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Bokashi composting

Bokashi was developed in Japan and literally means ‘ fermented organic matter’. A fermented wheat-bran mixture called Compost-Zing is used in a bucket system where food is literally pickled. The final product has a slight sweet/sour smell.

The System

The Bokashi two-bucket system consists of a few simple elements. Two buckets are required, with one nested on top of the other. The top bucket has a tight-fitting lid and holes in its base to drain to the lower bucket. In addition, there is a bag of Compost-Zing made from wheat-bran and untreated sawdust that has been mixed with molasses and water and effective micro-organisms.

You can make your own system as long as it is airtight. Old Paint buckets that have been cleaned out work. Drill holes in the base of the top bucket and sit inside the other one. A good seal is very important.

The benefits

The benefit of this system is that you can add products such as meat and fish, which are discouraged in the usual compost due to vermin and odours.

It produces a compost product within 2-4 weeks after being buried rather than 3 or more months in a compost pile. No space is required as fermentation takes place in the bucket, which makes it ideal for small houses, apartments and schools.

Buckets can be kept indoors as the smell is inoffensive. It keeps food waste out of the landfill and it is good for your plants adding beneficial vitamins to the soil.

Getting started

Sprinkle a layer of Compost-Zing in the base of your bucket (1 tablespoon). Add a layer of food and remember to break it into small pieces. Once you have a layer of about 3cm, add another handful of Compost-Zing. More may be used in summer than winter.

Push layer down gently to remove any air, as this is an anaerobic process (a potato masher is ideal). It is best to minimise opening the bucket to avoid excess air. Air can be easily removed by pressing down on the centre of the lid. Close the bucket lid tightly.

Drain any liquid that forms at the bottom of the bucket every 3 - 4 days. Dilute as required. When the bucket is full, close lid and keep in a warm place for about 10 -14 days.

When the food waste smells like pickles, it is ready to be buried in the garden. Plants can be put directly into the soil after 10 days.

Foods you can compost

All food waste which is well-drained which includes:

  • fresh fruit and vegetables
  • prepared foods
  • cooked & uncooked meat and fish
  • cheese and eggs, coffee grinds, tea bags
  • wilted flowers

Foods you cannot compost

  • liquids such as milk, orange juice and oils
  • meat bones
  • shells from seafood


For Bokashi stockists, refer to the Council's subsidy coupon. Download the composting subsidy voucher or call the Council on +64 3 546 0200.