Bokashi Composting is possibly totally new to you. Perhaps you’ve heard it mentioned and wonder whether it is a way for you to compost when you live in a flat. Or perhaps your family ends up with lots of cooked food waste and you’re wondering whether Bokashi would be a cheaper way of dealing with it than getting a dog…
Read on for explanations, tips, pros and cons.
Read on for explanations, tips, pros and cons (plus links to other helpful blogs at the end).
Bokashi is a Japanese word meaning “fermented organic matter.” Developed in the early 1980s by Dr. Teuro Higa, Bokashi was originally a Japanese system of composting in a closed environment where oxygen is excluded.
This makes it totally different from other forms of composting. It is anaerobic fermentation which produces both the liquid and the fermented material, or ‘compost mush’ as my children used to call it. And indeed although it’s called a compost method (which it is) the process feels more like pickling than composting! Which means that those of you who preserve surplus home grown veg by pickling should get your heads around this system fairly quickly.
How Does it work?
Effective Micro-organisms or EMs, are what make the Bokashi system work. These beneficial micro-organisms survive without oxygen, and are naturally found in soil.
The Bokashi system can work well in flats and offices where there may be limited outside space for a traditional compost bin. Two air tight bins or buckets are necessary – one in use, one ‘cooking’ or ‘resting’. Because they are air tight they can be kept inside or outside.
The system involves layering food waste, including meat and dairy products, with an inoculant – usually wheat bran and molasses. This is the food for those EMs.
The Bokashi Composting Process
Although both buckets can be kept outside, it’s far more convenient to have the one in use near to hand in the kitchen or utility room.
You do need to isolate the materials from oxygen as much as possible. The bucket should be opened only to add scraps, not to check on the materials. When I use a Bokashi system I press the food waste into the bucket to squeeze out any air. A layer of thick cardboard on the top of the mix enables easier squishing and helps with the air exclusion.
As with wormeries, a nutrition rich liquid, or leachate, is produced and this should be drained off regularly during the fermentation process. The buckets are provided with a tap at the base for this purpose. The leachate can be diluted to use as a liquid fertiliser for your houseplants and garden plants, both edible and ornamental.
When the bin is full it’s left for two weeks to finish the pickling process. NB you will still need to drain off any leachate during this time.
Bokashi Composting Problems
Mould
Basically, white mould is good, but green mould and or black mould are bad
If you see white mould, be happy. This is part of the natural process. Green or black mould is not good: it means something has gone wrong. You’ll have to throw this mix into the council food waste (preferably) or the rubbish bin and start again. The cause of the mould is most likely to be that too much oxygen got into the bokashi bin.
Tap leaking
Don’t you hate it when this happens? If there’s just an occasional drip, the easiest solution is to put a small pot underneath to catch the drips. Remember to empty it regularly to prevent smells. Add it to the leachate you’ve already collected.
More ominous tap leaks, perhaps around where tap sits into the bucket, can usually be resolved by using plumbing tape. A fiddly job winding this round but it should work. Luckily, I’ve not had this problem (yet).
If a combination of tape and bowl don’t resolve your problem then you may need to chuck everything out of the bin so you can have a proper look inside and hopefully resolve the leak issue.
If it’s a recently bought new Bokashi system then obviously get in touch with the firm as it shouldn’t be leaking! The problem is more likely to arise with old bins.
Smell
During the formation process you may get a yeasty / fermenting or pickling smell, depending how your nose defines these things. This is a good thing.
However, a rancid odour is bad, and it will be due to one of two things. Either you (inadvertently) let oxygen get in, which case you’ll probably see green or black mould. Or you forgot to drain off the fluid and its ‘backed up’ into the mush. If it’s the latter, then drain off all the fluid, add some more inoculator bran and check again the next day. If you’re lucky it will have resolved the problem, if not, throw away and start again.
What to do with the Pickled Bokashi
When the bin is full it needs to be left for two weeks. Now, the resultant mush after standing isn’t compost in the normal sense and cannot simply be spread around as mulch. Generally, it’s added to an ordinary compost bin or dug into the ground to finish decomposing aerobically.
