Tout juste 2 heures après l’atterrissage de mon avion à Sapporo au Japon, j’avais déjà les mains dans le fumier de volaille pour fabriquer du Bokashi, un fertilisant traditionnel japonais. Cela m’a donné l’idée de créer un exercice sur la place de la fertilisation comme pratique plus ou moins agroécologique dans le contexte japonais.



L’article est en anglais; la traduction fait partie du travail des étudiants et peut être faite de manières différentes:

  • En divisant l’article en thématiques et la classe en groupes
  • En travaillant sur plusieurs articles en anglais et les étudiants peuvent faire la traduction d’un article pour le reste de la classe (implication des étudiants ++)
  • De manière basique, chaque étudiant traduit de son côté et peut utiliser tous les outils qu’il souhaite (google traduction)


—> A noter que la ferme que l’agriculteur interviewé pour cet article fait partie du réseau des Agron’Hommes et donc accepte des réunions Skypepour répondre aux questions des étudiants dans le cadre du projet des Agron’Hommes. Il accepte aussi des stagiaires, toujours dans le cadre du projet.


Les objectifs de l’exercice sont:

  • de comprendre en quoi l’utilisation du bokashi est une pratique agroécologique
  • d’imaginer s’il est possible de fabriquer du bokashi – et pourquoi le faire – dans un autre pays, avec un contexte différent
  • de tester la fabrication du bokashi à petite ou grande échelle, dans le cadre d’un cours

L’exercice est adaptable aux niveaux :

  • BAC S option agronomie

Notions/concepts abordés:

  • Fertilisation
  • Fermentation
  • Nitrification
  • Rapport C/N

Je propose beaucoup de variantes selon le niveau, les possibilités de l’enseignant et notamment la possibilité de travailler en équipe pluridisciplinaire:

  • Anglais
  • Agronomie
  • Biologie
  • Histoire
  • Géographie
  • Techniques d’information et communication / informatique


En lisant l’exercice vous comprendrez en quoi il implique autant de disciplines et comment faire participer chaque enseignant.

Attention ceci n’est pas un exercice « clé en main » l’enseignant devra probablement faire une préparation avec notamment des recherches personnelles pour disposer d’éléments de réponse précis.


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Bokashi: tradition and agroecology in Japan

In Menno Village farm, I had the opportunity to make and use bokashi, a traditional Japanese fertiliser. From this point, I had the idea to create an exercise about fertilisation and agroecology on a Japanese farm.

Video : https://youtu.be/6_uMufgbyzI

In this video,Raymond Epp, farmer in Menno Village, explains the basics of bokashi making and why it is made on the farm.

Here are some additional sentences from Raymond:

  1. « It ferments 3 weeks. We dont have a very precise recipebut we have to be careful with the amount of water and straw. Too much water will hinder the fermentation process because of a lack of oxygen. At the moment the fertiliser smells too strong… »
  1. « Very few Japanese farmers use bokashi nowadays»
  1. « Normal compost would have more carbon. Chicken manure contains on average 2-3% nitrogen and the same amount of phosphorus. It is the same for rice bran. Tofu waste probably has higher nitrogen.»
  1. « When you fermentrice bran and chicken manure together you lower the fermentation temperature and so denitrification is reduced as well »
  1. « If it smells wrong it means that there is something wrong on the farm. In a forest it is composting slowlyYou can enjoy having a picnicthere because it doesnt smell. When we make bokashi, if it smells too strong it means I am doing something wrong. Nobody wants to have picnic in a stinky place»
  1. « When we had trainees on the farm we were making 120 bags of Bokashi. Today we make 40»
  1. « We dont fertilise buckwheat and rye. We put the same amount of Bokashi than what we harvest as grain »
  1. « The traditional japanese farms in the past had pigs staying on a mix of straw and manure and it didnt smell, no flies ! People lived with their livestock»
  1. « Wheat and rapeseed are undersownwith clover. When the crops are harvested, the clover can develop»


Some more information about the farm:


Crop Surface (ha) Yield (tonnes)
Wheat 2.37 5
Rice (human consumption) 1.3 5.2
Rice (for chickens) 2 5.1
Rapeseed 1.6 2
Buckwheat 4 1
Potatoes 70 ares 3
Soja 1.8 2.5
Rye 0.5 ha 3.6


Menno Village farm usesabout80% of organic fertiliser and the rest is chemical fertiliser. Chemical fertilizers are only used on the rice that will be used for chicken feed. Raymond usually put 600 kg/ ha of chemical fertiliser. They alsouse herbicidesfor weed control on the feed rice and one half of the rice grown for human consumption.


…bokashi has two useful features: One is fertilization. Another is that microorganism propagated through fermentation process enhances activities of plant roots. Microorganisms involved in fermentation include Rhyzopus, Koji mold (Asperllus orizae), Bacillus natto, Bacillus subtilis, Lactic acid bacilli, Yeast, Actinomycetes, etc. They generate organic acids, amino acids, vitamins, plant hormones; and activate enzymes and minerals. These actions are believed to enhance healthy crop growth. Microorganisms propagated in bokashi discourage activities of pathogenic fungi, bacteria and nematodes.


(extract from an article on http://www.jaec.org/jaec/english/2.pdf)

Questions for reflection in the classroom or at home

—> Those questions can be answered by the student alone or students can create little brainstorming group and lead their research like that. For this exercise students are free of using any other source of information/ any tool.

1.What are the natural processes involved in making it ?

2. What are the basic ingredients needed for this process to happen ? Explain the role played by each ingredient. Why water can be a problem?

3. Can you propose different reasons to explain the strong smell (sentence 1)?

4. Can you say – on average – what is the composition in NPK and carbon in bokashi ? Would you classify it as a fertiliser or a soil improvement product?

5. Which problems can happen from chicken manure use ? How to avoid that?

6. What is the gas produced when bokashi is turned over ? Do farmers need to take precautions?

7. Compare the amount of nitrogen brought bythe same quantity ofchemical fertilizer, the fermented chicken manure and the bokashi. Make a comment on your results

8. Based on your knowledge about what are the crops need for nitrogen, adapt your advice to Raymond: does he provide enough nutrients for his crops?

9. What do you think about the sentence written at the bottom of the fertiliser bag ?

10. With your knowledge (soillife web) and self research explains which organisms in soil life are present in bokashi.

11. Can you explain why few amount of Japanese farmers use bokashi ?What are the barriers to making bokashi?

13. Raymond is still using chemical fertiliser on some crops. Can you explain why?

Practice / get your hands dirty !


—> Some ideas for « learning by doing » or « learning with projects ». Those are only ideas, teachers and students can propose a lot of other ways to implement bokashi knowledge !

>> Describe the crop system of Menno Village with concepts and tools you learned in during your class. Can you describe the crop system according to the farm values and objectives?

>> Could you make Bokashi in your region? Why? Propose a recipeand make it.

>> Do you know a farmerin your areamaking something like bokashi ?

Interview him: why he makes it? What is the recipe? Compare the way it is done in Japan and in your place. Why is it different ?