if your compost pile is getting hot and your worms don't have a escape they will die off. Worms are usually the last step in a compost pile. Once the pile cools off worms move in and continue the process. It is not unusual to find a healthy worm community thriving in older compost piles where there is a abundant food source and ideal living conditions.

Personally I wouldn't buy any to add. But if you dig in almost any old compost pile or manure pile, you'll find compost worms, and probably ones hardy enough to survive your local conditions. If you have a hot compost pile, they'll need to escape to ground or cool bits to survive - usually not a problem if the pile is big enough. No harm in throwing them in, including the ones you've already bought. Obviously they do better in some compost piles than in others.

I find what I believe are red wrigglers (the Cadillac of worms!) in my pile all the time - they find it on their own. Whether they are reds or some other compost worm, they do very, very well in there.

I will tend to toss some that I find into existing compost piles - just trying to help them out.

Red wigglers live in the top two inches of soil, they are not earth worms. As toxcrusadr said, Reds are best for 'worm farming', usually indoors because temps need to stay between 40° and 80° ideally. Worm farming is most often used to compost kitchen scraps, not yard waste. Here's an example of a worm farm setup: - Worm-factory 360 worm bin - I've been using this one for several years. Try it, it's fun. Kids love it!!

IMO, the claim that red wrigglers live only in the top two inches of soil is not relevant in the context of a larger and deeper compost or manure pile. I have found them living and thriving, easily two-three feet down in an above-ground pile, as long as it's compost. Yes, in normal 'soil' (like in a yard or forest) that may generally be true, but believe me, they don't think there is any two inch limit, it's a function of conditions, and if right, they'll go deeper. Whether they are best or better for worm farming indoors is a separate question - they can and do live outdoors in piles quite well.

This discussion is getting confusing because there a many different types of earthworms adapted to different habitats and sources of food. Red Wigglers (Eisenia fetida or Eisenia andrei) are used in worm farms because they do well in shallow bins and thrive on kitchen scraps. This is "green" or high nitrogen material, from a composting perspective. They are unlikely to survive in your average garden that has hot summers and cold winters.

Lumbricus terrestris (a.k.a. Canadian nightcrawlers in the US / common earthworm in the UK) are the worms found in garden soil. They can handle wide variation in temperature and will bury deep into the dirt if necessary to avoid the extremes. They prefer decayed vegetation, often more on the "brown" or high carbon side. They thrive in cold compost piles, decaying leaves, and wood chips.

So get a worm bin for your Red Wigglers. And if you have a compost pile outside on the ground you don't have to do anything. Once it leaves it's hot phase, the common earthworms will find it.

Well stated Richard. Thanks.

@Richard, redworms and other compost worms live in the wild as well, and not just in compost bins. I can state for a fact that some can survive quite nicely even in summer and in winter - or at least they exist in compost piles in the winter, either in stasis or by laying their cocoons which hatch in spring. Obviously they need places in summer that are damp and cool enough (by 'going to ground' or whatever), and I won't claim to know how they survive very cold winters (they won't eat much if the pile is frozen solid), but they do. I am not trying to advocate anyone believing that they will thrive in a garden - earthworms really are completely different. But again, I know for a fact they can live in compost piles, and I presume in the wild that they live in leaf litter in forests or something similar. I'm in a place with relatively cool summers and very cold winters, so YMMV - the 'native worms' in any given locale will differ. That's why I say that if someone wants to have compost worms in a compost pile outdoors, the best way to find them is in compost or manure piles. Anyway, putting some in a pile won't hurt, and adding earthworms to a compost pile - well, that'salso not their native habitat, they live in something more akin to soil and burrow, etc.

I agree that you will tend to see many more in an old compost pile. I have 2 piles. One is finished and one is currently going. The old pile, when I took a fork to it, was TEEMING with red worms. I mean there were so many that it looked like the soil was moving. The newer pile, there are only a few of them here and there. I never added any worms.

