Bokashi composting, also spelled bocashi composting, is a new way to deal with kitchen scraps. The proponents of the system claim that it has a number of benefits not found in more traditional composting methods. In this blog post, I will have a close look at Bokashi composting and separate myth from reality.
Bokashi Composting—What is it?
From Bokashicomposting.com we have the following description: “Bokashi composting is a safe, convenient, and quick way to compost food waste in your kitchen, garage, or apartment.”
To get started, you need a special bokashi bucket that has a tight lid and a spigot at the bottom to drain off liquids (pictured above). These will run you $60 to $150, or you can make a DIY for $20. You also need the ‘special sauce’! It would not be a very good process if there was no special sauce to sell you. It is normally referred to as bokashi bran or Effective Microbes.
The process is fairly simple. Put your food scraps in the pail and sprinkle some bokashi bran on top. Squish it down tight to get the air out. Close the lid. Each time you have more scraps, add them to the pail, add bran, and squish.
After a few days, liquid starts to form in the bottom of the pail. This needs to be drained, or it will start to stink. This liquid, the ‘bokashi tea,’ can be used to fertilize your house plants or your garden plants.
After a few weeks, when the pail is full, you take the contents outside and either dig it into your garden or add it to your compost pile.
That is the basic process. If you want more details or have specific questions about the process, there is lots of info on the net.
Benefits of Bokashi Composting
I found the following benefits listed at various sites on the net.
1) You can compost dairy products and meat.
2) No strong odors
3) No nutrients lost
4) No insects or rodents
5) No turning necessary
6) No need to worry about the amount of greens and browns
7) Food scraps are inoculated with EM (Effective Microbes)
8) Produces a nutrient-rich tea for plants
9) Can be carried out on a small scale, which is perfect for apartments
10) Very quick—complete in 2 weeks
11) Saying the word ‘bokashi’ will impress friends. 🙂
This sounds like a good system, and any system that returns kitchen scraps to the soil is a good thing. So in general, I have no problem with bokashi composting. If it gets you composting—great.
But… there is always a but. Is this really a method of composting? Is this system better than the more traditional methods of composting? These are the important questions and the ones I will look at in the rest of this post.
Bokashi Composting—Is it Really Composting?
If you read the above quickly, you might have missed the statement that says, “After a few weeks, when the pail is full, you take the contents outside and either dig it into your garden or add it to your compost pile.” Does this make sense? Why would you add fully composted material back to the compost pile?
If you read the fine print, you soon understand that bokashi composting is not a composting process at all. Bokashi in Japanese means to ferment. This process is actually a fermentation process. What you are doing is turning your kitchen scraps into pickled kitchen scraps. At the end of the process, the food looks just like it did when it went into the system, except it’s pickled. An orange looks like an orange, and an apple looks like an apple.
There is no composting taking place in bokashi composting—talk about false advertising!
Knowing this fact makes the earlier statement make more sense. Once you have fermented your scraps, you then need to compost them. You can do this by adding them to a compost pile, or you can just dig them into your garden soil, where they will compost naturally.
This system is especially promoted for apartment owners—what do they do with it after fermentation? Throw it in the garbage? They could have done that before fermenting.
Now that you understand the process, it is also clear why it is so fast—only 2 weeks. It is fast because there is no composting, which is a slow process.
Bokashi composting is not composting!
Bokashi vs Traditional Composting
The benefits listed above as #2 to #6, inclusive, are really not benefits when we compare the two methods. I make compost in bins and don’t worry about greens and browns—I just add whatever I have. It is outside, so the smell does not bother me, and if a mouse comes by for a bite to eat, so what! Nutrients can be lost if it rains too much, but they are lost to the soil below the compost pile—they are not really lost since the tree roots under the compost pile use the nutrients. If I really care about nutrient loss, I can cover the compost pile to keep out the rain.
Traditional composting, if higher temperatures are reached, can even compost meat and cheese.
