Other bokashis: farm bocashi, EM mulch, fermented grass, and pond balls

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You may have come across the word "bokashi" on a bag of mulch, on clay balls for ponds, or in an article about a fermented fertilizer from Latin America. At first glance, none of this has anything to do with the bucket in your kitchen. Yet it's the same word, and the same starting idea: fermenting organic matter before returning it to the soil or the water.

This overview will help you sort it all out: what each "bokashi" is, how it's made, and what you can reasonably expect from it. Mulch and pond balls each have their own detailed guide in our section on effective microorganisms.

One word for several products

In the garden, the word bokashi can refer to:

• the method of fermentation itself;
• the activator, the fermented bran you sprinkle over the scraps in the bucket;
• the end product, whether fermented food scraps, manure, grass, or yard waste;
• ready-to-use products: mulches, fermented fertilizers, pond balls.

What they have in common: organic matter, often bran, manure, or plant material, inoculated with fermentation microorganisms. Yet the differences between them are considerable. Some ferment without air and without heating up, like the kitchen bucket; others rise in temperature like a compost pile.

Latin American "bocashi": a fertilizer that heats up

In Central and South America, bocashi, spelled with a c, is a solid fertilizer made on the farm. It typically combines poultry manure, soil, bran or rice flour, crushed charcoal, rice hulls, molasses, and yeast or microorganisms gathered in the forest. The pile is moistened just enough: a squeezed handful should hold together without dripping.

What happens next is nothing like an airtight bucket. The pile heats up to 113–149 °F (45–65 °C) depending on the recipe, and it's turned regularly, sometimes twice a day, to keep it from overheating. It's ready in about two weeks, often followed by a curing period before spreading. So it's a cousin of hot composting far more than of kitchen bokashi.

This bocashi is by far the most studied: a review of the scientific literature identified 161 publications between 1999 and 2022, mainly from Brazil, Indonesia, and Mexico. Keep this in mind when you read that "a study has shown that bokashi…": it's often this farm fertilizer, not your bucket. If poorly cured, it can even harm crops: in one trial, three manure-based bokashis were neither stable nor mature, and all of them markedly slowed germination. To find out what studies say about kitchen bokashi, see Bokashi and EM: what the science really says.

Farm bokashi under a tarp

In Europe, farm bokashi follows the logic of the kitchen bucket instead, on a large scale: manure, grass, leaves, crop residues, or yard waste are fermented without air. The method put forward by Agriton, the maker of Microferm, calls for about half a gallon (2 liters) of Microferm, 26 lb (12 kg) of shell lime, and 26 lb (12 kg) of clay minerals per 2,200 lb (1 metric ton) of material. Everything is mixed, packed down, then covered with an airtight tarp for at least eight weeks before spreading. At these volumes, you can also make your own solution: EM-1 activated in a heated tank such as our EM Activator, following the method in our guide Activating EM-1: making your own EM-A.

Shell lime, which is coarse and slow-acting, helps temper acidity, especially with sugar-rich materials such as grass. The manufacturer advises against fine lime, however, as it's considered too harsh on the microorganisms. It was on this type of pile that the lowest losses of organic matter and nitrogen were measured compared with conventional compost.

Fermenting your grass clippings

In the yard, the same method lets you make good use of the grass clippings you collect. The principle, as described by the manufacturer: spray diluted EM onto the grass while mowing or right afterward, mix well, gather into a pile, pack it down firmly, then cover with a tarp. After about six weeks without air, the fermented grass can be used as a soil amendment, mixed into the soil or buried like kitchen bokashi.

Two precautions. Avoid soggy grass, which tends to rot instead of fermenting. And don't use clippings from a lawn treated with weed killer: some residues survive even composting. Doses and step-by-step instructions are in our guide Speeding up your compost with EM (and using grass clippings).

Emy's tip

Pack down the grass pile by stomping on it layer by layer, then weigh down the edges of the tarp with rocks or soil so no air can sneak in.

Bokashi mulch for soil and lawns

Bokashi mulch is a ready-to-use commercial product: organic matter fermented with EM, designed to be spread on the soil. Don't confuse it with the contents of your kitchen bucket. Being acidic and moist, those are never spread on the surface: they're buried, mixed with soil, as explained in our guide Burying your bokashi in the garden.

Our EM Bokashi Mulch for soil can be used in the vegetable garden, around flower beds, or to prepare a lawn, spread and then lightly worked into the soil. Before sowing grass seed, the manufacturer recommends applying it about two weeks ahead of time. Amounts, timing, and what you can expect are detailed in the guide Using EM in the vegetable garden; please also refer to the product label.

Did you know?

Grass clipping bokashi works on exactly the same principle as the silage farmers prepare for winter: packed-down grass, cut off from air, that keeps thanks to lactic acid bacteria.

Pond balls

According to the manufacturer, EM pond balls are made of clay or bentonite, bokashi bran, molasses, Microferm, and ceramic powder. Dried and then placed at the bottom of a private pond, they slowly break down in the muck. The manufacturer credits them with helping to break down sludge and reduce odors.

Independent evaluations are rare and point in opposite directions. In a stormwater retention pond, ammonium dropped by around 65% after the balls were added, but over a short period and with only one ball density tested. On the other hand, a two-year trial, presented in 2025 but not yet published in a journal, saw no improvement in the field; in tanks, the balls made the water worse, with far more phosphates, less oxygen, and a possible input of bacteria indicating fecal contamination. Our position: sensible use in a private pond, alongside good management of leaves and nutrients, and never in a river, lake, or public pond. Everything is explained in the guide Bokashi balls for ponds; our EM Bokashi pond balls come with instructions for use.

What you can expect

All these bokashis share one advantage: they turn organic materials into a stable product that can be stored without rotting and loses little matter until it's used. The benefits for the soil come above all from this organic matter, and trials have not shown any specific effect from the added microorganisms. So choose the right bokashi for the right use, follow the doses on the label, and keep your expectations realistic.

Key takeaways

Same family, different uses: the contents of the kitchen bucket and fermented grass clippings get mixed into the soil, commercial mulch is the only one designed to be spread, and pond balls are strictly for private ponds.

In summary

The word bokashi covers several fermented products. Latin American bocashi is a fertilizer that heats up and gets turned, closer to hot compost; European farm bokashi ferments under a tarp for at least eight weeks; grass clippings can be fermented the same way in about six weeks. Bokashi mulch is a ready-to-spread soil amendment, not to be confused with the contents of the kitchen bucket, which always get buried. As for pond balls, the few independent evaluations are contradictory: they're for private ponds only, never streams or rivers. In every case, the benefit comes mainly from the fermented organic matter, to be used according to the label and without overblown promises.

Related products

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EM Bokashi pond ball | 4 pieces

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Bokashi EM Mulch for Soil | 25 kg bag

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$27.30 €24.45

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Bokashi EM compost activator | 1 kg bag

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Other topics in the guide

Vermicomposting30 fact sheets →Composting25 fact sheets →EM microorganisms26 fact sheets →