There are lots of ways to use the mush and leachate. For example, office staff could take it to their own garden or it could be used in the communal garden if there is one. The nutritious liquid is another, separate, benefit for staff who have gardens or houseplants.
Where you live in a flat and only have a balcony, the liquid will be useful, but the partially decomposed “compost” less so. This could be donated to friends and family with gardens, community gardens (although check first). Or even put in your food waste bin. And no, that isn’t a waste as you’ve made your own liquid fertiliser for your balcony plants and house plants.
What I like about using a Bokashi composting system alongside other, more conventional methods, is –
- being able to turn meat bones, dairy and cooked food scraps into compost at home
- that ability to quickly decompose food even in winter
- the Bokashi ‘compost tea’ – more home grown fertiliser!
- it’s a highly nutritious plant food that can be buried in planting holes to give young trees a great start
- that it can be layered with clean, used, potting compost to add fresh nutrients. Once your layering is done, leave it for a couple of weeks to combine on its own before using. For example, I find its good for repotting plants and some houseplants that could do with a nutrient boost not just fresh soil.
Bokashi Composting Pros and Cons
Pros
-
- Meat scraps, dairy and cooked food can processed at home unlike other forms of composting
- Bokashi composting can be done in a relatively small space
- The end ‘mush’ is a highly nutritious plant food that can be buried in compost trenches
- Alternatively the fermented material can be added to compost bins and wormeries
- The leachate produced makes an excellent liquid plant feed
- You are able to re-purpose all of your food waste (very satisfying on many levels)
Cons
- The mush produced is a fermented product, not a traditional compost and needs to be further processed. For example, added in layers to traditional compost bins or in small amounts for wormeries before it’s fully decomposed.
- Regular purchase of the special inoculant bran
- An airtight bucket or bin with tap to drain off the liquid is needed – either bought or home-made
A pair of old Bokashi buckets I found when having a clear out – still usable!
Is it for You?
Is Bokashi Composting right for you? It certainly has its place in the overall scheme of reducing our impact on the planet, re-using, recycling and economising.
If you garden organically, if you’re vegetarian, piscarian or vegan – it is fine to use the Bokashi method (although you may be omitting meat bones or dairy!)
But perhaps you’re not sure that you’ll really use it and are wary of spending perhaps £100 on getting set up? Why not look for a second-hand kit online or in neighbourhood forums; there’s often one for sale or free. Or if you enjoy DIY you could make your own. A friend may even loan you theirs for a while to try it out.
and finally
You might also find our eBook “Compost and Composting” useful. And if you do have a go with Bokashi Composting, let me know how you get on! Perhaps with a pic?
Whatever you do, enjoy your garden and if Plews can help you with anything, please do get in touch. For example –
Our Garden Consultancy & Advice Visits may help with some of your issues. Or does your planting need a rethink? Do you have a birthday coming up? Plews bespoke Gardening Lessons, where your classroom is actually your own garden make a wonderful and practical gift. You could learn how to grow an orchard of citrus fruits in your conservatory! We help you with both gardening basics and more ‘expert tasks’, depending on what you need. Have a read through this pdf download for info.
For further gardening advice and inspiration, check out Plews Potting Shed blogs, including the selection below. You could come and find us on Instagram Pinterest and Facebook too.
Feeling nosey? You can have a peek at the progress of my garden renovation, Spitfires and Slow Worms, on Instagram and Facebook
You’ll get to see it in person if you come to the Plews Gardening Workshops Current ones on Eventbrite for you to book into. Follow for updates on topics and dates on Plews website, Instagram, Eventbrite, Facebook
Plus get your local garden club, allotment, WI, U3A or other group to ask me along to give a talk (and bring plants 😉)
Related Gardening articles you may enjoy from our Award Winning Blog
What is Organic Gardening?
How to Make Compost
Uses for Weeds – Liquid Fertiliser
What is a Vegan Garden?
7 Uses for Old Coffee Grounds in the Garden