The difference in the two systems is the pickling process. The apparent benefits of pickling are the Effective Microbes added to soil and the bokashi tea.
For more information on traditional composting, see Compost—What is Compost? and Benefits of Composting.
For a detailed comparison of Bokashi and traditional composting see, Bokashi vs. Composting.
Effective Microbes
Dr. Higa, the person who originally developed the bokashi system, also developed a special sauce that he called ‘Effective Microbes’ (EM). All kinds of special properties have been assigned to this mixture, but nowadays lots of people sell the microbes already added to the bran. Everyone in the industry now has their own ‘secret sauce,’ i.e., Effective Microbes + bran.
Adding the microbes is important since they control the fermentation process. For example, in winemaking, special starter yeast mixtures may be added to start the process. The reason for doing this is that you want the right kind of microbes to grow quickly and outcompete the ones that will create a lot of bad odors.
There are also claims that the EM are good for the garden. There are some studies that show a benefit from the microbes, but most show no positive results.
Testing of EM tea on field-grown crops found that they did not increase yield. Similar field studies have shown the same results. Effective microbes are important to make the bokashi system work, but they don’t really add any benefit to your garden.
Note (added April 2021): More recent research indicates that even the EM microbes may not be required for making Bokashi.
Nutritious Bokashi Tea
As fermentation progresses, excess liquid drains into the bottom of the pail, and you need to remove it. It is claimed that this tea is a great source of nutrients for your plants.
How nutritious is it? Some sites say that you can use it straight or dilute it 1:100. That is a huge red flag. A fertilizer that can be effective at full strength and at a 100 dilution rate does not make sense. Some people have commented that “it’s a biology thing, not a chemistry thing, and so the dilution does not matter.” They are saying ignore the nutrients because it is the microbes that are important. I addressed that in the discussion above. The science does not support the idea that the microbes add value. Even if they did, dilution by a factor of 100 would still be important.
There is very little published about the nutrient levels in Bokashi tea, which is odd since so many websites promote it. I did find one study and analyzed it in another post called Is Bokashi Tea a Good Fertilizer?
In short, it contains very little nitrogen, high levels of P and K, and several of the micronutrients are on the low side. It also contains high levels of sodium and chloride, both of which are toxic to plants at low levels.
Bokashi tea should not be used on container plants, and even in the garden it should be diluted 1:100 before it is used to reduce any potential damage from sodium and chloride.
Real Benefits of Bokashi
I am still not sold on Bokashi. The tea has no real value, and the fermented food scraps still need to be disposed of. If you are going to dispose of them in the garden, you might as well compost instead.
In recent years a new way of handling the Bokashi ferment, called Soil Factory, has become popular. I have discussed it in detail in Soil Factory Using Bokashi Ferment. It is a way to process the scraps in the home in a few weeks. You can even use my improved Instant Soil Factory method and eliminate the two-week period. Using these methods, Bokashi makes sense for apartment owners and others with no garden.
Both bokashi composting and traditional composting provide your garden and plants with the same benefits. Bokashi just seems to be an additional extra step that is not necessary. I would not use it.
That leaves us with one benefit from the list presented above, and this one can’t be denied. Saying the word ‘bokashi’ is cool and will impress your friends.
This article was very imformative, but it best opened up a very good discussion on Bokashi vs traditional composting. Before I give my 2c, I want to thank everyone for participating in a debate without resorting dissing and namecalling, which most of these type of discussions bring. I’m going play off of what Lisa Andrews said with maybe a little twist.
I started heavily studying composting because I’d sworn to keeping Scott’s out of my yard after it was determined that it was build up of Nitrogen salts that killed off a once beautiful lawn and allowed fungus come in a eat the yard away. I committed to go fully organic and to self sustain my fertilizer needs with my own compost. Well, in doing so, I was keeping kitchen scraps and just throwing them on the pile as the little can filled. FOund out that’s not the most effective way to develop good compost. Pulling the parts together and filling a cubic yard of the right things proportionally could produce compost effectively in 30 days.
