An Introduction to Bokashi
What is Bokashi?
Bokashi is a method to deal with food waste that does not rely on the traditional aerobic composting techniques: collecting food scraps then putting them in a pile, allowing the pile to heat up, and then turning the pile to produce compost.
When using the aerobic composting method, often times you may have issues with odors, flies and vermin being attracted to the pile, and the potential for the pile to not heat up since there is not a large enough volume of food scraps at one time to generate the heat required for composting.
Instead, bokashi composting relies on introducing specific types of bacteria and yeasts to the food scraps by sprinkling on a “bokashi bran”. Since this bran contains the bacteria and yeasts but in a suspended, dried form, when the bran touches the scraps the critters spring back into action and begin to break down the scraps.
After adding the bokashi bran, instead of the food scraps turning rancid, they are naturally preserved by the microorganisms just as a fermented pickle or cabbage is preserved in sauerkraut.
This method avoids the food scraps turning putrid and can speed up the the time required to produce usable soil amendments from months to weeks.
Since the food scraps are preserved by the microorganisms, more foods such as bones, fat, dairy, etc. may be added to the bokashi bucket.
Bokashi is a Japanese term and loosely translated means “fading away”, which describes how the treated food scraps fade away in the soil.
How are the microorganisms introduced to make Bokashi?
What can you compost with Bokashi?
In addition to the normal vegetable food scraps, the bokashi process allows you to compost more things than old fashioned aerobic composting.
Items such as:
Meat
Oils and fats
Dairy (milk, yogurt, cheese)
Eggs and egg shells
Shredded Paper
The process pickles these items and stabilizes them so they don’t putrefy. The pickling process also makes these foods acidic and less attractive to wildlife.
What does the whole Bokashi process look like?
The whole process is as follows and can be remembered as 2-2-2:
2 weeks to fill the bokashi bucket and pack it in.
2 weeks to ferment the food scraps in the bucket, and
2 weeks to compost in the soil.
After this the area is ready for plants to be planted.
Where do I store my bokashi bucket to ferment?
Bokashi buckets should be stored out of direct sunlight in a cool area like a garage or basement to ferment.
The microbe families that inhabit the bokashi bran are Lactobacilli (same as in sauerkraut) and Saccharomyces (brewer’s yeast) so a cool area is a great place for these microbes to thrive.
How does Bokashi compare with “old fashioned” aerobic composting?
There are a number of benefits to Bokashi as a composting method:
Bokashi allows effectively composting a smaller amount of material. A proper aerobic compost pile should measure at least 3 feet by 3 feet by 3 feet, however, the bokashi composting process can be any size you want. You’re limited by the container size.
Bokashi provides a faster way to amending soil. Instead of waiting months for aerobic compost to finish and be added to soils, the Bokashi process give you a soil amendment in a matter of weeks.
Going along with the above point, a bokashi system can take up less space. Instead of having to stockpile compost, using the bokashi method allows you to have less in-process compost and thus use less space.
Less effort. Bokashi composting does not require turning, moistening, monitoring. All that needs to be done is to seal a bucket and wait.
Bokashi produces less greenhouse gasses. If you are familiar with regular aerobic composting, the pile will shrink as you compost. This is due in part to the loss of carbon in the compost to carbon dioxide and methane. If the compost goes anerobic (meaning no oxygen is present), then you are also possibly releasing ammonia as well. When less of your compost is turning to gasses, more will be available for your garden!
There are a number of negatives as well:
Bokashi composting requires a airtight vessel and a place to keep it.
Bokashi composting requires an inoculant bran to introduce microbes to the system.
What is the cheapest way to start Bokashi Composting?
There are only 2 things you need to start Bokashi Composting:
Bokashi bran: dried wheat bran treated with microbes
An airtight container
What is Bokashi Bran?
Bokashi bran is a dried, microbe innoculated, grain bran that is sprinkled on food scraps or other material with some water content, which “wakes up” the microbes and allows them to begin digesting the food scraps.
Bokashi bran can be purchased here at Regenerative Soil Amendments or on Amazon.
