I’ve used a number of composting techniques over the years, some typical garden cone composters, I tried a hotbin, and until recently I used 2 pallet compost bays, approx. 1.5m x 1.5m x 1.5m. However, I found these a bit too difficult to keep equally moist, and they were also not very well accessible.
Generally, all these methods work well, but as I was filling the compost bins gradually, they did not go through hot composting process that is required as part of the soil food web training.
The benefit of hot composting is that it deals effectively with any potential human pathogens and weed seeds: Beneficial bacteria who have the right food supply for their needs multiply rapidly and are highly active, which generates the heat. After this, other organisms in the soil food web proliferate during a cool-down resting period, including beneficial fungi.
Earlier this year I filled the pallet compost in one go, lifting lots of moistened compost ingrediens out of the blue, which gave me repetitive strain injury in my elbow, and I was not able to do much heavy lifting for months. (I know, what does that say about my fitness and strength!) Need to do more graded exposure to hot composting!!
In an ideal world, I would have liked to go with a Johnson-Su’s compost bioreactor process. However, this does not fulfil the process and methodology required by the Soil Food Web school which I am focussing on right now. Nor does it deal effectively with weed seeds or pathogens. The soilfoodweb end results might however, and I will test this at a later stage, if I have sufficient materials without weed decontamination.
I was looking for a solution that:
- Matches my ergonomic requirements
- Matches my growing space and is easily portable
- Can be used for both the processes required by the Soil Food Web school and Johnson-Su
- Has a volume that I am able to fill without having to set aside a lot of storage space for dry materials, which would reduce the growing space I could use
So, in an attempt to introduce biocomplete hot composting to my life, I opted for this framework.
I changed to a new system, that might even move around the growing space. At the moment, it sits right in the middle of the plot (pictures to follow!). And with 500 litres volume, it is more manageable for me in terms of my building strength, and in terms of gathering sufficient materials to fill the containers at once.
It is near enough my mini vision for a future compost bioreactor trial. To save time, I purchased the frame and some velcro fasteners for quick assembley. Wire or string that does not decompose readily will do just fine.
I am really happy to have 360 degree access to the composter to make turning it more easeful.
It is built directly on the ground, as my sandy loam soil is not going to create water logging and thus anaerobic conditions.
Getting a thermometer that is long enough remains a challenge, for some of us solved by soil food web practitioner and innovator Daniel Tyrkiel with a 3D-printed, stainless steel thermometer.
In the meantime, I purchased some 20” thermometers on ebay, supposedly from within the UK.
They came from elsewhere, could not be calibrated, and one was more than 10 degrees wrong. Returning them was not possible – I ended up with defunct thermometers and out of pocket.
This 500mm long thermometer may bridge the gap on small-scale, this Agreto temperature probe seems sturdier and is available in different lengths. If you test it out, please share your feedback in the comments.
And as I need to get my composting going asap, beggars can’t be choosers. This reportedly has problems with condensation getting into the display but be otherwise functional. Well, I’ll just have to leave it in the shed and just measure when I am on site, and hope for the best. Bit tricky to calibrate, as the scale stops at 90°C!
Daniel, can’t wait for your thermometer!
Several buckets are needed, and the ratio of different compost ingredients is measured by volume. The Soil Food Web school recommends 5 gallons, which is just under 19 litres.
Any between 15-20l should be fine, as long as they are all the same. If there are any catering facilities near you, they may be able to leave some out for you.