Vermicomposting: How a DIY worm farm can compost food scraps, paper or a whole kangaroo

Worms. I have several.

I split my time between a small inner-city apartment in Sydney, Australia, and a wild property that was once a farm before it was abandoned in the 1970s four hours south.

They are opposites in almost every way – one booming with the constant noise of the big city, the other moving to the rhythm of the wilderness: kookaburra choruses, deafening cicadas and, at night, the mighty hooting of owls and the gurgling, zombie-like call of a possum. But one thing both properties have in common is that they each boast a crank worm farm. The one on the farm is huge and deals with the organic waste of the entire household, while the one in the city is small enough to fit on the porch and is easy to set up – suitable for everyone.

On the farm, I continued to let nature take its course on the land and use it as a place to hide for peace and quiet. But it’s busy underground. Inside the 4000 liter tank buried on the property is a huge worm colony into which all my sewage and gray water pours. The worms convert the sludge into nutrient-rich juice and excreted castings that are slowly released, filtered into a series of filled porous trenches and then out through the soil into the surrounding forest.

The giant worm farm in the wild has a lid, and it’s possible to vary the worm’s diet a bit from a daily meal of toilet waste and shower water by throwing in compost and weeds, as well as the occasional kangaroo, opossum, or bird carcass I find on the property. My rule of thumb is that if he was once alive, then his final resting place is the worm farm.

When I take the cover off and look into that black hole of decay, I’m always amazed at how quickly whatever ends up there disappears. A dead, 50-kilogram male eastern kangaroo (Macropus giganteus) is barely discernible after a week and invisible to my torch after a month. It’s true that the worm farm is now a multicultural ecosystem that includes frogs, spiders and fly larvae, all thriving in nutrient-rich moisture that would make the Daintree Rainforest on Australia’s northeast coast proud.

And yet, even after more than eight years of being the repository of all things biological—shoveling wheelbarrows full of organic material into the voracious wormhole—its steady state seems to be no more than a quarter full. No matter how much of a dead kangaroo or spotted bird I throw in, I have never smelled any unpleasant odors coming from my worm farm. This is no amateur clockwork operation – every few years the local county council checks that it is officially compliant.

On the day the worm farm was installed in 2018, I was invited by the installer to ceremoniously deposit the worms into their new home – a small bag of tiger worms (Eisenia fetida), a species originally named in 1826 in Europe that has become the international superstars of global composting.

Independent earthworm researcher Robert Blakemore says the species lives in temperatures from -2˚C to 40˚C and can survive the loss of nearly two-thirds of its body moisture and reportedly complete submersion in water for up to 6 months.

He claims that there is no other species on Earth that provides such an important service to humanity, and that a compost worm can supposedly process the equivalent of their body weight in a day. It is not surprising that a dead kangaroo can disappear within a few weeks.

I love the fact that everything that goes into that worm farm is broken down by worms into all the diverse original ingredients of life and then slowly seeps into the ancient red gum forest where it is captured and recycled into the ecosystem. That worm farm is my idea of ​​real pearly gates – through which everything is recycled into immortality. That’s why I tell my children “when I die, let me go” to join all the other life that has passed. The sky for me is to become food for my forest. If I were instead cremated and turned into a handful of faceless dust to be kept in a jar, I’d actually be pissed.

I have an elderly chocolate border collie who accompanies me everywhere as my personal discreet secret service agent. The highest honor I can give him, the surest way to keep him around forever, is that when his day comes, he’ll also walk through the clearing of the worm farm. My daughter is not impressed with the fate that awaits our family dog.

Breeding urban worms

When I moved to the city part-time a few years ago, I brought a bag of tiger worms from the Wilderness Worm Farm and used them to seed a small, commercially made homemade compost bin that I have in my small yard.

My little homemade worm farm is much more intimate and straightforward than the giant one. It is about half a meter in diameter and height and has several vertically stacked trays that can be rotated when the top one is full.

Unlike the worms on the country property, which are meters away at the bottom of a huge dark tank, my urban worms are right where they can be easily observed and are much more interesting. Sometimes I just take the lid off and find myself staring at it meditatively, my face contorted in amazement that the composting process looks so disgusting.

No one wants to see sausage being made and the same goes for decomposition. The first thing you see when you take the lid off my urban worm farm are the squirming tangles of worms. There are so many of them and they’re so twisted that it looks like if I dipped my hand into organic matter in various stages of decomposition, it would be chewed to a pulp in minutes by those filthy piranhas.

All my vegetable scraps, dog poo, dog hair (my dog ​​houses many), eggshells, banknotes, tea leaves, coffee grounds – all organic. Although when Blakemore saw the picture I sent him of the contents of my worm farm, he was a bit concerned about my laissez-faire attitude.

“I see you have eggshells; it’s better to crush them or heat them in the microwave to help break them down, even if they do eventually fall apart,” advises Blakemore. “Ditto fur. Tea bags are my bane, I suspect they’re plastic because they don’t decompose! Also those silly labels they stick on bananas or avocados.”

He also warns that “dog poo is a parasite problem, but many can be created by worms.”

No matter how much I put in my city compost, the worms seem to keep up, but eventually, after many months, I have to pick up the top cartridge, move it to the bottom one, and start filling a new, empty one. When full, the contents of the first cartridge turn into a rich black soil that can be distributed among my plants in the yard.

It’s the great writhing circle of life, a window into the reality that decay is a chilling reminder that we all die and live on a planet where everything eats everything else. The gravediggers of the soil, the humble worms, are the bearers of immortality, the processors of all that once lived.

I think of Blakemore’s admonition: “Everyone should compost,” he says. “There is no reason not to, except for our cardinal sins of ignorance and laziness.”

Things to consider if you want to start your own worm farm:

• Compost worms are commercially available and easy to obtain – the king of compost worms is the tiger worm (Eisenia fetida), originally from Europe, but now found worldwide. While you can easily buy worms, I gave a few friends “starter” colonies – just a small bag filled with worms – from my compost, and within weeks their bins were overflowing!
• You’d be surprised how much waste a worm colony can process even in a relatively compact urban worm farm. They are easy to set up and buy. But if you want a farm suitable for household waste management, you’ll need professional fitters and plenty of space.
• I keep my urban worm bin out of direct sunlight. When choosing an outdoor spot, look for shade, especially if you live in an extremely hot climate. It also never seems to smell – although take the lid off and it looks like something out of a horror movie. But the long and short of it is that it’s not an unpleasant thing to have around.
• My favorite things to compost are utility bills and marketing junk. (It’s best to avoid heavily colored or glossy papers.) There’s something very satisfying about putting things you don’t like in a worm farm and watching them turn to dirt in a week!

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