I prefer Bokashi brans right from the companies that make the microbes. This reason is the microbes are what drive the process, and it’s important that the microbes are known, fresh, and ready to come back to life to start chomping away on your scraps.
Here are two bran manufacturers who also manufacture the microbial inoculant:
Terraganix Bokashi Bran
SCD Probiotics Bokashi Bran
Regenerative Soil Amendments Bokashi Bran
The difference in our Bokashi bran from the two above is in addition to the bran and microbes, we add in biochar, which further helps to capture any odors and nutrients and worm castings, which add even more diverse microbes to the mix.
Our bran is specially formulated for addition to the soil, as it also incorporates trace amounts of volcanic minerals and sea salt to raise the nutrient profile and provide trace elements your soil may be missing.
Beginner Bokashi composting: Airtight containers
In addition to one the 3 brans listed above, you will also need an airtight container to add your bokashi to as it ferments.
It’s important to keep air out of your container as the oxygen will encourage critters other than what’s in your bokashi bran to start growing and you will end up with a moldy mess rather than nicely fermented table scraps.
The cheapest example of these containers is free food grade containers which you can often find at a local bakery or deli.
These buckets are food grade and heavy duty, and the lids come with a seal that will keep the air out of the container as you add food items and bokashi bran. I can buy these containers at my local bakery for $1.50 in a 3.5 gallon size, or if I ask for many at a time, they will often give them to me for free!
The next step up price-wise is to buy a food grade bucket and lid from Home Depot or Lowes.
If you want to go all-out you can buy a food grade bucket and what is called a “Gamma Seal Lid” from Amazon.
Are there purpose-built containers for bokashi composting?
There are purpose-built buckets for bokashi composting, which is a step up over the cheap or free buckets you’ll find at your local bakery.
The buckets come with a spigot and a coarse filter on the bottom, the idea being any liquid can drain away from the bokashi and you can capture the liquid, dilute it, and use it to water your houseplants.
An alternative method to capture this liquid when you’re using a bucket without a spigot is to put some shredded newspaper or cardboard in the bottom of the bucket to soak up any extra liquid.
If you’re just starting out with Bokashi, I don’t think these buckets are necessary as they are a bit pricy - around $60.
Are there any other useful tools for Bokashi Composting?
Since bokashi composting is an anerobic process, it’s a good idea to have something like a potato masher or some other tool to pack the bucket as tight as possible. This will keep any pockets of air (and oxygen) to a minimum as well as allow you to pack more table scraps into a bucket.
Another tool that would come in handy is a long handled spoon or other device to help distribute your bokashi bran in the added layer of table scraps as well as scoop the bucket out into the garden once the composting is finished.
How many buckets and lids will I need for Bokashi Composting?
If you remember the 2’s: 2 weeks to fill the bucket, 2 weeks to ferment the bucket, and 2 weeks in the garden, you should have enough volume in buckets to contain all of your food scraps for 4 weeks total.
You’ll also need at least 2 buckets so you can one sit and ferment, undisturbed, while you fill your other bucket.
For households with 3-4 people, I’d start with 2, 3.5 gallon cheap-or-free food buckets and see how you are able to fill those in 2 weeks. If you need more buckets, after a couple weeks you can pick up a few more buckets.
What is in bokashi bran?
Bokashi bran consists of 3 main ingredients and then often a “Secret Sauce”.
Microbes that can operate in an oxygen free (anerobic) environment. Most microbes that are used are lactic acid bacteria (Lactobacilli) and a brewer’s yeast (Saccharomyces). Both of these microbes are safe to work with, in fact, we eat foods with Lactobacilli, such as sauerkraut and fermented pickles, and drink beverages with brewer’s yeast (beer, wine).
Food for the microbes. This is often something like molasses or some other high sugar source. This will help the microbes to multiply when the bran is being fermented during production, and after the bran is applied to table scraps, it will give a quick boost for the microbes to begin to break down the scraps.
A carbon-rich substrate like a grain bran or paper. This gives the microbes a place to live and a substrate to hold on to the molasses. After the initial fermentation, the substrate, microbes, and microbe food is all dried out to put it in “suspended animation” so it can be stored and shipped and used as needed.