This is where Bokashi came in. Where do I save up the food scraps while I’m waiting to build up Carbons and Nitrogens to build up a cubic yard of stuff? Bokashi composting seems to me to be the answer to my problem.
1) I have a structured process of keeping weeks of kitchen waste while I build up compost material.
2) Adding meats, cheeses, milk, etc. is now back in the game. I’m throwing away even less kitchen foods now.
So in other words, I see nothing but a win-win situation for supporting both. I look at it as complimentary cycle of the Bokashi composting method feeding the traditional composting as innoculator, where it will aid in the increase of the decomposition process.
So this was my reasoning for both, but I respect the fact that people living in small places or limited space and can’t (or don’t want to) traditionally compost, use the Bokashi method.
Do I still have questions about Bokashi? Yes, but one question I don’t have is if that there is room in my self sustaining organic process for both. Room for both!
The only reason I’m considering Bokashi is the claim of not attracting rodents and flies. I tried sifting through comments on this to see if there is any believable experience validating this. But got lost in a sea of contentious debates unrelated to this. There are many of us living in the space “between an apartment and a farm”, i.e. urban but with a garden. Anything that reduces flies and rodents is a huge benefit to me. I saw one anecdotal claim that pet rats like fermented foods…but that doesn’t tell me if wild rats come after Bokashi. So…any comment on how attractive Bokashi is to wild rats and flies once put out in a compost bin?
1) While you are fermenting, the bokashi should be covered – not rat problem.
2) When you put the bokashi ferment into the garden, some people do report a rat problem.
3) Some say that if you have a rat problem, you did not ferment long enough. Not sure how you can tell when it is long enough.
https://bokashiliving.com/question/big-rats-problem/
In my experience, rodents do like fermented foodscraps just like any other foods. I mix the fermented mass with soil in closed/rodent-secured bins, which reduces the problem. They might still come round to check out places, but since any actual bits of food disappear relatively quickly, so does the appeal for rodents to come.
Hi. Excelent article! I love the way you use science (or the lack of it) to refute myths.
I have no intention of doing bokashi but hope you can help me with some doubts because I teach environmental education (in Chile) and I like to deliver information with a scientific basis:
1.) I understand that, since Bokashi process is anaerobical, it produces methane, right? Doesn´t this fact makes it harmful rather than beneficial?
2.) In the same theme, I have read that the anaerobical microorganisms that works on Bokashi doesn’t produce methane in their metabolism. Is that posible? And if it is, is there any way to select just that kind of microorganisms for bokashi?
3.) What about the production of CO2 and methane on composting and vermicomposting techniques. Is it significative or negligible?
Thank you very much for sharing your knowledge. It has helped me a lot in my classes.
Best regards,
Ibin Silva
This might help. https://www.gardenmyths.com/composting-climate-change/
Thanks. Again, very useful information.
But I still have the doubt about bokashi fermentation. Does it produce methane? I asked it to a bokashi seller (obviously waiting a biased answer) and he said that they select only micororganisms that doesnt produce methane. Is it even possible?!?
The bacteria that grow in acidic anaerobic conditions would not produce much methane. It is probably not zero. The problem is that at the end of bokashi process,the food is not yet decomposed. It now has to go through a normal decopostion process which will produce methane.
Thanks!!
Effective Micro-Organisms (EM) are facultative meaning they can work both aerobically and anaerobically. Microbes also very rarely die. When the conditions do not suit a particular microbe they are suppressed but if conditions change they will repopulate.
Putting Bokashi, and therefore microbes, that are facultative onto your soils you are having a positive impact on your soils with countless peer reviewed papers documenting exactly that. The facultative microbes support and “back up” the microbes already on the waste or in the soil or in the compost helping achieve the desired outcome.
Your understanding of how Bokashi breaks down in the soil is also wrong. As the microbes have been breaking down the organic matter in the bin the waste does not need to be turned into compost to be used in the soil. It is immediately available as a food source to life in the soil.
