“Why is ‘buying’ compost worms a thing, when they are in my garden? Aren’t they?? And if they aren’t in my garden, then how do I find compost worms in the wild?”
I’ve definitely had wild compost worms show up in my outside composts.
If you make compost piles on the ground, or store large amounts of decaying organic matter – like horse manure or autumn leaves – you’ve probably had wild compost worms eventually arrive there too.
So why buy compost worms, can’t we just collect some worms from the garden?
The simple answer is: if they’re in the soil, they’re not composting worms and so they’re not the worms that will work in a worm compost.
Here’s a more interesting answer to that question.
Science has identified and classified about 9,000 different worms so far. And they’re classified by where they live and what they eat.
Endogeic worms live in the soil and eat microbes and very tiny particles of very well decayed organic matter, and a bit of soil.
Epigeic worms live in the decaying organic matter on top of soil and eat a different set of microbes which are living in and breaking down that organic matter. These worms don’t eat or live in soil.
Only about 7 of those 9,000 identified worms are epigeic worms. And these are our beloved composting worms.
Endo = in. Endogeic worms live IN the soil.
Epi = on. Epigeic worms live ON TOP of the soil (in decaying organic matter).
The epigeic worms are superstars at turning a pile – or a worm bin – of decaying organic matter aka compost into earths best soil builder, fertiliser and pest & disease control
Whereas the endogeic worms have a whole other role out there. They are an absolutely necessary part of the soil food web that exists in healthy soil.
But they don’t do composting.
And they aren’t they right dudes to put in the worm composting system.
Now you know the nerdy sciency part, let’s go hunting for wild compost worms!
We can definitely start a worm farm with compost worms from the wild.
It will a bit take longer than just buying some.
But it’s totally do-able!
Finding Compost Worms In The Wild
There’s 2 ways we can go about this:
- Actively by going out to find them – this could result in a total win on day 1
- Passively by enticing them to come to us – this takes time, maybe up to 6 months
And there’s 2 points we need to remember:
- If we’re going to put our wild caught compost worms into a worm composting system aka worm composting bin, we want at least 500 worms per cubic foot of worm bedding – or they’ll take a looooong time to build up their numbers to a point where your worm compost actually works properly.
Wild compost worms usually look like they’re wild. Skinnier, darker colour, and less abundant than compost worms that hatched and grew up in captivity.
Ok let’s first setup the passive enticement. Then while we wait for that to work, we can go hunting.
How To Call In The Wild Compost Worms
Get yourself an air instrument, maybe a penny whistle or a cows horn pipe, and at sunrise stand barefoot in the middle of your garden and play it until you have at least 500 worms gathered at your feet.
It would be funny and neat if that was a real thing that worked.
There is a thing called ‘worm grunting’ where you hold a length of wood to the ground, which has notches cut out all along it, then rub another piece of wood back and forth over the notches, creating a vibration in the ground.
I’ve seen videos of this being done, and wriggling worms appear very quickly.
But I’m yet to try it myself so I can’t say whether this is effective or not for producing compost worms specifically. It probably is, if you’re in a location where there are compost worms very close by.
Worm grunting aside, let’s make a nice home for any nearby compost worms to come live in.
If there are compost worms nearby, this will work. If it doesn’t work, that’s because there are no wild compost worms in your vicinity.
Which would be a shame, not just for your worm trap.
Once enough of them have shown up, we can move them to the worm compost bin and away we go, worm composting!
We’re going to make a pile of decaying organic matter and we’re going to either make it directly on the ground or in something that is on the ground and has holes in the base.
I prefer something on the ground with holes in the base, to keep the compost out of reach of bigger critters like mice and possums and bandicoots.
Any kind of container that:
- is at least 30 litre capacity (50-100 litres is good)
- you can drill 1/2 inch holes in the base of
- you can leave in one spot on the ground for an extended period of time, perhaps 6 months,
- and that you can close (never airtight) off from other animals normally attracted to a compost,
will work well.
I use old wheelie bins.
You could too. Or you could use a plastic trash can. Or a big storage tub. Or the inner tub of a dead washing machine. Or you could just make the compost pile directly on the ground.
If you use a container, you might want to move it later when it’s time to get all the worms out. So consider that too.
