Can I throw castor bean (Ricinus communis) on the compost?

Rising Sun, IN

I've researched this a bit, but found conflicting information.
I have 3 huge, 3 medium, and a dozen small castor bean plants. I hate to have to bag them up for the trash and would love to toss them on the compost pile.
I can't decide if the ricin in the plants would affect next year's vegetable garden. Could the veggies take up the toxin via roots? I don't want to accidentally make anyone sick of course by creating some sort of ricin-infused tomatoes.
I'm also concerned about any contact with the compost, I try to make myself wear gloves but I'm known to go barehanded most the time. (And barefooted too, for that matter! I'm an ol' hillbilly at heart!) I don't have any problem touching the plants but of course they are intact so I don't know if there would be a problem once they are chopped up.
Any thoughts on this issue?

Mid-Cape, MA(Zone 7a)

Poisonous Varieties
All parts of the castor bean plant are poisonous. The University of California Cooperative Extension recommends that you not use poisonous plants such as the castor bean for garden mulch or compost, while the Chattanooga Audubon Society asserts that small amounts may be incorporated in a larger compost pile.

Ratlover, I grow red castor bean plants every year because they are handsome, tall plants with a tropical look. I too have no problem touching them or collecting seeds, but I think I'll go with the University of California on the idea of composting them. Particularly since my compost pile is not a hot pile and I do use my "black gold" in my veggie garden.

Rising Sun, IN

Hey, thanks for the response!

My pile isn't hot either, I'm afraid. I guess I will play it safe. Such a shame for all that lovely potential compost to not be used! Not worth the risk, though. I have plenty of straw, grass, veggies and other non poisonous fodder to compost for next year.

I went to UC Davis for a year...I tend to respect the UC system so I think I'll follow their recommendations too. Have a great autumn!

North Ridgeville, OH(Zone 5b)

Have you considered burning the stuff and using the ashes?

Glenwood Springs, CO(Zone 5b)


There were castor bean plants growing all along the Santa Ana River, (Southern California) when I was growing up as a boy.We did with them what all boys do, whack them down and use them as weapons! LOL :)

We were however warned about them being toxic. Our parents called them Jimson Weed, (Wrong!). Ricin is however one of the most toxic substances known to man. Please err on the side of absolute caution and pitch them in the trash. I am sure you can find tons of gardening services who would give you all the goodies for your compost pile like I do.


Centennial, CO(Zone 5a)

Jimson weed is Datura, which is also poisonous.

Everett, WA(Zone 8a)

Maybe use them as mulch for bushes. If it's safe enough to grow them, it ought to be safe enough to use them as mulch. (Not that I know anything castor beans, I just hate to waste potential compost.)

It might cut down on slugs and snails.

I would say "mow them into the lawn" or "mulch flowers with them", but I assume you compost lawn clippings and year-end flower remnants.

Rising Sun, IN

Heh does sound like a good way to get rid of snails/slugs!
I'm actually more afraid to use them as mulch since I do have cats and dogs running around, even though I too hate to waste any bit of potential compost.

I've been known to 'scavenge' apple cores, banana peels, etc. from work until I remembered to bring in a canister and train my coworkers to toss their coffee grounds and veg/fruit offings into the can!

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