vermicomposting, composting with worms, is different then traditional composting and requires some study. The link below is for a site maintained by people that learned about vermicomposting from Mary Applehof from whom I first learned about it.

Here is a link that might be useful: about vermicomposting

600 Litres comes out to around 21 cubic feet I think. Sounds like this is probably a digester, rather than a larger composting bin. A digester is often thought of as easy way to slow or cold compost.

I think you need to step back and learn a bit more about the various types of composting before going any farther.

Eisenia Fetida, the main composting worm, have many names, one I think is the tiger worm. If you want to make small amounts of compost indoors with worms, that is vermicomposting. If you want to make larger amounts outside, that is another type of composting. If you are interested in speeding things up, that would be called hot composting. Adding composting-type worms is unnecessary for outside bins.

In the fall I have oak, maple and sweet gum leaves drop. In the right weeks I FINELY shred the leaves (4 times with mower, or once with chipper/shredder), and use a mesh bin 4'by8'by 24" or 30" high. The core temp heats up to 130 to 150F and composting speeds up. Still, it is a few months before I consider it finished compost.

Can't get any easier that that. If you have not read the short FAQ articles in this forum, and the Vermicomposting forum, do so.

I have a worm composting business so I am pro-worm. If you are just leaving the contents to break down and you have a way for excess moisture to get out and air to get in, then the worms will work well. Otherwise, they will be compost. If you know any horse farmers, see if they have older piles of manure and they will probably have red worms available for the taking. Otherwise spend a couple of bucks at a bait store. I wouldn't suggest buying a pound of worms to add because you don't seem to be in that big of a hurry and $25 - $40 is a lot to throw into a compost pile.

Put coffee and tea grounds in your compost pile and the worms will come. That, to a worm, is like vodka to an alcoholic, can't resist.

I sometimes see requests and offers of worms on freecycle.com. I have on a few occasions had people come and root through my (usually cold) compost and collect a dozen worms to take home.
I have a pretty lazy compost set-up and the amount of worms that accumulate over most years is amazing! Nancy

I overwinter worms in compost and add fresh casting with cocoons year around to compost after it is passed high heating. I am covinced they improve the compost.

Adding worms to a compost bin seems to be just one more extra thing to manage to me. There is enough work to do in my garden I don't have to add another job. I've never added worms, nor seen them, in my compost over many decades of composting. I have seen many, many worms when I dig in my garden tho. I encourage their proliferation in their natural habitat which is in the soil in my garden. To do this I use no chemical fertilizer, bury raw compost between plants, and use mulch. When the weather/temperature changes they can move to where it is more comfortable for them. During cold winters they survive several feet below surface in the heavy clay. As soon as the temperature warms I see baby worms under stepping stones which is apparently a warm worm hatchery. I have so many worms in my garden that in spring there are flocks of robins feasting. This is a good thing because it shows nature at work and keeps things balanced. There is, apparently, such a thing as too many worms so I don't mind the robins taking some. I'm quite sure there are more worms living *in* my garden producing valuable castings than could ever live in a compost bin or pile. Guess I could say my entire large garden is a vermicomposter and my worms probably produce tons of castings.

I believe in keeping things simple which is why I'd never add worms to a compost bin.

I agree totally with luckygal. If the conditions are right in your compost for worms they'll find their way there. If they are not right any worms you add will either die or emigrate.

I cold compost and get a lot of worms if there are plenty of fresh kitchen scraps in the heap. Once they have decomposed the worms disappear.

Thanks to everyone who has replied - your input is greatly appreciated.

Just for the record, I do have a wormery which was set up several months ago and seems to be working quite well. The compost is a separate issue and since I started on it late in the season it was not possible to get the ideal mix of green and brown material. I had quite a lot of sawdust, wood chip and hedge cuttings but not enough grass, along with some tree leaves. I also borrowed some partially composted material from the scrap heap in my motherâÂÂs garden but this would have contained a lot of weeds. My garden soil is poor and I wanted to speed up the composting in order to improve it for this year. The first bin was filled about November and more bins were added in recent weeks. The bins have not heated yet and there does not seem to be much activity, even in the one that is about four months old.

I am not a gardening purist and will settle for a reasonably good outcome, even if things are not done according to the textbooks. Therefore, I have taken a chance and have added some tiger worms to each bin. If the experiment is a success I will be delighted and if it fails it will be a learning exercise.

I will eventually empty the bins, one by one into a concrete bay where the material can be more easily mixed and if the worms are still in a good mood, they may like this environment a bit more. If some or all escape to the garden they may do some work in there too, even if they are not the right species for the garden.