat Zones 12-1. Is considered an annual in all zones north of USDA zone 9, although some report it to be a perennial up to zone 7.


On Dec 2, 2000, gardener_mick from Wentworth, SD (Zone 4a) wrote:

Castor bean has extremely poisonous seeds! The plant grows to 8-10' tall and 3-4' wide. The flowers are red or red-green and the foliage is tinged red. It makes a great screen or backdrop, but should be used with caution. The flowers form small pompoms and are followed by prickly husks that have brown, speckled seeds. The plant is shrubby with leaves that are 1-3' and star-shaped. The leaves start out tinged red and turn glossy green as they grow.
Plants grow best in hot, humid climates and can become invasive in warm regions.

'Carmencita' - blooms early with bright red flowers and deep greenish brown flowers.