Compost in barrels – composting in barrels?

What is compost anyway? Can you throw some veggie scraps and dry leaves in a barrel and call it compost? Will appropriate composting processes occur in the revolutionary new composting device that is a barrel with some holes drilled in it?? The answers to all these questions and more below (sort of), but first I’ll update on what’s been going on around the HCC heap.

Some people might tell you that composting is easy and compost doesn’t smell. While those things are true, they come with some caveats. I like to keep this blog light and to celebrate all the good things coming out of the HCC but it’s not always sunshine and things smelling like roses. On and off this summer the HCC heap has been releasing some unpleasant odours and my poor neighbours have been bearing the brunt of this. This is a very serious issue and I need to manage it otherwise the HCC heaps will need to relocate. That’s not good as I know that the current location is very convenient to many members. And I’m very committed to the idea of dealing with these waste materials in our own local community. It works, we just need to get a few things right.

No meat and cheese please!

The main thing that results in odours in the heap is when the wrong stuff goes in. Mostly members are putting the right stuff in the buckets (although I have seen some fish, cheese and even a whole piece of steak once, these are all no no’s). But sometimes even the right stuff can go a little wrong, when a bucket is left to sit too long. Any break down of materials in the collection buckets is not composting, it’s much more likely to result in fermentation or anaerobic decomposition. If veggie scraps in particular start to break down in the buckets they release a lot of water. That water can be handy in the compost heap (saves me having to water the heap) but in the bucket it sinks to the bottom and gets pretty gross if it doesn’t have access to air. Fear not though, I will accept a bucket in any state! If the occasional bucket gets forgotten about and left to rot then I can mix its contents into the heap and the ‘baddies’ producing the smells will quickly be vanquished by the change in conditions and hopefully also overwhelmed by the ‘goodies’ (the aerobic decomposers). But if too much stinky, slimy material comes into HCC then I might need to take additional measures.

Making microplastics, these were all collected on the tarp and sent to landfill though, unlike the good stuff that will now go in these barrels

I tried out a new tactic lately with the help of some barrels that I had been meaning to experiment with anyhow. These barrels were only going to be discarded before I rescued them so it was worth a shot putting them to work! I’ve actually had them in mind for a while, they may help extend the HCC network by acting as mini composting hubs. In the meantime, I transferred the stinky part of the compost to them and then also added fresh scraps to the barrels to give the main compost heap a bit of a break. This worked insofar as the compost in the wooden bays returned to the pleasant, earthy smell that it should be (as noted at the open day last weekend). But it did mean a lot of extra (and extra heavy) handling. And while the barrels were great in terms of containing any smells generated, they also amplified them due to not enough fresh air entering the barrels. So they are definitely not a long term solution, nor as good at composting as the wooden bays that Scott built.

luckily the pitchfork fits in, just

The barrels did generate a little heat though, when filled with a combination of half-composted materials, some dry leaves and some fresh scraps. So some composting was probably occurring. In which case, can they perhaps work as effective composting mini hubs, or at least appropriate holding bays for scraps?

Introducing the ‘host a barrel scheme’! The idea is to supply a barrel (with air holes for ‘breathing’) with a layer of dry leaves in the bottom, followed by a handful or so of half-composted materials to activate. Then the barrel can have scraps added to it gradually over the course of a month from a single, or a few households. This will work best if the scraps are layered with dry leaves (I should be able to supply these too, if needed) and the whole barrel can occasionally be rolled on the ground to give it all a good mix. One thing that could be a problem is if the barrels get overfilled, mostly because then I won’t be able to lift them!

I’ve since learnt that giving the barrels a gentle kick to roll them along is much more ergonomic than pushing!

Possible benefits of the scheme include getting the scraps into a compost-like environment before they have a chance to ferment on their own, as well as being easier for collections logistics, as I should only need to collect the barrel once a month. And this would also mean that they could operate in areas outside of the current collection area, maybe even Belconnen or Gungahlin! (South side would still be a bit of a trek, sorry).

