Worm Bin Mites

Back in November I wrote a post all about mites (A Mite is a Mite is a Mite? Not Quite). I tried to provide a basic overview of the various types of mites that can be found commonly in your worm bin. I’m not going to add anything more to that discussion today, but DID want to share a cool photo I captured this morning.

I was digging through an older red wiggler bin (the one with the Natura Eco Cloth – which incidentally seems to have completely decomposed!), when I happened upon a old piece of broccoli stem that was totally covered in white mites (which by the way is simply a descriptive name based on their colour – I have no idea what the actual species is). This type of mite seems to gravitate towards moisture-rich foods like cucumber, melons and squash, and can be found to spring up – seemingly out of nowhere – in great abundance when decent amounts of these sorts of wastes are added to the bin.

They are a very slow moving mite and people can sometimes even mistake them for ‘worm eggs’, if they have never seen an actual worm cocoon before.

Anyway, just thought I’d share that. Perhaps some of you will recognize this type of mite from your own bin(s).

9 comments

I just noticed these mites in my worm bit today. Are they a bad thing? Do I need to monitor the moisture? The worms seem happy otherwise, but the presence of an unplanned resident makes me wonder if everything’s alright. LOVE your site, by the way. Thanks so much for sharing your experience and information so freely!

Hi Sally,
These mites aren’t necessarily a bad thing, but if they are present in massive numbers this could be indicative of a more serious problem (overfeeding, excess moisture etc).
I find that these mites absolutely LOVE it wet – and they seem to pop up in huge numbers when I’ve added too much waste – and materials that are not broken down enough for the worms to process them quickly. I now use lidless systems and never see these mites anymore.

Hmmm. I noticed little white specs in my worm bin that are about salt grain size. I thought for a minute that it was just worm eggs until I realized they were movingb and looked like little spiders.
My concern is when I was putting my bin together I needed extra soil for my bedding and my son brought me some. (I didn’t realize he had took it from a plant our next door neighbor had outside) This is not cool is it? Do I need to start over?

Are mites harmeful to humans? I seem to recall when I was in school “scabies” was mites on humans. It caused a rash that was contagious and kids got sent home because of it. Needless to say I am a tad bit “mite-shy”… I have red mights in/on one of my worm tubs. I read where you said that it was because of moisture, yet the tub that has them is quite dry. In fact, I watered it excessively today in hopes that they didn’t like the wet because they definately DID like it dry! (Won’t do that again!)
So, back to the original question, are mites harmeful to us??

Hi Colleen,
There are so many different species of mites on the earth, and yes I’m sure there ARE some that can harm humans, but it is unlikely that they reside in compost heaps (wouldn’t really make sense to hang out there if it’s mammals they are interested in – haha). The common one’s you find in your worm bin certainly won’t hurt you.
That’s interesting re: your mites liking it dry – in my systems they seem to decrease in abundance when moisture is reduced.

my worms have been disapearing but there is not any dried up worms on the outside of my bin they have disapeared in the last several weeks. i have had my worm in my garage we live in colorado so it gets pretty cold at night. we had a heat lamp over them i was a red heat lamp when i would go check them the soil and food scraps were quite cold. i definetly know that there were red wigglers because i ordered them from uncle jims worm farm, i honestly like your site better. then we put them inside and we noticed there were a lot of nats and mites so we stopped feeding them for a while. then when i would check on them there we less and less. so we started feeding them again then i checked again, and it didnt look like the even touched their food. i found one really fat one do you think that the fat one ate all the worms??????

Hi Sam – I am not going to slam anyone here, but it’s not uncommon for batches of Red Worms to include Blue Worms (Perionyx excavatus) – in warmer weather it can be challenging for many worm farmers to keep them out of Red Worm beds. Blue Worms are tropical and perish when temps get cold, so if there ends up being a lot of them in a particular batch of worms you can end up with a much smaller population than you started with when the mercury starts to dip!

Make sure you sign up for the RWC newsletter so I can give you a lecture about worm bin critters NOT killing off worms! haha
(I dedicate some mini-lessons to this topic)
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