Composting is nothing more that rotting which loses 50% of the carbon and organic matter to the atmosphere and as the readily available carbohydrates are the first to be lost you are left with little more than lignin.
By using Bokashi you reduce greenhouse gases by over 50%, increase organic matter by over 50%, increase nitrogen by 40% and have 100% more available energy compared to compost.
Composting is better than nothing don’t get me wrong but from an environmental and regenerative and soil fertility view point it is a poor second best in comparison to Bokashi.
1) Re: “microbes, that are facultative onto your soils you are having a positive impact on your soils with countless peer reviewed papers documenting exactly that”
I have spent a lot of time looking for such evidence and have not found it. But since there are countless studies – please post a link to that shows soil microbe populations increase after adding microbes to the soil.
2) Re: “As the microbes have been breaking down the organic matter in the bin the waste does not need to be turned into compost to be used in the soil.”
The way organic matter is “used in the soil” is by it being broken down by microbes. It is my understanding that at the end of the Bokashi process the food scraps are still recognizable – clearly showing that there has not been much decomposition yet.
Dear Sir,
I’m from Mauritius. I wish to buy the Bokashi bucket to compost food waste from the canteen.
Can you please help me where can i get the bucket, please.
Thanking you in anticipation
Check online – I don’t sell them.
When it comes to critters not going after fermented it’s wrong.
Birds, foxes, european badgers and dogs sure like it, and you need to make it impossible for them to get to it or they will go after it and the worms and such that feeds on it.
I can’t say I have personal experience when it comes to rats and ferment.. but atleast according to a couple of rat owners there pets like fermented foods. So I wouldn’t think that wild rats would skip a free lunch just because it’s bookashi.
Tried it not impressed. Did smell, if mostly vinegar. What I found out it toke its sweet time.
I did a couple of test. I took fresh scraps (freezed really) in one part of my worm compost. The same amount and from the same type but instead of freezed fermented with bookashi. Another part I left freezed food stuff in earth and on fermented in earth.
Conclusions was that under the environment I had wormcomposting freezed/fresh was the fastest and that didn’t include the time for fermenting, just for the worms and all the microbes to handle it. Second was the fermented in the wormcompost and last frech in earth.. but it all boiled down too if I should count in the time for fermenting or not.
I think the worm with freezed food did end up with mostly no food left (bones and avocado peel and seed excluded) twoo weeks before the bookshi in wormbin. Excluding the time for ferment. Had I put the food scrap in at the start of fermenting it would have been a month faster.
When it come to meat and shell from shellfish it did compost quite easily in the worm bin either fermented or not, but took it’s time.
Bones (from duck) did stay even after a year. The differens that I could see was that bones that was fermented stayed white
a lot longer than the freezed ones. They become brown faster. But a year after I couldn’t say there where much difference in any important way and I ended the experiment. (Some bones can maybe have been more brittle without the ferment than with.. but it was minuscule and at that time I was really against bookashi so can have impacted this part.)
Would have loved doing an experiment between hotcompost , wormbin and in earth and with both frech scraps and fermented to see the difference. Bot I don’t have a hotcompost.
Ok, I really would like if Robert would bother to use Bokashi & test it out for himself, get the testing done on the results himself, & stop just badgering the supporters of a good initial recovery system for recycling of organic wastes, but it seems after years of this article that he will not be doing that. SO, I will go through his initial list & tell him point blank what are real benefits, & what part of his list are made up to sell a product you can produce with milk & bakers yeast.
“Benefits of Bokashi Composting
I found the following benefits listed at various sites on the net.”
1) You can compost dairy products and meat. – This system does not compost, it ferments allowing for the addition of many organic products. The fermentation softens organic items reducing later composting time & also making wastes easier for worms to help process.
2) No strong odors.- The fermentation process produces acetic acid which smells basically like vinegar. Other odors are reduced though still exist. There are no putrid odors from aerobic rotting processes.
