Amanda Doofenshmirtz
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Earthworms and tea caffeine

I drink a lot of green tea. Mostly fruity and floral blends. I recently switched from table sugar to stevia. When I remodel my worm bin and get more, i know they are gonna love it. But my genius fiancee just asked me if that would be too much caffeine for such a small organism, and i was unsure. :shock: anyone have any experiences with coffee grounds or tea leaves hurting your worms in excess? I just don't have the heart to "experiment" with something like that without doing a little research first. I love my wormies lol.

Once my old bin is cleaned and fixed, im going to order more from Uncle Jim, fill the bin with moist, shredded newspaper, add tea leaves and some old bread, then top it with a little straw.

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rainbowgardener
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Re: Earthworms and tea caffeine

You are talking about the used tea leaves, after you have brewed them for tea? Just as with used coffee grounds most of the caffeine (and most of the acidity in coffee) is in the beverage. What is left behind is very mild and is fine for your worms. For coffee, somewhere around one-half of one percent of the original caffeine is left in the grounds. I haven't seen the analysis, at a guess it is similar percentage for the brewed tea leaves, but they had a lot less caffeine than coffee to start with.
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Amanda Doofenshmirtz
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Re: Earthworms and tea caffeine

That makes a ton of sense, thank you. I thought that may be the case, but I was not sure.

I have decided to do an independent student experiment to test the effects of caffeine on worms, and I am going to be doing that this summer. I am curious to see if the caffeine may invigorate them to compost faster, but I am not sure. Thanks for the response, I will remember what you said as I build the experiment plan and implement it. And I'll post my data should I find anything cool!

jeff84
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Re: Earthworms and tea caffeine

I don't know for sure, but I kind of doubt that a worms brain is even sophisticated enough to have receptors for caffeine.

xtron
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Re: Earthworms and tea caffeine

don't know about that jeff.. as a kid I picked up worms to sell to fishermen. the best place to find them seemed to be right outside the kitchen door...right where mom dumped the coffee grounds every morning. I think they are subject to caffeen addiction, just like humans. lol

Amanda Doofenshmirtz
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Re: Earthworms and tea caffeine

Sorry I have been away for so long! xtron, that is cool stuff! I was fascinated by your post.

I found a website that can estimate the amount of residual caffeine left behind in coffee ground and tea leaves, and it's pretty substantial. I guess that's why many teas are re-steep-able. (At least the loose leaf teas I buy are, but I dunno about bags, I don't use bags. The Tea Source rules!)

So far, the adults cannot be killed by 400 mg caffeine a week for four weeks. But almost all of the babies died. No threads and very few eggs, some of which were deformed. Just wiped out the babies. My previous caffeine free trials had hundreds of threads after 4 weeks and the 300 and 400 mg caffeine trials had fewer than 20. So far I can say that if you overdose a worm bin consistently with caffeine, you will doom the bin to only last for 1 generation, and then you'll have to get more worms to keep it going. Best to keep caffeinated food waste to ONE AREA of the bin so they can lay their eggs away from the drug. Once they're grown, they don't mind it, but the babies can't handle it.

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Gary350
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Re: Earthworms and tea caffeine

All summer I had a 20 gallon plastic trash can setting under a large shade tree with about 5 gallons of garden soil inside the trash can. Every day I throw kitchen scraps in the trash can that include coffee grounds & a few tea bags. I stir the organic material into the soil then replace the plastic trash can lid to hold moisture. Soil stays moist with the plastic lid, I sometimes remove the lid if I know it is going to rain it sometimes needs a little more moisture. It was about late July when I stirred the soil and noticed it is full of worms. There must have been a few worms in the garden soil when I put it in the trash can, now there is a lot of worms. About Nov I had a pretty nice potting soil mix with 100s of worms I dumped the soil in the garden and covered it with tree leaves. I expect this pile of soil mix to be full of worms this spring. This is going to be my potting soil mix for planting seeds in trays. Coffee grounds do not seem to be a problem for the worms. There is a lot of coffee grounds in this soil mix it feels gritty like sand I hope it is not too gritty for new plants.

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