Bokashi Composting

What is bokashi?

Bokashi is a fermentation method for kitchen waste. Scraps go into a sealed bucket in layers with an inoculated bran, and over about a fortnight lactic acid bacteria and yeasts pickle rather than rot them. The result is buried in soil, where it breaks down quickly and feeds soil life.

Turn kitchen waste into living soil food

Bokashi is a Japanese fermentation method that turns kitchen and garden waste into a dense soil food in ten to fourteen days, using EM (Effective Microorganisms), a blend of beneficial bacteria, yeasts and photosynthetic organisms developed by Dr Teruo Higa. Rather than rotting scraps in a heap, you ferment them in a sealed bucket. The result is a nutrient-dense pre-compost that keeps far more of the vitamins, enzymes and microbes that hot composting cooks off. If you are new to it, start with what bokashi bran is and how to use it.

Why bokashi beats a compost heap

• Everything goes in. Meat, dairy, citrus, cooked food, onions. Things a heap cannot handle.
• Two weeks, not two seasons. Fermentation finishes in a fortnight, then a short soil burial unlocks it.
• No smell. Sealed anaerobic fermentation smells faintly pickled, not rotten.
• Higher nutrient retention. The process runs cool, so nothing is cooked off.
• It inoculates as it feeds. Every application puts billions of beneficial organisms straight into the soil food web.
• No turning. The bucket does the work.

Effective microorganisms, EM-1 and what the bran is

Effective microorganisms is a defined mixed culture rather than a single species: lactic acid bacteria, yeasts and photosynthetic bacteria held together in an acidic, stable liquid. EM-1 is the mother culture that everything else descends from. Bokashi bran is simply a carrier — wheat bran that has been inoculated with that culture and dried, so it can be sprinkled dry over each layer of waste and can sit on a shelf until you need it.

Worth being straight about the evidence. The fermentation itself is not in doubt: seal food waste with a lactic culture, exclude air, and it acidifies rather than putrefies, which is the same chemistry that makes sauerkraut. What is harder to pin down is how much of the applied microbial population persists once the material goes into a garden soil that already has its own biology, and published trials on EM in field soils are mixed. The reliable benefits are the ones you can see: waste diverted from the bin, organic matter returned to the soil, and a fast, cool process that keeps nutrients in the material rather than losing them as heat and gas.

What is in this collection

• Bokashi Bran. EM-inoculated wheat bran in fully compostable packaging. Sprinkle over each layer of waste as the bin fills.
• EM-1. The original Dr Higa mother culture, for activating your own bran or making your own ferments.
• Unsulphured sugar cane molasses. The carbon food source the microbes need to multiply. Essential if you are activating EM-1 yourself.
• Grow-Kashi. A ready-to-use fermented top-dress for established beds and pots, if you want the benefit without running a bucket.

Kitchen waste composting, from the worktop to the bed

Bokashi composting is a two-stage workflow, and most of the confusion around it comes from people expecting one stage to do both jobs. Stage one happens in the kitchen: waste goes into the bucket as it is generated, gets pressed down to drive out air, takes a scattering of bran over each layer, and the lid goes back on. Nothing is turned and nothing is watered. When the bucket is full it stands sealed for ten to fourteen days while it ferments.

Stage two happens in the garden. The fermented material is buried in a trench, in a spare corner, in a deep container, or added to an existing heap. Soil organisms take it apart quickly because the fermentation has already done the hard structural work, and within a few weeks it is indistinguishable from the soil around it. A bokashi bin makes stage one tidier, with a tap for draining the liquid and a plate for pressing, but any airtight bucket that seals properly will ferment just as well.

What to do with the finished ferment

Bokashi pre-compost is not compost yet, and it is acidic when fresh. Bury it in a trench or add it to a heap, wait two to four weeks, and then plant. Worked into a soil mix or used as a top dressing it adds organic matter and feeds soil biology directly, though it supplies far less concentrated nutrition than an organic fertiliser, and there is more to it than the kitchen bin suggests: how to use bokashi bran in your soil.

If you want to take the biology side further, the microbial inoculants collection covers mycorrhizal fungi and microbial concentrates.

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