Castor Plants – What’s in a Name?

Castor is used in many ways and not the least of which is as a pretty garden plant. But why is it called castor, and why is it called Ricinus?

Nomenclature Nerd Shares Science

Castor was first named Ricinus communis by the father of Botanical nomenclature, Carl Linnaeus. Take a look at the seeds. Carl sure did! The seed has markings and a bump at the end that resemble certain ticks, and the Latin word for tick is ricinus, so that is what he named the genus!



Meanwhile, over in zoology, there is also a genus Ricinus. There the name refers to an insect which is not a tick.  It is however a parasite found on birds. Two things named Ricinus?! Yes, this is possible because the names of animals and plants are governed by different nomenclature codes. Annoying, but possible.

Castor as a Common Name

The common name “castor oil” is said to come from people using the oil as a replacement for castoreum, a perfume base made from the dried perineal glands beavers. The Latin word for beaver is castor.


Other Castor Common Names

Another common name, palm of Christ, or Palma Christi, is from the “Doctrine of Signatures.” This is an old belief that every plant bears the “signature” of what it is to be used for.  Example, leaves that yield a milky sap must be good for helping lactation (milk production).


That large, hand-shaped leaf is supposed to signify that the hand of Christ is upon this plant and the oils in it. Castor oil is reputed ability to heal wounds and cure ailments. And the oil will cure you, if your ailment is constipation. If you decide to nibble on the plant itself, then you will get to meet your maker, so I guess that works too.

The houseplant known as “false castor plant” is Fatsia japonica. It’s not closely related at all, as a member of the Aralia Family. It’s not safe to eat either, but there’s a whole ‘nother post.

Using Castor

For more on how castor was and is used, visit the site Savor the Southwest. The Native Seri still use the plant today. There are also many other uses around the world, in industry, in medicine, and in the making of beauty products.  You can certainly use castor as a pretty garden plant – as I wrote about  – here.

The castor grown for oil production is not as showy as the garden varieties.

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Read more about castor in my book “Father Kino’s Herbs: Growing and Using Them Today” (Tierra del Sol Press). I hope you will consider purchasing a copy locally at Antigone Books, Magic Garden, Mostly Books, Rillito Nursery, Tohono Chul, and Tucson Botanical Gardens. Call first to make sure they have copies left.
You can also buy Father Kino’s Herbs on Amazon (link). If you buy the book there the Horticulture Therapy non-profit Tierra del Sol Institute will get a few pennies – at no extra cost to you.

© Article copyright Jacqueline A. Soule. All rights reserved. You must ask permission to republish an entire blog post or article. Okay to use a short excerpt but you must give proper credit. You must include a link to the original post on our site. No stealing photos.

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