What is Bokashi?
‘Bokashi’ composting is a method of quickly breaking down organic food waste into high quality compost. It uses easily cultivated micro-organisms already found in the soil to ferment food waste under anaerobic conditions (no oxygen)
- Food waste is gathered and combined with a fermented 'starter' bran in an airtight bucket that contains a straining system so that any liquid in the food stuff can be easily drained. This liquid when diluted is also used as fertiliser, it also has other uses such as drain cleaning.
- The full Bokashi bucket is left to ferment for a period of at least 14 days.
- The fermented contents of the bucket are then combined either in planting beds or containers with an equal amount of ordinary soil and covered with mulch and left to sit for a further 21 days.
- The resulting soil can then be packaged and sold as compost or used for immediate planting.
Important features of Bokashi are:
- It is a fast and efficient method of turning organic waste into high quality compost i.e. good soil
- It is easy, requiring only the mixing of organic matter with the starter bran and keeping it in airtight conditions
How to Make Bokashi Compost
- Sprinkle a small amount of activated bran in top bucket.
- Place food scraps in bucket.
- Sprinkle more bran lightly across scraps
- Compress firmly with potato masher or similar
- Place lid on bucket & ensure it is airtight.
- When bucket is full leave aside for at least two weeks.
- After this time bury the contents in a garden bed making sure to mix well with ordinary soil and cover with mulch. Leave for another 2 weeks and then plant.
Making the Bokashi Bucket
The size of your bucket will depend on how much food scraps you have every day.
Ten and twenty litre buckets are available at bargain or hardware stores also, soap powder and other cleaning products are often bought in these large buckets, hotels and restaurants that buy gravy and other sauces in bulk may have empty buckets. Most important is that the two buckets fit tightly together and that the top bucket has a lid that will seal tight. The key to this whole process is NO AIR in the bucket.
The tap can be purchased from any hardware and costs about $5.00
In one bucket using a normal drill bit put a scattering of holes all around the base, this will allow any liquids in the food waste to drain into the lower bucket.
In the other bucket, depending on the size of the tap you have purchased you need to use a spade drill bit and gently put a hole as low as possible to the base on the side of the bucket. Fit the two buckets together and they are ready to use.
Burying the Bokashi mix
The best outcome after the 2 weeks fermentation period is white mould covering the surface of the bucket contents. Sometimes the white mould is not there but as long as the contents smell sweet the process has worked. If there are maggots in your bucket and the smell is unpleasant it means that air has got into the mixture and allowed the maggots to multiply. This can sometimes be remedied but covering the contents with another layer of bran and resealing the lid. However, it is probably best just to bury the contents and leave for a longer period to break down completely in the soil
Making Bokashi Bran
There is no one right way to make Bokashi Bran, a google search will reveal a lot of information. My method is as follows:
Firstly it is necessary to cultivate Lactic acid bacteria or indigenous micro-organisms. This is mixed with Molasses to feed the bacteria and diluted 1/10 with water when mixing the bran. Instructions can be found in The Handbook of Korean Natural Farming by Dr Cho.
A variety of carbon sources can be used to make the Starter Bran. In Asia, rice hulls are used. Here, we use flaky bran, short cut oats, micronized barley or a mixture of cut lucerne, oat straw and bran. Spent coffee grounds are a useful additive. I sometimes add kelp or seaweed if available and any stale flour, yeast or oats from the pantry.
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