So if you’d like to host a barrel send me a quick email and I can fill you in on the full details. In the meantime I’ll be maintaining the main heap and keeping it smelling sweet. I’ll keep an eagle eye out for any meat or fish (and leave it out for the currawongs) and if there is slime in the bottom of a bucket I might have to drain it and dry the contents before adding to the heap! Oh and I’m not going to put the larger buckets out front anymore, to encourage more frequent drop offs for those who drop straight to HCC headquarters (my place).

As usual, plenty to keep me busy. As long as I can keep composting then I’m happy with that 🙂


HCC – for small buckets of scraps with nowhere else to go

HCCers meet Cass in Watson! Cass is a member of the HCC ‘targeted demographic’ as she lives in apartment with limited space for gardening or otherwise playing with soil etc.

Before I was in my late 30s and could finally afford to buy a house (with dual income, thanks Scott!) I lived in apartments/flats for years. Or rental houses, where I frankly wasn’t all that interested in setting up infrastructure such as a compost bin. So, I understand the desire to be responsible and sustainable with waste yet not really have the room or resources to do so. Cass was happy to join the HCC and know that her small volume of organic wastes were going to a better place than landfill.

That raises another pertinent point: Cass fills one of the small (2L) yogurt buckets each week. When I started the HCC some people didn’t think I would be interested in their scraps because they only generate a small amount. In fact the opposite is true! I’ve also had places like cafes and organisations offer to give me their kitchen waste ‘because they generate a lot’. I’ve been meaning to write a blog piece about how the aim of the HCC is not actually to produce compost… that’s merely a bonus. Suffice to say, the main aim is to avoid the generation of greenhouse gases from organic wastes and I think the best way to achieve that is to get as many people on board as possible in terms of being responsible with their waste. Some people are still not aware that sending our kitchen scraps to landfill is not the smartest move. But if each household can begin to consider alternatives then we can develop new systems around changed habits. Larger composting operations may be able to collect bulk food scraps from cafes and offices etc. and that is probably commercially viable to do so, especially as more organisations realise that that is a cost that they are willing to bear in exchange for other benefits. Collecting small bucketloads from households is a bit trickier. If enough people get on board, and follow my (very cheap!) suggested donations then it might become financially viable for the HCC. In the meantime I will continue to do what I can with the resources I have available 🙂

One other fantastic thing about Cass is that she is so committed to the composting cause that she is willing to talk about it with others. I didn’t actually realise that it was Cass’s word of mouth that led to another lovely member joining up (hello to Jen in Downer). Cass also remembered that although she uses the 2L buckets, I’m always a bit short for 3-5L buckets (perfect for larger households) so she made sure to nab an olive bucket from work and saved it from recycling. I’m always on the lookout for 3-5L post-consumer buckets (with lids) so thanks very much Cass!

So to anyone who is thinking of joining the HCC, especially if you live in an apartment or unit with limited outdoor space, and even if you don’t think you generate all that much in the way of scraps, you too could be cool like Cass!

A cosy autumn morning for the second HCC open day

Just last week I was joking with a workmate about how ‘it never rains in Hackett’ but I guess the joke was on me this morning as it rained this morning only during the HCC open day and not later in the day like the weather man said it should (although if we get some more after I write this that would be tops).

Regardless, it was a lovely cosy morning and the soft rain did not put me and other motivated compost lovers off. Everyone who came by got a good run down on the operations of the HCC, whether that was by way of my informal speech or private compost tours and demos. One of our newest members, Ingrid in Downer, even got stuck into a bit of pitchforking! and then long-time scraps donor Wen Wen followed her lead. Amazingly, Scott even did a little compost shifting 🙂 Ingrid and Maryann were impressed by the heat in the middle of bay 1 and thought the compost had a lovely, earthy aroma.

I told everyone about my plan to invest in an e-bike (probably a pedal-assist cargo trike…) to make the Saturday collections in Watson and Downer carbon neutral. An important announcement was the new ‘host a barrel’ scheme. I’ll write more about that in a follow-up blog post soon. New member Kaye signed up on the spot and gave me 3 months payment (‘suggested donation’) up front. Every little bit helps to get that bike, and hopefully a chipper somewhere along the line too. Apart from raising revenue I also suggested other ways that people can help the HCC. It’s prime time for leaf collection starting now, so thanks to Peter for dropping a bag off to get the donations started. Claire in Hackett thought she might be able to help with washing some buckets (I’ll rinse them first) and Katy in Gunderoo (she drops off scraps direct to Scott at their work), offered the services of her partner and his ride on mower! (to process leaves).