(Sometimes) a “Secret Sauce”. This often includes something which includes different families of microbes (composts, worm castings, etc.), additional substrates such as biochar, or additional minerals and nutrients to feed the microbes and, in the end, the soil.
How much bokashi bran should I use?
This question is a little difficult to answer and has as many answers as table scraps you can compost! A rough estimate would be about 1/2 - 1 gallon of bokashi bran by volume to 3-5 gallons of table scraps.
The main thing you want to do is to try to use less bokashi bran is to distribute the bokashi bran throughout your table scraps, even going so far as to stir the bran into the top layer as you add them. That gives the microbes a quicker path to all parts of your bokashi compost as quick as the microbes can move in the liquid coating the scraps.
Items such as vegetables and fruit scrap will use the least amount of bokashi bran.
Items such as meat, eggs, or fats will use more bokashi bran especially to enable these to quickly acidify to avoid purification and bad smells.
Another rule of thumb is to monitor your bokashi bucket as you add scraps and see how things are going. If the scraps are starting to smell or becoming moldy, add more bokashi bran.
How to make homemade bokashi bran
Can you make your own bokashi bran at home? Sure! Making bokashi bran at home is as easy as baking a cake from a box you buy at the grocery store!
Making bokashi bran at home is as easy as the following steps:
Gather your bokashi bran ingredients.
Gather mixing and fermenting containers.
Measure and mix the dry ingredients.
Measure and mix the microbial blend.
Mix the wet into the dry and add water to the right consistency.
Pack into your fermenting containers.
Ferment your bran and wait.
Dry your bran and store.
That sounds like a lot of steps, but once you have done this a few times, it should only take you about 30 minutes to make enough bokashi bran to last you 1 - 2 months!
What are the benefits of making your own bokashi bran?
The main benefit of making your own bokashi bran is that you know it is fresh and hasn’t been exposed to temperatures that could kill the bokashi microbes.
Bokashi microbes are sensitive to higher temperatures, as they may be exposed to in the back of a hot delivery truck, plane, train, or warehouse. By making your own bokashi bran, you can ensure your microbes are not exposed to these temperatures.
The other benefit to making your own bokashi bran at home is that you can add in your own “secret sauce” ingredients that can provide additional benefits such as additional microbes (via worm castings), additional nutrient holding capacity (via biochar), or other specialty nutrients or minerals to benefit your garden.
How much bokashi bran should I make at home?
At the start, make enough bokashi bran to last you 1-2 months.
As a rough rule of thumb, make enough bokashi bran to equal one quarter the amount of bokashi compost you produce every 1-2 months.
For instance, if you are making four 3.5 gallon buckets of bokashi compost every 1-2 months, start off by making one 3.5 gallon batch of bokashi bran at a time.
This should allow you to keep up with your bokashi compost production to gauge how much bran you need to make in the future as you dial in your system.
A warning about water!
If you are on city water, the water most likely contains chlorine or some other biocide to kill bacteria and microbes.
If this is your situation, pour your water 24-48 hours before you mix the microbial blend and let it sit out with an open lid to allow the chlorine to dissipate.
Otherwise when you mix your microbial blend, the chlorine in the water will kill all your microorganisms!
Homemade bokashi bran step 1: Gather your bokashi bran ingredients
Bokashi bran takes a few necessary ingredients:
Bran - wheat or rice.
Microbes in the form of a purchased microbe mix.
Molasses to feed the microbes.
You should plan to make enough bokashi bran to fill your fermentation container with no air space left over. Since bran can be packed down well, plan on using 50% more bran than your fermentation vessel can hold. Bran can be purchased online or, to avoid shipping costs, at a local farm supply store.
The typical commercial microbes used for Bokashi bran are either Terraganix EM-1 or SCD Probiotics microbes. You’ll need 1-2 fluid ounces of microbes per gallon of bran.
Molasses is used to feed the microbes. Blackstrap molasses can be found at either the grocery store or online. You’ll need a 1:1 ratio of molasses to microbes, so again 1-2 fluid ounces of molasses per gallon of bran.
