composting: Part II

​This is the second blog post in a three-part series which covers three different composting systems.

To recap, there are three main ways you can compost your waste:

• Composting bin
• Bokashi
• Worm farm

Each system operates differently.  In my last post on the subject of composting, I focussed on composting bins.  In this post, I will explain how Bokashi works.

Bokashi
As the name suggestions, Bokashi was developed in Japan.  In summary, it is a fermentation process that helps break down food waste much quicker than usual.
Bokashi consists of multi-layered bins which fit inside each other.  It has an air tight seal.  Bokashi is an anaerobic system.  No air should get into the bins.  Bokashi should be stored in a warm place, out of direct sunlight.  In mild climates, you can keep Bokashi in a shady spot outdoors.

Unlike composting bins, Bokashi takes only green waste.  Do not include any brown waste in your Bokashi.  To recap, green waste is organic material that is full of nitrogen.  Green waste is normally soft, fresh and moist.  Examples include food waste and green lawn clippings.  Brown waste is organic material that is mainly carbon. It is dry, brown and brittle and therefore takes a long time to break down.  Examples include paper, cardboard, brown lawn clippings and autumn leaves.  You can add the following to your Bokashi: fresh fruit and vegetables, prepared foods, cooked and uncooked meat and fish, other food such as cheese, bread, coffee grinds and tea bags and wilted flowers.  Do not add liquids such as milk, orange juice or oils, paper and plastic wrap and large meat bones.

Add some “sprinkle” to your Bokashi.  Sprinkle is an inoculant made from beneficial microorganisms, a bit like a yoghurt starter. It contains sawdust and molasses.  Sprinkle stops the Bokashi from smelling by fermenting it like a pickle.

Keep a small food waste container in the kitchen for your food scraps.  Chop waste up into small pieces.  Drain off any excess liquid.  Spread the Bokashi sprinkle on the bottom of your Bokashi bucket.   Add food waste once or twice daily to the Bokashi bucket.  Add 1-2 tablespoons of Bokashi sprinkle per 6 cm layer of food.  Ensure you squash down the food to push out the air as you go.  This helps to get rid of the air.  Close the Bokashi bucket lid tightly after use. Drain off liquid from the bottom bucket at least every 2 to 3 days.  When your bucket is full, close the lid and keep in a warm place, but out of direct sunlight.  Leave for about 10-14 days.  Don’t forget to keep draining off the liquid.  The food waste should smell like pickles and will develop a white mould on top.  This means the system is working well.

During the Bokashi process food waste ferments and often produces a juice. The amount and colour of the liquid depends on the type of food you have put in the bucket. Fruit and vegetables may release more liquid while other foods may release none at all.  The liquid fertiliser can be used in the home and garden. Pour undiluted juice directly into your toilet or down your shower or sink drains to help keep them clean.  Dilute the liquid at a ratio of 1:100, so 2-3 tablespoons per 5 litres of water. Apply this to the soil or the base of plants to help keep them healthy.

The solid end product can be used in the compost bin and garden.  Dig a trench in your garden as deep as the Bokashi bucket and twice as long as a Bokashi bucket laid flat.  Distribute the fermented food evenly along the trench.  Mix the food waste with the soil.  Cover with at least 50-75 mm of soil (if the soil is dry add water so composting can take place).  After 3-4 weeks your fermented food waste turns into excellent compost and you can plant directly on top of it.  If you can’t be bothered to dig a trench or you don’t have space in your garden, you can add the solids to your compost bin as a “green layer”.  Simply spread it out and cover with lots of “brown” material.

This post was based on information provided on the Compost Collective’s website.  For a comprehensive guide on how to Bokashi, visit https://compostcollective.org.nz/bokashi/. 

Composting course
The Auckland City Council runs a 2 hour workshop that offers you a basic introduction to the three different types of composting systems covered in this blog.  After attending the workshop, you will be entitled to a $40 discount voucher which you can use towards the purchase of any of the three composting systems covered in the course.   The workshops take place in a variety of locations and are held regularly.  For more information, visit the following webpage: https://compostcollective.org.nz/