Worm composting update: Inching closer to closed loop

Worm composting

An update on my foray into worm farming, 3 months in. Plus, a progress report on my attempt at a closed loop composting system in my small apartment.

The worms get a real home

Back in November, I got worms. While they were doing okay in my makeshift setup, I’ve since updated their digs to a commercially produced worm farm, a secondhand find acquired via the good folks at the Sydney Sustainability Centre.

This proper worm farm is larger than my quick fix of a reusable bag inside a milk crate, so eventually I should end up with more worms and more composting capacity.

The worm farm comes with several stacking trays that all have drainage holes on the bottom. They sit overtop a non-draining bottom tray with a tap.

The worms are actually in the middle tray, munching away.

I started with just one draining tray over the bottom tray. You only need to add another into the stack when the tray where the worms are fills up.

A month on and they’ve already filled one tray to capacity, so I’ve added another on top. I lined the new tray with a cutting of a hessian sack that was part of last year’s halloween costume. Worms can move through this loosely woven material just as easily as I can party in it. I’ll let them finish their meal in the bottom tray before I add anything up top though.

worm farm stacking trays
The trays are the same dimensions, an optical illusion makes them appear different.

When they do migrate up to the new tray, it’s time to harvest the castings as rich compost to use in the garden.

Maintaining a worm farm over summer

The worm farm is pretty low maintenance, except on those scorcher days.

It was 38 degrees last week and 35+ earlier this week. This might be normal for the outback, but it’s hotter than usual for Sydney. And as we’ve come into summer I’ve noticed my south facing patio actually receives a lot of sun. I keep the worm farm in what has become the only sheltered area of the patio.

On those hotter days, I’ve been adding a palm-sized block of ice right into their bedding to keep them comfortable. I check them to see that the bedding (a mix of dirt and coir) is neither too wet nor too dry. So far, maintenance has been simple.

Happiness is a black sludge

In doing a general check of the worm farm, I had a peek at the catch tray and noticed sludge, liquid and a few worms.

There is no way to make this look better than what it is. But trust me, it’s exciting!

The liquid could simply be a result of the ice I’ve been adding that has melted and pooled rather that true worm ‘pee’, but the castings are the real deal: worm poo. I added the half trowel-full to the base of my two raspberry bushes.

Would you be surprised to know that the worm composting set up doesn’t smell at all?

I drained the liquid and left it to aerate for a good while. I diluted it with water and gave it to some daggy ornamental plants as an experiment. I’d like to research the use of this liquid a bit more before using on food plants.

Closed loop composting in an apartment?

My goal is to set up a closed loop system where my kitchen feeds my Bokashi, my Bokashi feeds my worms, my worms produce fertilizer for the garden, and the garden feeds me. And then back go the scraps through the compost system.

Closed loop apartment composting

Why bother? Curiosity partly. I do have places to drop off solid waste from the Bokashi, so it’s not like I’m stuck. However, in my strange visions of the future, we all have some growing space (like oh say, the swaths of dead lawn surrounding my apartment building), and we don’t need to rely on vehicles to get the nutrients from one place to another. So I want to get the hang of the nutrient flows and reduce my overall external inputs and outputs. Build resilience. I already don’t have to buy any herbs – except cilantro, to my ongoing dismay.

But these are early days and I haven’t yet fed them any fermented waste. The worms are, however, already producing useful fertilizer for the garden. It’s going kitchen -> worms -> garden.

I’m okay with this. It actually makes most sense to feed the worms as many scraps as possible directly. It’ll give me more, better fertiliser, faster, and I can use Bokashi as an overflow for the stuff worms don’t like to eat fresh from the chopping board, like garlic and onion, or the cooked leftovers from making broth.

Besides, I can always bury the Bokashi into a trench in my back bed, donate to a buddy or dispose the solid waste into the food scraps bin I discovered in our building. Turns out my building is part of the Randwick Council pilot program. Go figure. I could put my scraps directly into this bin, but what fun would we have then?

Randwick's Food scrap recycling program

Right now I have a full bin of Bokashi that I’m leaving as long as possible to ensure it gets broken down enough for my wriggly friends to feast on.

Free range v. farmed worms 

Some of you may be wondering about my partner’s ‘free range’ worms released into our back garden bed. I’m not saying his worms are weird, but one evening I found one that’d climbed up an eggplant seedling. I regret not taking a picture.

buried bokashi

There were also heaps where I’d buried a full bucket of Bokashi into a trench in the back garden bed. This nicely proves that worms do like Bokashi, which I sort of already knew. Since my own numbers are low, I stole some and added them to my farm. It was a crime of compassion. They will be guaranteed a good feed every couple of days at the farm.

