We have a new composting system, Bokashi, and our head gardener Jan has kindly written a blog for us, to talk all things food waste!

Adventures in composting.

Here at The Homestead, we continue to endeavour to be as sustainable as possible. In the garden, the aim has always been to make as much compost as we require to grow the vegetables which end up on the menu.  While many people might see weeds, grass clippings, vegetable peelings, cardboard boxes and fruit peelings as waste, as a permaculture designer, I simply see an under utilised resource.  The principle ‘Produce no Waste’ was at the forefront of my mind when we built the composting bays as part of the overall design.

Despite my long experience as an organic gardener and obsessive composter, the lesson I learned last year that was that we filled those bays quickly, but that the composting process was taking much longer than I had expected.  It was clear that we needed a better solution.  We had to bring in stable manure (which I prefer to avoid, due to the risk of herbicide contamination) to fulfil our needs as we created more growing space. Additionally, slow composting food waste has a tendency to smell and attract flies, and this was far from ideal.  I needed a way to make the compost turn around much more quickly.

After a discussion with Peter, I suggested we try using Bokashi as a method for speeding things up. I had been using this method myself for around 20 years at home on a small scale and wondered if there was a way we could use it here but on a much larger scale. We decided to give a try.

Bokashi is a Japanese word meaning ‘fermented vegetable waste’ and has it’s roots in both Japanese and Korean agriculture. It relies on introducing beneficial bacteria and fungi into an anaerobic environment, which pre-ferments the organic waste, before it goes either into the compost bays, or alternatively into the soil directly.  It then breaks down rapidly once exposed to the air and creates a nutrient rich compost in a very short time.

Bokashi bins are available to buy, but they are only quite small, for domestic situations. I put my designing hat on and asked my partner to build me a couple of super-sized Bokashi bins from spare wheelie bins.  Peter bought us a large bag of Bokashi bran, which is treated with a microbial starter culture, so that we could start our experiment.

To make Bokashi, the bin is filled in layers, with a handful of Bokashi bran sprinkled every time vegetable waste is added. There is a mesh bottom, which allows any liquid to drain from the waste, which we collect as a liquid fertiliser, via a tap in the base of the bin. Once the bin is full, we cover the peelings with plastic, weighed down with roof tiles, to exclude the air. This is then left for three weeks while we fill the second bin, to give the microbes time to work their magic.

The bin is then emptied, ready to be refilled. The vegetable waste initially does not look very different, with just a fine layer of white mould on top and with a slight smell of pickles. We have used this first batch as a layer in the bottom of our potato trenches. The next batches will be added to the compost bays along with weeds, torn up cardboard and grass clippings, where it will act as a compost accelerator, hopefully allowing us to make our compost much more quickly.

In my experience, pre-fermenting vegetable waste using the Bokashi method, not only speeds up the composting of food waste, but also creates a much more biologically active compost, which increases nutrient levels and improves the structure of all soils.  Yes, there are some set-up costs and you do need to buy the bran to add to it, but the benefits seem to outweigh this.

Anyone who worries that food waste might attract vermin, or has previously struggled to make compost at home should consider trying this method.  So far our experiment seems to be providing the solution we had hoped for and we hope to be able to make sufficient compost this year for all our needs.

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If you are keen to learn more about gardening, then please do keep in touch! We will be working with Jan to offer workshops throughout the year, with our next one being all about planting a cut flower garden of your own. Head to our events page to secure your place now.