3) No nutrients lost.- This is a complete fallacy. Nitrogen will be lost with the production of methane as part of the fermentation process.
4) No insects or rodents.-This is obvious. You are using a closed system, so no insects or rodents are able to enter.
5) No turning necessary
6) No need to worry about the amount of greens and browns
7) Food scraps are inoculated with EM (Effective Microbes)
8) Produces a nutrient rich tea for plants.-This is debatable though not likely. The runoff is simply liquid ferment, mostly bacteria & fungus from the mixture.
9) Can be carried out on a small scale which is perfect for apartments.-Composting can be done on a small scale as well, so this benefit seems a bit trumped up, but is true. It can be done in a 5-gallon bucket.
10) Very quick – complete in 2 weeks. Technically it is not complete in 2 weeks as the step after fermentation is to bury it in the garden for further process. There, it will continue to compost & will fill with earth worms & red worms consuming the bacteria & fungus grown during the fermenting process.
11) Saying the word ‘bokashi’ will impress friends.-It is a neat word, but your friends must be really easy to impress.
Do you proof of this statement, “The fermentation softens organic items reducing later composting time & also making wastes easier for worms to help process.”?
Do I (assuming you mean have here) proof of this statement? If I am understanding you correctly, the proof is in the putting as the old saying goes. Robert, get a 5 gallon bucket with a lid & do it for yourself. It is embarrassing watching you look for things to pick apart on this. I have performed bokashi on many occasions, & all materials except hard wood products softened considerably.
Proof as in scientific studies. You claimed ““The fermentation softens organic items reducing later composting time & also making wastes easier for worms to help process.”?” Where is the science to support this statement?
Doing something yourself in a bucket without proper controls is just anecdotal information and not proof of anything.
https://www.gardenmyths.com/anecdotal-evidence-not-worth-the-screen-its-displayed-on/
It might not be scientific, but hay the sun comes up in the east and sets in the west. Facts are facts. The b acteria are breaking down and fermenting the waste making it more available during compost. That’s the whole point. If it didn’t work he would have told you. His whole point was to point out the flaws with the original post it’s not like he has an agenda.
No idea who “he” is?
I never said Bokashi does not work. What I said is that it does not compost the material and that there seems to be little evidence that doing bokashi before composting adds any benefit.
Up to 40% of waste going to landfill sites is organic matter (not my stats). As responsible people we all need to be striving to reduce our footprint. A bokashi bin will remove the organic material from the landfill. The recyclables don’t stink anymore either. Bokashi bins should be in evry home!
Agree with reducing the waste, but there is little evidence bokashi is a good option. It still needs to be composted at the end of the process.
We have only just started to compost and to grow fruit and vegetables. We are in Australia and plastic pollution is a big problem. A problem we are trying to take into our own hands as our government isn’t doing enough about it.
All fruit and veg comes in plastic packaging unless you find a farmers market, then you need a plastic bin liner or bag because of food scrubs. Not all plastic can go in the recycling bin either. So, we are trying to reduce our rubbish going into land fill. Food scrubs release a lot of greenhouse gases so we wanted to find a better solution. The Bokashi is great because we can throw almost all food scrubs in it. The way we do it is to first offer it to the dog, if he can’t have it we check if it can go into our compost bin, if that’s a no, we throw it into the Bokashi to be fermented. I have pretty much thrown anything in there, left over cake, cooked pasta, dairy, oil, anything. Once it’s full I leave it to be fermented and start a fresh bin. When that is full I throw the contents of the first bin into the compost bin. We get really dark soil out of it. By following this we were able to reduce our rubbish to 15%. I guess we can do better as we archived this without even trying too hard but it’s a start. I did read that the liquid may be diluted and used as fertiliser. I guess Bokashi has been originated in Japan and many people do it over there with a lot of success. Maybe someone from japan can shed light on weather it’s worth using it as a fertiliser. For now we are happy that we have reduced our waste.