That’s my worm composting update, nearly 3 months in. I’m not ready to add ‘Worm Farmer’ to my CV, but I’m mastering the basics. Do you compost with worms? How is it working for you?

Bokashi + vermiculture = Zero Waste composting

How do Bokashi and vermiculture work together? Very well! Read on for how I’ve incorporated worm farming into my apartment composting regimen to create a zero waste composting system. 

I got worms.

Actually, my partner got worms. He ordered 1000 red wigglers from the council. The worms are for composting, or vermiculture, and the local council subsidizes them as well as various composting equipment to encourage home composting.

One of the reasons councils are taking this approach is to avoid the steep levy increases that are the byproduct of landfills reaching capacity in the Sydney region. Yep, trash is expensive to truck around to hours outside the city. Maybe we should make less of it?

They came in a plastic bag with a hole poked into it inside a cardboard box.

Why worms, why now?

I’ve wanted to try vermiculture for a while, but limited space and harsh elements in our last place meant sticking to un-screw-uppable Bokashi method composting. We recently moved to a place with a larger and more sheltered outdoor space and I had been thinking again about getting worms.

My partner is normally tolerant and supportive, but not necessarily enthused about compost, so this worm purchase surprised, delighted and confused me. Then I found out he wanted to set them free in the open air garden bed on our patio.

Intervention time.

My philosophy is that if you want people to board Spaceship Earth, you don’t always be telling them they’re wrong. In the end we made a compromise wherein he let 250 worms go free range, and left me to care for the 750 that remained. Is this preparation for having children, or what?*

But where will they live?

Since he ordered worms but no worm farm, I assembled a temporary structure for them with the essentials: darkness, moisture, drainage, and shelter from both wind and sun. What this means in practise is an upcycled reusable plastic mesh bag sitting in a salvaged milk crate with cardboard around the sides for protection. Just call me McGyver.

worm farm hack
Needs must.

This will have to do until I find a second hand worm farm or give in and buy a new one. I’m kicking myself for not taking the one I spied on the nature strip some months back. It’s not hoarding if it’s eventually useful, right?**

But I’m not giving up my Bokashi bin. I’m going to use both. Because while there are advantages and disadvantages to both, they actually work best together.

Bokashi v. worm farms

Let’s start with the fact that I heart Bokashi. It’s easy and did I mention, next to impossible to screw up? It takes just about anything, thrives on neglect and can be done inside your apartment. Bokashi is ideal for people who want to start composting in an apartment and need something low maintenance..

Worm farming is slightly advanced, in my opinion. You need to keep your new pets alive and comfortable, which means considering their habitat and diet. Worms are basically gluten free raw vegans who love coffee. A little more effort invested to accommodate them will reward you with gardeners gold – worm castings.

Worm treats.

Which method to choose? If you regularly kill houseplants, go with Bokashi. If you feel confident, try vermiculture. And if you have the room and the inclination – do both. Why? First, let’s get pedantic.

Bokashi is not really composting

Bokashi is not composting in the traditional sense, mostly because when you empty the bin, it still needs to process in the ground or a compost heap before you can use it on plants. So while I call Bokashi bin contents ‘compost’ for simplicity’s sake, it’s not quite the same thing as what a proper compost system produces. It’s more like pre-compost.

Burying the Bokashi bin contents. Mix in and cover with soil.
Burying the Bokashi bin contents. Mix in and cover with soil.

Worm castings, the solid waste produced from worm farms, are actual compost that can be used directly on the garden. If you don’t have or want a garden, don’t worry, they are easy to give away – just find a gardener nearby. The reason gardeners love worm castings is that when worms digest food, the process results in better nutrient bioavailability for plants. Which means healthy, productive plants and more food from the kitchen garden.

vermiculture in focus
Reg wiggler worms in a thin layer of compost, pre-feed.

Fun fact – there are many animals that help to compost, including soldier flies and salamanders (sort of). Why is worm farming better known? My guess is that worms> flies for most of us.

Benefits of a combined Bokashi + vermiculture system:

Back to why I’m going to keep my Bokashi bin along with starting vermiculture.

Learning by doing

We moved recently to a place with a larger outdoor space, so we’re not being forced to pick one system. I’m keen to know more about worm farming in general and the best way to learn is by doing, seeing and experiencing.

Better soil

Since we’re still south facing, my plants can probably use all the help they can get to grow lush and strong. Healthy plants start with healthy soil. Worm farms produce better fertilizer. This is a vote for the worms.

Landfill diversion

My primary motivation to compost has been diversion of material waste from landfill. Bokashi lets me divert the most, since worms don’t like citrus, onions, garlic, spicy food, cooked food, meat or dairy, all of which happen in my household. This means the Bokashi bin remains a key part of my Zero Waste practise.