I will usually move clumps of less finished stuff with more worms on it to the newer pile, just when turning or when spreading the compost. Not really screening, just some selective shoveling. I like to think it helps but I can't rightly say; the worms like it well enough.

I found red wigglers in my compost pile last year. I didn't have a hot pile, but did turn it occasionally and discovered them then. I was kind of fascinated by them, and hoped not to lose them over the winter. I made sure my pile was at least 3' x 3' x 3' for the winter and a good enough mix of greens and browns so it wouldn't freeze through.

They survived great. I had tons of them once it warmed up. But I ended up spreading that pile (partially unfinished) and put some red wigglers in my new pile. They were there last I checked, but of course not nearly as many.

Earthworms are not a significant part of the composting process anyplace other than a vermicomposting bin. A regular compost pile will be too dry and maybe too hot for those earthworms to live in until it is finished. Earthworms need a fairly moist and cool environment to live in and a properly constructed compost pile will not meet that criteria.

Here are some simple facts about earthworms.

http://extension.illinois.edu/worms/facts/

although no one required to read and learn from this article.

kimmq is kimmsr

There are classifications of types of earthworms, including compost worms, epigeic (top of soil), endogeneic (in the soil), and vertical borrowing. See here:

http://www.earthwormsoc.org.uk/earthworm-information/earthworm-information-page-2

The link above on earthworms does not cover all types of worms - not all burrow deeply. To repeat: there are different types of worms.

Not surprisingly, compost worms thrive in compost (and things in nature like it, like manure) - that doesn't have to be in a vermibin. Some of the epigeic are mostly leaf-litter specialists, might do okay in some compost situations.

As for 'a properly constructed compost pile' will not be moist and cool, that's your definition of properly constructed - people can do compost any way they like. In some environments and circumstances, moist and cool might be the appropriate or only way for them to work.

Well said armoured. One thing I would add is that compost 'finishes' over a period of time - decay happens on a curve with a long tail, if you were to make a graph. Compost is not working one day and 'finished' the next. And the long tail happens well after the hot phase, if there ever was one. Worms can move in as conditions are appropriate, at any time after the pile has cooled.

You guys probably already know that, I'm stating it for other readers.

They may or may not be major degraders at that point, I don't know. But they are doing something, if they are in there. Having said that, I tend to use my compost rather rapidly - that is, it's never there for a year, more like 6-9 months tops from the initial start of a pile to using it. Some people go a year or even two (which I think is too long, personally, I'd rather put it to work sooner). In any case an old pile like that can have worms in it. Leaf piles which are slow anyway (they really DO take a year or two) will have worms in them. Basically I don't think it can be said that worms in a pile means there is anything wrong with the composting process.

I live in a colder climate and piles generally take longer. That said, I've seen worms move in quite quickly after (possibly during) a hot (or at least warm) phase. But then, my piles probably aren't 'properly constructed'. They do love cold piles, to be sure.

I'm convinced they do contribute quite a lot to breaking down materials, but of course will depend on a lot of factors. There's also a lot of evidence that compost worms play other roles, too - aerating the pile, and spreading/multiplying the microbes and food web population. Plus, i"m lazy and happy to have them do the work.

Anyway, everyone can do what they like. But there's nothing wrong with worms in piles, they probably help (in some cases, anyway). And the continuing confusion with earthworms - the burrowing type, not to get caught up in terminology - needs to be avoided.

Can't speak for others, but here in the PNW redworms will indeed self-populate a cold compost bin if food and conditions are ok. I had a 2'x2'x4' high black plastic compost bin that I used to throw all my kitchen scraps into. After about 2 yrs of use (without ever having to empty it) I discovered it to be teaming with redworms in the top 6-10" ! Never added any worms, so they must have just found their way up and in through the open bottom.

That's how I first got started on this whole vermicomposting thing. Made a couple of wooden bins and used the worms from the original bin to get them started. Been loving it ever since.

Harry