I did this at a much smaller scale once. I used cafe ice cream containers which are 10 litre capacity I think. I drilled holes in the bases, made mini layered composts in each container, and set them in the shade in a chicken coop that had recently been decommissioned.
It worked ok. Not great. The wheelie bins seem to work much better.
But my varying results could be purely about the location and nothing to do with volume.
I don’t know, and it doesn’t matter, this is about having a bit of fun and working with what nature is already doing and seeing what happens.
Set The Worm Trap
Moisture and airflow are essential to the composting process. So in your container drill a heap of 1/2 inch holes in the base and a row of holes from top to bottom on each side.
Place your worm trap container somewhere where it will always be in shade and where it is in direct contact with the ground.
Now fill it up. Make it like a simple but real compost. And use stuff that worms really love to chew on. Like pumpkin and bananas and melons and corn.
Um, worms don’t have teeth.
The way I do it is to layer food scraps (high nitrogen) with shredded cardboard or hay or mulch (high carbon).
Then I give it a big watering, close the lid, and walk away.
I make sure it never dries out, and after maybe 6 weeks I’ll get in there with the pitchfork and turn it all a bit.
Waiting Patiently For The Wild Worms
Once it’s composted down for 3 or 4 months, it will lose quite a bit of volume. And if the wild chaps are nearby, they’ll either be starting to come on in, or hanging about very close waiting for a little more decomposition to happen.
My wheelie bins sit on dirt, in a shed, which is between a house lawn and a paddock. Juice leaking out the bottom is not an issue in my shed, and helps to call in the worms.
And even though it’s just grass grass grass as far as a worm eye can see, the composting fellas do eventually show up.
Err, worms don’t have eyes either.
After a few months, turning that compost over helps us to get a visual idea of how many worms are there. Once it seems like there’s a few hundred, we can go ahead and start moving them to our actual worm composting system.
Or we could just leave this container as it is. Because this is now a worm compost. And if looked after like a worm compost, then a few months after the worms arrival, the whole thing will turn to worm castings.
And can be harvested like any other worm compost. And restarted too.
How To Go Get The Wild Compost Worms
Now that our “bait” is set, let’s go actively searching for compost worms in the wild.
What do we need?
- A bucket with a lid on it (never airtight) and something for the worms to hide in, in it (moistened shredded newspaper is great)
Maybe gloves, maybe a short digging tool, maybe a hat and bottle of water
A mountain of aged horse or cow manure or an aged traditional compost pile or an old pile of lawn mower clippings or even a house guttering full of rotting leaves.
Ok that last location is a bit crazy, but I and a friend have both found compost worms in the guttering of sheds.
What we’re looking for is some kind of pile of decaying organic matter. Decaying being the key thing here.
If it’s a new pile, the worms won’t be there yet.
A pile of horse manure that has sat for 6 months or longer may reveal an absolute bounty of composters!
The compost worms eat microbes that do composting, and horse manure is spectacular in number and diversity of microbes, second only to worm castings.
Maybe your trick could be to buy 4 or 5 of those $2 bags of pony poo on the side of country roads, and empty those bags into a pile at your place.
Or maybe not. There will be an aroma for a few days. Big black flies will come for a few days.
But we could cover the pile. Because we do want it moist – so the composting microbes can do their thing first, and the composting worms can come along next.
I’m semi rural on a couple of acres so it’s no issue for me to make a poo pile. I get that on a smaller block with close neighbours a poo pile may not be appropriate.
Taming The Wild Compost Worms
Once we’ve struck gold with the location, and we are definitely poking around in the decaying organic matter and NOT in soil, we can fill our bucket with our new composting buddies.
On the journey home we’ll make sure to keep the bucket out of the sun. We’re not looking to cook a worm pie here.
Back at home, we’ve already got the worm bin setup properly ready to add the compost worms.
If we are coming home with a bucket full, we can just tip the worms into the worm bin.
If we are harvesting from the baiting container, it’s just a matter of digging around and plucking the worms out – maybe into that bucket with somewhere for the worms to hide – and then putting them in the worm bin.
If you’ve bought compost worms before, you can probably see the difference between tamed worms and these new wild worms.
And as they breed and their young grow up in captivity, we’ll soon have a composting crew just as happy and calm and effective as any we may have paid for.