Big clumps of worms in compost (especially around the lid)

[Russel Sprout]

Hi

I opened my compost bin (plastic type) the other day and there were huge amounts of worms congregated on the inside of the lid. So of them were in big clumps - the size of a fist. I'd estimate in total there were maybe 6 large handfuls of worms.

Unfortunately I didn't have my camera to hand that day. I went back a few days later and there were a lot less, just the one large clump, so I took a photo of that and will attach below. But bear in mind this is maybe 15-20% of what was there on the previous visit.

I should add that this is a resting / full bin and nothing had been added for a month or two. I do get worms around the lid on my "in progress" bin, but nowhere near to that extent

So...

Is such a huge amount of worms normal?

Why are they all hanging around the lid like that?

Does any of it tell me something about what I'm doing right or wrong with my compost?

Many thanks

[Marb67]

I get this too, especially round the lid much much more. Worms are a healthy sigh otherwise they wouldn't be there.

[Nicos]

Well, they look healthy.
The only time I see clumps of them here ( in the soil) is during a drought where they clump together to retain moisture.

My gut feeling is that could there be something slightly not ok for them with the compost?
maybe too wet…maybe too acidic and it’s breaking down?Have you treated your compost to anything different previously?
Also, if I recall correctly, Autumn and Spring are breeding times for worms. Have you seen any side by side?

Just a few thoughts buzzing around in my head…

[ameno]

That's normal. I find it's usually a sign the compost is ready, so I suspect it's the worms trying to leave to look for more food (compost worms eat decomposing matter; they're not the same as the ones you get in soil).

[Nicos]

^ ^^^^Interesting to know that ameno- thanks.
Mine are open compost bays so I don’t get to see things like that.

[mothhawk]

I agree with Ameno. They are brandling, aka tiger worms and thrive in decomposing compost, and prefer to be near the surface, so they won't delve down and out of the bottom of the bin through the soil to find another. Shake them off the lid into a compost bin that is still on the go

[Penellype]

I sometimes get large numbers of brandling worms congregating around the lid of my hotbin if it has got cooler for a bit and then suddenly warms up. I tend to scoop them up and put them in my wormery.

[Marb67]

I sometimes scoop them up gently and disperse them in the garden soil or large container that I will grow runner beans in the same soil every year. The worms add fresh nutrients for next season. I also add chopped up organic matter that they can drag into it.

[Andraste]

Apologies for necro-posting but I'd be interested to know how your worm situation is now Russel Sprout

I've not had this experience in a proper compost bin so my two pence may well be worthless but when we kept a wormery they only tended to clump like that if they weren't happy about something. Too hot (but I imagine that's unlikely outside in December), too wet or something acidic like a lump of decomposing orange. If you're still having issues I'd be inclined to mix through some browns (e.g. shredded paper/card) which should redress the balance.

[Russel Sprout]

Folks and fellow gardeners - much huge apologies. I totally forgot to come back to this thread to both read the answers and to thank you all for the great replies. Lots of info to digest.

I think wetness is the more likely culprit, as has been suggested. I struggle to get a decent heat going in the colder months. But my compost is usually a bit on the wet side which is something I need to address. In fact, there are other things I need to address too in order to make the most of my compost making, which can be hit and miss. I love doing it though, and so when time allows I'll do some reading up and perhaps return with questions to discuss anything I remain uncertain about.

That being said, the compost was pretty much ready when the worms were behaving like that, so perhaps ameno has a point and their time there was spent so they were moving onto to more bountiful environs. I like that idea!

Andraste - no need to apologise; I appreciate you taking an interest! Not too long after posting, they seemed to disappear. I had shaken a fair few of them into the current "on the go" bin. Perhaps the others found their own way without my help.

Thanks again