This blog is about my garden located in Melbourne, Australia, where summer heat and long periods without rain can make gardening a challenge. It is the gateway to a series of my blogs showing you how I deal with these conditions....John Ashworth 22/04/2017.
use the Berkley (University of California) method of making compost.
It has 3 main features which separated it from cold composting
A minimum cubic metre (1000 litres) of mixed organic waste is required to generate enough internal heat to quickly decompose the composting ingredients.
The heat generated by thermophilic microbes in the centre of such a heap kills plant pathogens and unwanted weed seeds.
The compost needs to be maintained in an aerobic state for at least 18 days for it to hold a temperature of between 55Cand 75C.
The speed of this process, and the way pests are removed suits my garden very well, but a cubic metre of waste is barely practical, and is certainly not convenient in a small garden like mine, so I have adapted the technique to suit a smaller batch of about 400 litres.
In the typical cubic
metre compost heap, the outer layers don't reach the required high
temperatures, but they do provide insulation so that the centre of the
My design effectively replace this outer layer with a 120 mm thick layer of expanded polystyrene foam. It enables me to process a much smaller volume of compost (about 400 litres).
maintain thermophilic activity the compost must be aerated every 2
days, and I do this by moving the bin to a new location every 2 days and
throwing the compost from its original location through the air (to
aerate it) into the bin in its new location.
mimic the insulating effect of the outer layers of a cubic metre
compost heap a much smaller batch (about 400 ltres) can be satisfactorily
processed using a home made insulated bin.
To maintain the required temperature, the bin must be insulated with 120mm thick polystyrene foam in the walls, base and roof.
bin's construction allows the walls to be easily split into two
segments each comprising 2 wall panels. The roof and base are very
light, and its easy to dismantle the bin into its component parts to be
throwing the compost through the air from the old pile into the bin in
its new position, the compost is aerated and mixed thoroughly. The aim
is to keep the compost temperature in the range 55C to 75C, and I use a stainless steel thermometer with a 500mm probe to monitor the heap's temperature.