I had a worm bin for two years, and recently I went to feed them one week and they were there. I went to feed them the next week, and they had disappeared entirely, with no trace of a body anywhere. I checked the pH of the soil, and it was 8.4. Is there any other reason the worms might have disappeared other than the pH was too high, and how can I adjust the pH so I don't hurt my new worms? Thanks for helping me!

Ariane Osterwald



We asked our favorite worm expert Amy Stewart (author of The Earth Moved: on the remarkable achievements of earthworms) for her advice on this one. Here’s what Amy had to say:

I am so sorry to hear about your worms! Without knowing a little more about the conditions the worms were in, it's hard to say for sure what happened. The most important conditions for keeping worms healthy in a bin include:

Moisture--The bin should be about as damp as a wrung-out sponge.

Temperature--Red wigglers, the most common composting worm, prefer temps in the 50°F-70°F range. While they can tolerate temperatures outside that range, they won't reproduce as quickly, and extreme heat or cold can kill them.

Food--They need a steady diet of organic matter. If you've had a bin for two years, you probably already know what to feed them, but the basic rule is to treat them like vegans: no dairy or animal products, and no vegetable oils, either.

pH--They do prefer a neutral pH, and it sounds like the enviornment they were in was pretty alkaline. Since most kitchen scraps, coffee grounds, etc. that people feed worms are more on the acid side, I wonder if something got into the bin to push the pH up to that point.

Regardless, the worms probably died (as opposed to escaping)--the body of a worm breaks down very quickly after it dies which is why you didn't see any bodies. My suggestion is to empty the bin, wash it out, and start over again with a shredded coconut fiber bedding, which you can buy in compressed bricks at most nurseries. Introduce a new batch of worms to the bin, let them settle down in the coconut fiber, and keep them covered with a thick layer of shredded paper. After a few days, add a little food--maybe a banana peel--and gradually start adding as much food as they can consume without it getting moldy or rancid.

For more on worm composting, you can check out my book and download my worm composting handout here: www.amystewart.com/info.htm.

And always feel free to stop by my earthworm blog, Worms of Endearment, where I post worm-related news and answer questions: www.wormsofendearment.blogspot.com

All best,




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