Other special ingredients can be optionally added, either in bulk or just as a supplement to benefit the composting process and your soil after you introduce your bokashi compost to the garden.
Bulk ingredients that can be used include biochar, shredded paper, or shredded cardboard. When adding other bulk ingredients, you will need to adjust the amount of bran you need to create enough mix to pack into your fermentation vessels.
Supplemental materials to add to your bokashi mix include worm castings, minerals and nutrients such as sea salt, mineral blends, or other sources of nutrients such as kelp meal.
Homemade bokashi bran step 2: Gather mixing and fermenting containers.
When making your homemade bokashi bran, get a mixing container that is 2-3 times larger than the bucket you’ll be keeping the bran in. This will allow you to blend the ingredients without spilling bran. A large Rubbermade storage bin from Home Depot or Lowes can fill this need.
A food grade bucket with a sealing lid (either with a rubber seal or a gamma seal lid) can be used to ferment your bran. It’s important that the lid be airtight to ensure the microbes we’ve selected can grow properly.
Homemade bokashi bran step 3: Measure and mix the dry ingredients.
I use the fermentation bucket to measure my dry materials.
Fill the fermentation bucket with bran or other bulk ingredients and dump it into the mixing tub, and then fill the fermentation bucket again one third to one half full and dump that into the mixing tub as well.
Next add your other nutrients, minerals, or additives to your liking, and mix up everything well by hand.
It’s also a good idea to write down your recipe so you can quickly replicate it in the future.
Homemade bokashi bran step 4: Measure and mix the microbial blend.
Before you mix your microbial blend, make sure you have water that has sat out to allow any chlorine or other biocides in the water to dissipate!
If you do have water from a well, make sure the water is cool to lukewarm to the touch to make sure you don’t kill the microorganisms by excessive heat.
Then it’s as easy as mixing up the microbe blend and molasses in a 1:1 ratio, in about a gallon of water. This will give you a good starting point for up to 3 or so gallons of bokashi bran.
Homemade bokashi bran step 5: Mix the wet into the dry and add water to the right consistency.
Pour the microbe mix into your dry ingredients and start mixing them up by hand.
At first, the mix will be very dry and you’ll have to add more water to get it to the right moisture content.
Add more water slowly and mix well, until you can take a handful of bran and barely squeeze out a few drops of water.
If your bran mix gets too wet, you can add some more dry bran to compensate.
Homemade bokashi bran step 6: Pack into your fermenting containers.
After your mix is the right moisture level, you can pack it tightly into your fermenting containers.
Fill the fermentation bucket about one quarter full of bokashi bran, and pack the bran down.
Add another layer and pack it down, and continue until the entire bucket is filled with bran tightly.
This allows for much tighter packing throughout the entire bucket and prevents air pockets from forming.
Homemade bokashi bran step 7: Ferment your bran and wait.
Once the homemade bokashi bran is packed into the bucket, all you need to do is seal the lid and wait for 2-3 weeks.
This time allows the microbes to multiply by eating the molasses and spread out all over the bran and other ingredients.
Fermentation should take place in a comfortable place for people: 68-80 degrees and out of direct sunlight.
For the first few days, check that the lid has not popped open, and if it has, push it back on. This has happened to me a few times as the fermentation gets underway.
Homemade bokashi bran step 8: Dry your bran and store.
After the bokashi has finished fermenting, find a dry place where you can spread the bran out in a 1 inch thick layer for a week or so to dry out.
A fan can help the bran to dry out quickly as well.
Once the bran is dry, you can put it in plastic bags or other airtight containers until you are ready to use it.
Is it cheaper to make your own bokashi bran?
Yes it is cheaper to make your own bokashi bran over the long term.
A commercially produced bokashi bran costs about $15.00 per gallon of bran.
A simple bran you produce with bulk ingredients will cost about $2.50 per gallon of bran: about $0.80 for the bran, $1.40 in microbes, and $0.30 in molasses, for a total of about $2.50 per gallon of bran.
Of course, there are other considerations such as time and convenience, but especially as you start to produce more and more bran it is definitely worth considering making your own bran!