Friday, 10 February 2012

The beauty of compost


I’ve just been out the back of the house on the concrete pad I am trying to turn into a garden and I’ve been stirring the organic material in Darth Vader the compost bin. That’s right. There is now a rotting pile of vegetable matter sitting out back. All week it’s been attracting insects and other unseemly activities like decomposing with all the sticky, sweaty, messy rot that that entails.

That’s one way to look at it.

On the other hand . . .

I’ve just been out the back of the house on the concrete pad I am trying to turn into a garden and I’ve been stirring the organic material in Darth Vader the compost bin. That’s right. There is a finely balanced and infinitely fascinating micro ecosystem sitting out the back of my house and it’s decomposing. And I am beginning to realise that this is a complicated and wonderful process.
Imagine that you are looking at the rainforest 65 million years ago. This is approximately the time the dinosaurs died out and by now rainforests were the most common forest type on earth (http://www.rainforestconservation.org/rainforest-primer/rainforest-primer-table-of-contents/c-age-of-tropical-rainforests ).

Above your head is the translucent green of the forest canopy stretches it arms to the sky and below that, draping down from tree trunks are ribbons of vines brightened by splashes of green trunk-hugging parasites. Further down and ‘strangers’ clench their woody fingers to tree bark, ferns tickle the rooty ankles of trunks and moss holding pearls of moisture creeps over earth and wood alike.

Everything in this verdant world lives and dies. When it dies it falls and it rots and when it rots this is because insects and even tinier life forms are eating and emitting gasses, creating heat. Turning the old forest into a blanket of rich nutrients to feed the new.

This ancient and complex system has continued on forest floors to this day. And it’s very similar to what I am doing at the back of my apartment in the belly of Darth Vader, champion of compost.

When plant and vegetable matter containing carbon and nitrogen is put in an atmosphere where is has plenty of oxygen and water, something amazing happens. Bacteria find food, actinomycetes munch on cellulose, fungi and yeast set to work on the lignin in woody material and protozoan and rotifers in turn eat the bacteria. Don’t know what half those things are? Nor did I thirty minutes ago. Go to http://en.wikipedia.org/wiki/Compost#Micro-organisms and click the links. Earthworms and insects help along the way and after not very much time at all a dark, rich crumbling substance is achieved.

When a compost pile is watered and turned, it decomposes especially quickly. The centre of a compost heap can be 60–70 degrees Celsius, due to the furious energy of the microorganisms breaking it down (I will have to remember not to burn myself).

Here are a few pointers that most internet compost writing seems to agree on:

  • Setting up the compost pile on bare earth is preferable to concrete. I don’t have bare earth so I put quite a large pile of old potting mix at the bottom to line the bin. This had an added advantage because I knew that the material in the pot was full of worms.
  • Make sure your compost pile has adequate drainage.
  • It helps if you monitor the carbon to nitrogen ratio by mixing ‘brown waste’, containing high carbon, (usually woody material although also fruit waste) with ‘green’ waste (usually leafy material), containing high nitrogen (for more info check out http://www.composting101.com/c-n-ratio.html ).
  • Turning and watering the pile regularly speeds up the process by making sure all material in the pile is getting oxygen.
  • Don’t compost human or animal faeces, noxious weeds diseased plant matter. And I won’t be composting meat or dairy since it can attract rodents and other unwelcome visitors.
  • Also, apparently urinating on the compost pile is quite good for it.
The thing I love about my compost pile is the smell. It doesn’t smell rotten, it smells of earth and wood and it’s very rich. It’s as if something primitive inside me knows that it’s good stuff.
For more info check out:
http://www.aucklandcity.govt.nz/council/services/garden/compost.asp

 And I quite liked this too:
http://home.howstuffworks.com/composting.htm

 The Auckland City Council are even offering free composting courses. I might even go to one . . . if I can ever find the time.

 

 

 

 

 

 

1 comment:

  1. A few years ago now my husband a keen community gardener was checking out a seed savers place in Ngaio. In a corner of the garden was a huge heap of compost covered by black polythene. Husband commented on the pile and was told...all those noxious weeds that you can't compost go in this pile. The black polythene heats up the pile so hot that it sterilizes the seeds from the plants....When the pile is big enough etcetc Pumpkin seedlings from the regular compost are planted into holes through the polythene into the weed compost...which has now become a pumpkin patch. If you want to be doubly careful put this patch on concrete or...and here is a nice touch...the iron roof of an old shed for vertical gardening...coz pumpkins can take a bit of room in a small patch...Using this theory you could chuck the weeds on your roof, flick over polythene and grow pumpkins...hehehe

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