Ricinus communis

Ricinus communis (Castor bean)

A friend once asked me why I bothered growing castor beans. Well if not for the foliage, the architectural form, or those cute fuzzy seed pods, maybe it was just to make sure I got on a terrorist watchlist somewhere for being a regular purchaser of seed.

The plant is highly poisonous (hence deer-resistant) and the beans can be processed to make a very potent poison. (A local seed company reported a big sale of seed to some guy who turned out just to be disturbed, not dangerous.) From the Cornell poisonous plants website:

In 1978, ricin was used to assassinate Georgi Markov in 1978, a Bulgarian journalist who spoke out against the Bulgarian government. He was stabbed with the point of an umbrella while waiting at a bus stop near Waterloo Station in London. They found a perforated metallic pellet embedded in his leg that had presumably contained the ricin toxin.

Castor bean

Castor bean

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3 thoughts on “Ricinus communis”

  1. I live in Minnesota and a friend gave me some seeds to plant. Do I start them in the house before spring? They are not out of the fuzzy pod, how do I break that open, and then what do I do with them? Do they need to be in full sunlight?

  2. Mary:

    As far as timing goes, I treat them a lot like tomatoes: Start them inside 6 to 8 weeks before average last frost date. (I know some folks who start them even earlier than that so they can transplant out 3- to 4-foot plants. Move them outside gradually to harden them off. Transplant them after the soil has warmed up and danger of frost has passed.

    They are tropical plants that need rich soil, full sun, lots of water and warm temps to reach their full potential. In a good year, I’ve had them pushing 8 feet or so. But they’ll go taller. I suppose you could grow them in part shade. They’d still make attractive plants, only probably a lot smaller and maybe a little leggy.

    The plant in the top picture leaned over early in the season and became a nice bushy, multi-stemmed plant. It was so attractive that way, I’m thinking about pinching off the leader on some this year where I need to fill space horizontally, rather than vertically.

    The seeds are poisonous, so handle them with care. (They’re a source of the poison ricin, I’m guess from the genus name, Ricinus.) I coax them out of the fuzzy seed pods with a pocket knife. I also soak them overnight in warm water and/or nick the hard seed coat with a knife to speed germination. Even then, germination can be erratic, with some jumping right out of the pots and others waiting for weeks before making an appearance.

    Hope this is helpful.

  3. GREAT SITE! WONDERFUL FLORA!
    WHERE CAN GET SOME OF THOSE BEAUTIES?
    THANKS FOR PASSING ON THE SITE.
    HOPE ALL IS WELL IN THE CRAMER HOUSEHOLD.
    I LOVE YOU GUYS!

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