Managing volume

I have yet to see how much volume the worms can handle, but since I make most of the food we eat at home and from scratch, we produce a decent amount of organic food scrap (even when taking pains to avoid food waste). The worms will get what they like best, the Bokashi bin will get the rest plus any surplus volume, and eventually, the worms wil get the pre-digested Bokashi contents (see my next point).

Moving toward a closed loop system

The best reason of all to use a Bokashi bin and a vermiculture system for composting is to move toward a closed loop system, which is what Zero Waste is all about. Instead of taking the Bokashi bin contents somewhere offsite (via the compost exchange) I’ll be able to feed them into the worm farm, and then use the worms’ output to feed my own plants. Worms will eat the stuff they typically don’t like, but only after a bit of fermentation happens in the Bokashi bin. This means a thriving kitchen garden without external fertilizers, and the scraps from the food I grow can go back into the compost – full circle.

Next up, aquaculture?***

Now your turn….

If you want to get started, look up your suburb via The Compost Revolution, a council sponsored initiative throughout Australia that subsidizes the cost of composting equipment for residents. Discounts of 25%-100% on retail costs are available.

Not sure about Bokashi? Have a peruse through my bokashi posts to see what I compost with this method and ways to dispose of the solid waste that results (if not setting up a dual system like I’ve just described).

Happy composting friends.

 *I’m not referring to the worms
**My infamous dry wit. Did you know I’m hilarious? Not as hilarious as my cousin Shelley though.
***Not kidding

My first compost exchange

Compost exchange Sydney

I recently started a compost exchange.

Very few councils in the Sydney area offer curbside food scrap collection, making it tricky for people who live in apartments to compost at home, for lack of a convenient drop off spot. They will, eventually. In the meantime, I’ve set about solving a problem I have and suspect others might too.

I thought it would be difficult to recruit people to take organic scraps from strangers based on the yuck factor, the potential for gardeners to want to avoid contaminants, or feel burdened. I was surprised at how easy it all was to get a number of initial responses from community gardens and some individuals.

My first exchange meetup

I posted my suburb and need (dropping off) to get things going. C responded quickly and lives close by. We arrange the drop by private message.

When I meet C, she is the perfect host. I ask her if she’s heard of the Bokashi method of composting, and she laughs and tells me she knows all about it and it’s fine, and to come on to the backyard where her composter sits.

C’s garden is pure magic.

My eyes must have gone wide, because she starts to explain what the different plants are and what they are for. She points out a tree here, a bloom there, and exotic sounding herbs. I am introduced to pomegranates, sandpaper figs, elderflower, pineapple sage, butterfly bush, kumeras, lemon myrtle and tree tomatoes.

Tom-AHHH-toes she says with a laugh at the way I pronounce tomatoes. Neither of us is originally from Australia.

I could have lingered for much longer. I wanted to soak it in, take pictures, write it all down.

But back to the reason I was there. I add my bin contents to her regular black compost bin where it will transition from anaerobic to aerobic. C adds some leaves and branches on top for a balance of browns. Soon the worms will move in to feast on the pre-digested matter.

She tells me to come back whenever I need to. I leave with a large handful of branches and herbs.

I gave her my organics scraps, and she gave me her time, her space, her knowledge (and a giant handful of garden bounty). It worked better than I expected. That was a few months ago now, and I’ve since been back.

Just as healthy soil is a rich, diverse community, so too is our human one. Will you join?

What I compost using the Bokashi method

Apartment composting using the Bokashi method is flexible and convenient because it can handle a wider variety of food scraps than some other forms of compost.

Here are the basics materials that go into my Bokashi compost bin:  
  • fruit and vegetable scraps (seeds, skins, etc.), including citrus
  • eggshells
  • coffee grounds
  • cooked food (such as the scraps from making broth)
  • meat and fish scraps (including smaller bones)
  • paper products (napkins, paper towels, newsprint, masking tape)
  • tea bags (except synthetic bags, which I avoid)
  • bread
  • dairy
  • flowers
  • Small pieces of wood, such as wooden skewers, and handles from bamboo toothbrushes.
What don’t I compost?
  • bio plastics. I avoid these wherever I can.
  • large bones

Bokashi vs worms

I choose the Bokashi method over a worm farm for a few reasons, but chiefly because it is simple to manage and explain to others, because it has fewer no-nos. Example: Worms apparently don’t like citrus or onions, of which I am a frequent eater. Interestingly though, when I bury my Bokashi at my sister-in-law’s place – citrus, onions and all – the worms get fully amongst it. Maybe no one told them? Have a peek at some before and after shots of the Bokashi compost method to see.

If you’re interested, you can learn more about why I choose the Bokashi method for composting in a small apartment, and what you’ll need to get started.