Overall there were lots of discussions about getting the word out about the HCC, how composting actually works, how to have more compost heaps to service other areas, particularly apartments, and what to do with the lovely compost when finished. Oh, and by all accounts lots of coffees and cups of tea were imbibed 🙂

Thanks to Katy, Scott and Ingrid for taking photos! Although the light rain showers might have scared off a few punters hopefully the pics show potential new members what a bunch of lovely people we are. Next time they can all come along and learn just how easy taking care of your kitchen scraps can be with the HCC.

Tying out the compost selfie station the day before









On the agenda

Me doing all the talking while Ingrid does all the hard work

Even spiderman got into some composting..


Keep on turning for best compost and lowest greenhouse gas emissions

Some people may be surprised by the quantity of kitchen scraps that the HCC heaps can process. The scraps from over 50 households are added to the heaps every week, along with a bunch of dry leaves to balance out the carbon and nitrogen. This amounts to a large volume of material, bay no. 1 can easily fill in a busy weekend. Yet as long as I keep the whole thing turning we will not reach capacity and there is still room for more scraps. That is because it only takes about a month for those fresh scraps to be ready to use as compost in local gardens. How are the HCC heaps so efficient? It’s about keeping the mix right but it’s also due to the hours I put in each week turning the heaps.

Once bay no. 1 is full it gets turned over into bay 2. Bay 2 can sit for a day or so and will reduce in volume a little as all of the critters, fungi and bacteria do their thing. But it won’t be long till I disturb their world once more by turning over bay 2 into bay 3. And once bay 3 is full? Do I move it all over into bay 4? Not yet! Nope, I get a bit more of a workout and actually start shifting bay 3 material back over into bay 1. Sometimes this feels like I must be a sucker for punishment, so it was great to find this recent paper backing up why I go to the extra effort.


In the paper, by Yang and others, they showed that mixing in mature compost is very beneficial when composting kitchen scraps. Not only are you providing inoculum of the good bacteria and fungi onto your veggie scraps and leaves/dry carbon materials, you’re also avoiding the generation of greenhouse gases. That’s great! as that is exactly the main motivation behind the HCC. All of the organic wastes that currently go to landfill release greenhouse gases when disposed of in that way. As opposed  to composting with plenty of available oxygen the scraps in landfill instead ferment and produce methane and nitrogen gases, very potent greenhouse gases. Compost heaps can also generate these gases, especially if they are not well managed. If a compost heap is producing unpleasant smells then it is releasing quite a lot of methane also (which has no smell). What the study by Yang and colleagues showed is that not only is turning of the compost needed, but also adding mature compost into the mix is very beneficial. They found that almost 70% of the greenhouse gases that would otherwise be released could be avoided by mixing in mature compost.

I already knew that the extra turning was a great thing to do but it’s lovely when some scientists have put in the work to quantify just how great an advantage it can be. One of the other benefits of shifting bay 3 material back to the start of the process is that I get to retain and manage moisture levels. Once a nice thick layer of fresh veggie scraps has been added to bay no. 1 (10-40L or so) I pile an equally thick layer of somewhat matured compost from bay no. 3. As the veggie scraps start to ‘cook’ in the middle of the heap condensate travels upwards and helps to re-wet the compost from bay 3 which was starting to dry out. It’s a rare occasion that any part of the compost heap needs to be watered.

I think there are also microbial ecology benefits of keeping the compost on the move. When it comes to the bacterial part of the community the interactions are certainly on the micro scale, with different sub-communities living on a fraction of banana peel as compared to another community living on the bread crust a centimeter away. ‘Challenging’ these communities by frequent mixing keeps the overall community diverse and active in many different ways. Let’s hope someone carries out some quantitative science on those fascinating aspects soon!

For now, I’ll get back to turning the compost 😉