For the first time in my composting career I've produced a rich, dark pile of beautifully crumbly compost teeming with worms.
On the face of it, this shouldn't have happened. It's in a loose hippo sack in a shady corner on top of a concrete patio – no sunlight, no warmth, no soil underneath. The only reason I put it there was because it's close to the kitchen and relatively out of view.
So how did it work out so well?
Tracing back through the history of this heap might provide some clues. The first thing I did was put down a layer of fine brush cuttings from the garden, to keep the pile free draining and avoid an anaerobic slime forming at the base where it's in contact with the concrete.
Next, my aim was to create sufficient material to spread over an area of approximately 8 square metres of garden which is currently covered in plastic sheeting and gravel: a dead soil in a dead space. Ideally I was aiming to get a layer of compost at least 100mm deep – so that's nearly a cubic metre of the stuff. Living in a small household that's quite a target to generate out of kitchen waste in one year, so I made it my mission to garner as much green waste from any source possible: surplus growth from my garden, weeds from the back alleys (making sure they hadn't been sprayed with herbicide recently), donations of grass cuttings from friends, wood shavings, the ends of compost and manure bags, kitchen waste from my workplace, everything and anything biodegradeable.
As a result, the ambitious size of the heap helped the decomposition process by allowing heat to build up within the pile – in fact once it had all but filled the hippo sack I'd often find it steaming away on even cool mornings when I went to add the latest caddy of kitchen stuff. The other aspect of that is the sheer variety of material that went in maximised the chances of the right kind of micro-organisms being present to set the whole thing off.
Another major contribution came I think from covering the heap with a bit of geotextile fabric which was lying about in the shed. This is permeable, allowing the pile to breath whilst keeping much of the heat in. I also drenched the pile with kitchen waste water every now and then, re-covering with the sheet to keep this moisture in.
At one point I transferred a fruiting body from a fungus found in a nearby grow bag into the compost, hoping rather unscientifically that the spores would find a suitable home in my home-made pile. I don't know if this worked, but I some time later a very active fungus made an impressive appearance in the form of a beautiful toadstool on the top of the heap. It was then that I knew we were heading for success, but I never dreamed that the result would be as opulent as the fabulous earthy mulch I turned over last weekend. I can almost hear the carrot seeds booking their square inch of compost...
One word of warning – on one occasion (and, happily, only one) I disturbed a rat scouting the pile for titbits. Really, it's better to securely sequester food waste in some form of container which can be protected from rats, (though burying 12" deep under the soil is another way to put food waste into your nutrient cycle directly).
Bagging the compost up to transfer to my raised beds last weekend, I found the final proof of the pudding: dozens of seeds germinating – discarded beans, mainly – but among them, a couple of quite exciting chancers: an avocado stone, and what looks like a nectarine, both sending hopeful feelers into the unknown. Happy to help, I pot these into a couple of empty yeast pots, and look forward to watching a couple of new recruits settle in to my indoor jungle.
The lesson for me is that variety really is the spice of the life of a compost heap; in other words, the more opportunities you leave to nature the more chances she'll have to work her magic.
This article first appeared on Simon's website, www.sjw-landscape.org. Simon Watkins is a landscape architect with a special interest in sustainable edible landscapes and is currently studying for the Diploma in Applied Permaculture.