Bokashi bins are the latest, cost-savvy must-have for turning your kitchen waste into nutritious fertiliser
WHAT IS A BOKASHI BIN?
A bokashi bin is an airtight container where all your compostable kitchen waste is treated with a bokashi bran that contains effective microorganisms (EM) which ferment the waste instead of letting it rot, without producing any unpleasant odours.
HOW DOES IT WORK?
The effective microorganisms in the bokashi bran are good bacteria and fungi like those found in yeast, dairy products and good forest soil. They pickle the contents of your bokashi bin during the fermentation process rather than letting it decay.
The liquid produced during this process can be tapped off and used as a liquid fertiliser. The pickled matter can be added in layers to your compost heap, a lasagna bed or buried underground in existing beds.
Here it will slowly release nutrients and continually inoculate the soil by releasing beneficial substances like organic acids, enzymes, antioxidants, probiotic bacteria and fungi and in doing so continuously improve the quality of your soil and the health of your plants.
WHAT ARE THE PROS AND CONS OF USING A BOKASHI BIN?
- It’s a clean, convenient way to dispose of waste, including things like meat and fish, that aren’t normally added to compost heaps.
- The bins are sealed and don’t attract flies and other pests so they can be safely kept in the kitchen.
- It reduces your carbon footprint as it eliminates the need for refuse collection and transport to a dump, reducing the pressure on landfill sites.
- As the waste is pickled, the only odour is a clean slightly vinegary smell; it’s virtually odour free.
- The bokashi process results in pickled matter that’s virtually odourless
- Bokashi bins don’t need regular ‘feeding’ which the worms in a worm farm do.
- Although you’ll have quicker results if you chop the kitchen waste into small pieces, this is not necessary.
- The pickled contents require further treatment to become a clean, nutrient-rich compost or soil conditioner and need to be buried or put in a lasagna bed (see box overleaf).
- It’s recommended that you use a second bin while the waste in the first one is maturing.
WHAT KITCHEN WASTE CAN I ADD TO MY BOKASHI BIN?
All organic compostable kitchen food waste including cooked and uncooked meats and fish, fresh fruit and vegetables, prepared foods, eggs, dairy products, bread, coffee grounds, teabags, cooked and raw food like seafood, bones and pasta.
Liquids are not suitable.
Some users caution against adding food which is off or mouldy, but small quantities won’t do much harm.
Don’t use animal faeces if the resulting compost is to be used for vegetables as it can contain pathogens harmful to humans.
WHAT DO I NEED TO GET STARTED?
- Buy a bin
Bokashi buckets or bins can be found at many garden centres and hardware stores and range in price from R155 – R300. They also supply bokashi bran which can cost between R40 and R80 for 1kg.
- Make your own bin
An option for DIY enthusiasts is to fix a tap onto a large bucket with a tight-fitting lid. Containers need to have a good seal, a strainer at the bottom and a tap to draw off liquid. To make your own strainer, trim down a lid which has been perforated. You’ll still need to buy the bokashi bran.
HOW DO I USE MY BOKASHI BIN?
- Set up your closed bin or bucket in a convenient, cool position out of direct sunlight. Make sure the sieve or filter is in place.
- Each time you add your kitchen waste sprinkle over a handful of bokashi bran. Press it down firmly to remove any air and replace the lid.
- After a few weeks, start drawing off the tea every 2-3 days and use it as soon as you can.
- When your bin is full, set it aside for a week or two until the top layer of waste is ready. It can then be dug into the soil, added to the compost heap or incorporated into a lasagna bed.
- In the meantime, you can start on your second bin.
HOW DO I KNOW WHEN THE PICKLED MATTER IN MY BOKASHI BIN IS READY TO BE USED?
When the contents of your bokashi bin are covered with a flat, white fungus.
HOW DO I TURN THIS PICKLED MATTER INTO NUTRITIOUS COMPOST?
At this stage, you have four options:
- If you have a large garden, dig a hole about 30cm deep and bury it in thin layers. It will break down and the nutrients will move into the surrounding soil. Repeat this with successive batches of pickled matter in new places.
- In small gardens, simply sink a 30-litre bottomless bucket into the ground. As you add the pickled matter, cover each layer with a little soil. It’s best to keep the lid on your bucket.
- Add it in thin layers to holes in the centre of your existing compost heap.
- Use it in a lasagna bed. (CLICK HERE FOR INSTRUCTIONS ON MAKING A LASAGNA BED)
HOW TO USE BOKASHI TEA:
- To feed the garden and pot plants as a soil drench, dilute it 1:100 with water.
- It’s best not to use bokashi tea as a foliar spray as it’s acidic and can burn the leaves.
- Use the undiluted tea to clean drains, the pipes in your sink and shower; it will digest deposits in the pipes. It can also improve the efficiency of your septic tank.