Some background to the experiment
I first heard about bio-fermenting while staying on a permaculture farm in Costa Rica, Finica Luna Nueva. I listened fascinated as our tour guide, and farm owner, explained how they re-engergised the soil without having to use mountains of compost and animal manure. They of course have these things but it isn’t enough for the whole farm. Being a permaculture farm they wished to bring as little material in from the outside. “Permaculture integrates land, resources, people and environment through mutually beneficial synergies – imitating the no waste closed loop systems seen in diverse natural systems”. Luckily I help out with my friend Matt’s small East London allotment, not a whole farm! The soil is not great, a heavy clay, with layers of new material we have added, so the plants could do with a boost. I love the idea of working with nature to make something more than the sum of its parts.
Some of the science behind bio-fermenting
Using the natural microbes on the organic material (leaves or manure) the mixture will ferment in aerobic conditions (without air) to release chemical compounds and minerals. This process makes the compounds more available to the plants roots than just putting the organic material straight on to the ground. The minerals will also stay in the soil for longer, instead of being washed away in the first rain shower. The other ingredients give the microbes food, and encourage them to breed. If you are able to test your soil, see what minerals it is deficient in, then you can add some of these minerals to the bio-ferment as well. Something I hope to be able to try out in the future. The Permaculture Research Institute have a great video on their web site showing how the professionals, with a lot more soil to fix, make a bio-ferment. For more information about Permaculture from a UK perspective, events, courses, and local groups, check out the Permaculture Association website.
The recipe is taken from the farm in Costa Rica, simpler than the online ones I found. I wanted to keep this first batch small in case it all went wrong, so we used;
- 500g each of; leaves (not fresh and a little decomposed), molasses and wheat bran.
- I got the molasses and wheat bran from my local health food store, and the leaves from the edges of a wild space near the allotment.
- We also added 20g of an organic compost accelerator for an extra injection of microbes.
- Then we poured in 5.5 litres of water. My online research suggested that 4.5 litres (3x the mass) would be enough. We decided to add a bit extra as it seemed a little too dry.
- We then gave it a good mix and sealed the lid on the air tight fermenter with bubble airlock. The kind you use to make beer. It will stay in a shady place for 2 months. Hopefully after this time we will have a rich anaerobic plant food. It will be strained (the remaining matter will go on the compost heap), aerated and diluted. This will then be sprayed onto the plants to give them a boost of nutrients and good microbes.
See my short video blog of Matt and I making the ferment.
In two months I’ll let you know how we got on. Hopefully we will have succeed in breeding anaerobic bugs in the right quantities. Or we will have bucket of stinky mess!!