Saturday, June 27, 2009

Fun with compost


It was the perfect day for the annual compost harvest here in Amateur Land. Cool and cloudy, with very little chance of working up a sweat. Given that there's always a fair bit of heavy lifting, shovelling, forking and bending involved in my little compost harvesting operation, I couldn't have asked for a more helpfully miserable day. This is a once-a-year job, and it's always well worth doing, as I now have all the compost I could possibly use in a year, and another batch on the way.

Here's this year's batch of sweet-smelling, dark and crumbly compost. It has actually been ready to use for the last couple of months, and I have been using it in the garden, too. But there comes a time each year when I do what I call my 'harvest' of the compost. I remove all the good quality, ready-to-use compost from my efficient tumbler compost bin, and store it in my other, more basic bin, one of those inefficient black Dalek bins.

This photo just barely squeezes in the Dalek bin on the left (and also in the mirror reflection on the right), and the tumbler bin is in the background. All this is hidden from view by a small hedge of murrayas.

Traa daa! The empty tumbler bin. It holds quite a lot (full capacity would fill five or six of the pictured trugs), but its one real design fault is that getting the compost out of the bin isn't that easy. It involves a lot of scooping and shovelling and, towards the end, tipping the bin straight into the plastic trugs. (As my garden is too small for wheelbarrows, my trugs do all the wheelbarrowey work around here. I love them.)

This is the harvested compost from the bins. As well as using this stuff to fertilise garden beds and especially vegie beds prior to planting, I also use my compost as a potting mix 'extender', mixing it 50:50 with a good quality potting mix. As all modern potting mixes are just a glorified and expensive form of compost anyway, adding my rich, home-grown stuff probably improves its overall quality. My other use for compost is when I plant seedlings. After preparing the planting site, I add a good scoop of compost, firm it down, then plant each seedling straight into that. They usually roar away in that rich little environment.

The old black Dalek bin plays an important role here, but it's a pretty hopeless compost bin. Its main role is to be the 'overflow' bin. Once the main tumbler bin is absolutely chock-full in late summer/early autumn, I stop adding stuff to it and let it break down for several weeks, tumbling it over regularly to help everything break down faster. Meanwhile, all the fruit and vegie scraps from the kitchen, plus suitable garden clippings, go into the 'overflow' Dalek bin for however many weeks it takes for my tumbler-bin batch of compost to fully break down.

Today's big harvest operation is laborious, but it's essential. I take all the 'made' compost out of the tumbler bin and set it aside in the trugs. Then I transfer all the contents of the Dalek bin into the tumbler. Then I transfer the made compost into the Dalek bin, which then becomes a mere storage unit for ready-to-use compost. Sounds like hard work, but I try to think of it as good exercise! And for the last few years it has let me both make and store all the compost I could ever wish for.

As you can see in the photo above, one of the magic composting ingredients I have discovered is cheap garden mulch. Every time I add a bucket-full of fruit and vegie scraps from the kitchen, I add a handful of straw mulch. Any old straw mulch will do. Here in Sydney the cheapest stuff is sugar cane mulch. This 'dry' straw balances out the relatively 'wet' fruit and vegie scraps, producing a nice, not-too-dry, not-too-wet, mixture. To further balance out the acidity of the fruit and vegie scraps, I add in a handful of dolomite lime when I add the straw. This keeps the acidity (pH) of the compost somewhere near neutral. You could add shredded newspaper instead of straw, if that's plentiful, but I tried shredding my own office paper and tired of the workload of doing that. Just opening the shed door, reaching in and grabbing a handful from the bag of mulch near the door works a lot better for me!

Another magic ingredient in composting is air. That's why the tumbler bin is so superior to the Dalek bin. Trying to poke a garden fork down into a Dalek bin to give everything a stir is too much hard work even for me, and I'm a glutton for punishment when it comes to composting! By comparison, giving the tumbler bin a spin is easier, although when my large bin is close to full it does take a fair bit of strength to turn it over.

My final 'magic' ingredient in composting is good old garden soil. It's full of worms, microbes and life, and so I usually add one or two scoops of ordinary, fertile, healthy garden soil to help get a batch of compost going.

Hopefully a few of these tips might be useful to someone who's trying to get their composting system working but is finding it hard to get the formula right. It took me several years to get the hang of making good compost, and so it's definitely not as easy as some people make it out to be. But then again, it isn't rocket science either. Just a bit of persistence, adding a steady variety of ingredients to the bin to achieve a good wet-dry balance, plus remembering to turn the heap over regularly, should do the trick.

1 comment:

Bangchik and Kakdah said...

Very detailed and interesting post about composting ... we did open compost by piling up grass cuttings and other biodegradable items... we end up using half-done compost as mulch.

Our attempt at compost tea have to wait till september.

Nice writing indeed

~ bangchik