If you want to make organic garden fertilizer its hard to do better than this rich compost as prepared by the permaculturist Karen Parkin.
We were given this demonstration on composting by Karen Parkin at a recent permaculture design course in Noordhoek, Cape Town, run by Alex Kruger and Tahir Cooper.
As you will see in other articles on hot composting and aerobic composting on this website, for the process to generate heat, you need the correct Carbon-Nitrogen ratio. Karen explained that it is the Nitrogen which fuels the heat releasing reactions. She then taught us via actual practice how to construct a compost heap, with layers of straw, comfrey, manure and kelp repeated again and again, kept neat and square until we had a large cube of compostable material at least a metre by a metre by a metre, which is needed to conserve enough heat within. We then rammed a sharp wooden stick into the heap to see how warm it was. For days it would emerge steaming !
I would like to emulate this process at home. I’ve acquired some lovely pallets which are fastened together with cable ties and lined with the canvas from an old tent that was left on my front porch by an unknown person for some time.
I have neither straw, kelp nor comfrey at the moment, but I do have different kinds of manure, one of the most important ingredients in organic garden fertilizer like hot compost. To supply approximates of the required ingredients I acquired green hedge clippings to replace the comfrey herb, and "poor man’s straw" as real hay can be expensive. I saw that the council had left great heaps of cut grass in roadside meadow in Epping, so I helped myself to nine large plastic dustbin bags of grass.
These heaps of cuttings from the long grass in the meadow contain a large amount of grass and other weed seeds, so I wish to drive the process to be very warm indeed to kill the seeds. Hopefully this will be accomplished by the bags of stable sweepings we fetched from a local government horse farm, containing round horse droppings, wood chips and straw, as well as the large bucket of humanure and the smaller buckets of urine soaked sweepings from our garden. I prepare these by sweeping up the fine broken, dried vegetable material from the paved areas under the trees in our garden.
I fill the sweepings into a ten liter bucket, cover them with a dusting of wood ash and sawdust, and then add urine every day until the vegetable material’s ability to soak up urine has been slightly exceeded. This normally takes several days, especially with two buckets. We were thinking of going to fetch kelp at the beach as we do have a bait collecting license so perhaps this will be accomplished.
The old heap in the first chamber made of pallets is about a
month old and has shrunk to about eighty percent of its original volume,
indicating that it was rather nitrogen rich, because with the perfect ratio,
not so much volume is lost. For an organic garden compost intended for growing leaf vegetables, having a lot of organic nitrogen in a natural form is not necessarily a bad characteristic. Turning of the old heap is long overdue, and I will do this
on Friday and build the new heap in the vacated bin and describe the turning and the building in the next article.