I remember when I was a child, my parents had a massive compost heap. It was located between the garage wall and the neighbour’s wooden fence. It was around 4m x 8m, easily 2m high. It usually had thick black soft and warm compost in there – in fact, we used to love jumping into it from the garage roof. Thinking back, my dad must have spent many a man-hour “feeding”, attending and turning the heap, but I wasn’t aware of it. However, I never recalled them ever having to buy any compost or any fertiliser. That heap fed a very lush garden, quite a handful of fruit trees, some vegetables, roses, flowers, grapes and more. So I knew what compost should look and smell like…
When we did the initial layout of the Homeland vegetable garden we did one thing right. We placed the compost heaps near the vegetable garden. This was merely by coincidence, but it was a blessing in disguise as over the years it has saved us many a long walk. A lot of our compost materials either come from the vegetable patch or the kitchen. Our compost heaps are nothing fancy – just solid 2m black garden stakes driven deep into the hard ground, wrapped with chicken wire on three sides to create three side-by-side “cages” of about 3m x 3m each. We add to the compost heaps in a rotational fashion filling up one heap at a time.
However, we did one thing wrong, very wrong – we placed it on the easement strip very close to the huge eucalyptus trees on the neighbouring schools property. In winter, that wouldn’t really matter, but in the harsh dry Victorian summer that heap just turns into dry “stuff” which has a dull brown colour and no value to any plant.
Right at the start, we also made a second big mistake, but we didn’t really have another option at the time. As we removed many eucalyptus trees on our side of the fence to make space for fruit trees, we chipped and mulched the eucalyptus and added the leaves and small twigs into the compost heap. The net effect was like adding a heap of salt to an already dry piece of jerky. The heap just dried out more.
As part of my effort to feed the compost heap and keep it rich and full of nutrients, I would jump over the boundary fence of our property into the next-door property’s horse paddock! I would take two buckets by hand and proceed to collect Ricky’s droppings! I wish Ricky was a cow rather than a horse, that would be better manure, but you’ve got to work with what you have… Anyway, at least it adds an essential element. But even the horse manure is too dry and I find I have to soak it in buckets of rainwater and then slosh it out over the heap.
Another element I would have liked to add is moved grass! However, one of the challenges on a small acreage is that you mow the lawn with a ride-on lawnmower, which doesn’t pick up the clippings. Those clippings would have added much needed moisture to the heap. The weeds from the vegetable patch and the kitchen scraps just don’t contain enough moisture to make up for the problem of too dry compost! So, I’ve been making a point to occasionally mow with the hand mower so that we get clippings to add to the compost heaps.
Back to basics
I have always focussed much on compost ventilation as an important component of a successful compost heap. But after two years on non-productive compost heaps, I revisited the reading material on compost heaps. It was then that I realised not all compost heaps are created equal. What works in humid Queensland won’t necessarily work in dry Victoria. I quickly figured out ventilation isn’t our problem – with our open chicken wire sides and the harsh winds we get, we probably have too much aeration. Everything just dries out. Our heaps were not wet enough and they weren’t getting warm enough. If we could get the moisture right, the heat will hopefully increase too as those little mechanisms inside there start doing what they’re supposed to do.
Upon further analysis, it also seems we weren’t adding enough brown materials to the heap. So every once in a while, typically when I have a lot of weeds or clippings to add, I would tear up some cardboard boxes and put a layer of that in. We also have a great relationship with The Little Teapot in Lara, where we get all their coffee grinds, and with Bowside Café in Bellbrae, where I sometimes get coffee grinds on my way back from surfing at Bells. These all go into the compost heap. I have read somewhere that adding coffee grinds to your compost will result in a “racier” garden. There are quite a few slow growers in our hard dry clay soil to which I wouldn’t mind giving a caffeine boost in order to wake them up a bit!
I have also started to cover the one heap we’re not currently adding to with the old straw we used to mulch vegetable beds or the roses, so that it can help to contain some of the moisture, much like the mulching of a vegetable or flower bed.
However, the biggest brain wave came when I had to replace a broken water distributor on our grey water system. As part of that project, I diverted a thick 25mm irrigation pipe to the compost heaps (a good 50m away). It’s quite far, and it consumed quite a length of quite dear irrigation pipe, but now we have drip irrigation pipes running in-between the layers of composting material and we have a thick stream of water guzzling into the top of the active heap every fourth cycle of the grey water system. Now if that is not enough moisture, then I don’t know!
We also do further tweaks to the compost heaps on an ongoing basis:
- At the end of winter, I use all the valerian I have left over from protecting plants against frost, mix it in huge buckets and slosh it onto the compost heap to raise the temperature a bit.
- Whenever I do a heap churn – basically flipping one “cage” of compost over into the cage next door, I add Biodynamic Preparation Balls which I get from Biodynamics Australia. These consist of the 5 solid compost preparations –Yarrow (502), Chamomile (503), Nettle (505), Oak Bark (506), each enclosed in 15g Manure Concentrate Balls and a vial of liquid Valerian (507). They seem to help the process, now that the heaps are moister. Unfortunately though, we always seem to have other pressing things to do, so churning the compost heaps is not high on the priority list. I know we need to turn them more, but it is what it is…
- When we rinse out the buckets used for the coffee grounds or the kitchen scraps bin, all that waste water goes onto the heap. My approach now is that those heaps just can’t be kept wet enough. If I start getting rotten stinking compost, I’ll review that strategy and adjust the water volumes…
On the recent “compost bin cycle change” I’ve actually enclosed some of the sides with some roof sheeting I discovered lying around at Dreamland. I’m doing this in order to try and reduce some airflow and raise the moisture level even more.
Talking about Dreamland – over there we are starting to use a very different approach. As part of the digging exercise, we dug two massive holes – each almost as big as the duck pond, so we want to try composting in the soil rather than above. So watch this space for developments…
Where to start? We are still learning…
- Location, location, location… is so important. Not only for sure for efficient access and ease of working on it (I wish I could get a bobcat in there to flip it over!), but also in terms of the natural elements – especially sun, water and wind, which all affect the temperature and moisture content.
- You simply have to get the mix right between the volumes of decomposing green stuff and nitrogen-adding brown stuff. It’s hard to balance, as we just seem to chuck on the heap whatever is available. At certain cycles, when we have two active bins going, we can balance it a bit better. But the garden produces whatever it does whenever it does it. Fortunately composting is not an exact science – there is a lot of scope for variation.
- As you read up on compost heap “designs” and “approaches”, you will come across many, many different variations on the theme. The crucial step is to filter out the material that is applicable to your region, climate and micro-environment.