Skip to content

Bacterial Cellulose Leather

Learning paths

Path Target Duration Skills
Discovery Kids 8 to 18 & 18 to 25 2 days learn and grow Kombucha

Introduction and context


“Fais pousser ton cuir !” is a 2 hours workshop addressed to children from 8 years old. Children learn about microorganisms and symbiosis, how to grow their kombucha “leather” and make a keyholder out of it.


The workshop is part of an initiative organized in collaboration with the University of Geneva and The Museum of Natural History about microorganisms and textile (La collaboration être humain et micro-organisms : pour une industrie textile plus durable”. The full programme includes a mini-expo, a 2 days workshop for adults and 4 workshops for children. Children will bring home a jar with a kombucha and a keyholder. However they won’t use the kombucha leather grown by themselves because that would mean to wait about 1 month (which is the approach we used for adults: a 2 days workshop with a 1 month gap)

The duration of the activity is 2 hours, including an explanation about microorganisms.

The ideal number of participants is 10. One instructor is enough but two instructors are ideal because the sewing part could be challenging for kids.


An introduction to microorganisms, symbiosis, fermentation and cellulose Mix the growing liquid for kombucha Use a sheet of kombucha leather cut and engraved with a laser cutter to make a keyholder

Target audience and context of use

Children from 8 years old. The workshop was organized in the context of an initiative dedicated to microorganisms and textile. The same activity can be adapted to adults and teenagers.

Preparation and materials

About 2 months in advance, grow the kombucha leather. The size of the sheet should be about A6 for each participant. About 1 week in advance, properly dry the leather. Prepare the tea in advance because it should be at room temperature when used Prepare the keyholder shapes to be assembled. Prepare a keyholder to show the final result.

Prepare a room with big tables and access to water. A beamer might be useful to show examples of clothes and accessories made with kombucha leather and the “recipe”.

Prepare each post with:

1st part: - Glass jars - Graduated containers - Balance

2nd part: - Needle with a big shank - Thick thread - Metal key ring - Keyholder shape

Create a team of facilitators and organize a testing session.

Equipment, Tools and Materials

  • Laser cutter (to be used in advance to prepare the keyholder to be assembled)
  • Inkscape or an equivalent software for 2d modeling and vectoral drawing.
  • Glass jar about 750 ml
  • A small kombucha mother
  • Tea 700 ml (room temperature)
  • Sugar 70 gr
  • Vinegar 10 ml
  • Starter (the liquid of culture of the kombucha mother) 10 ml
  • Spoon
  • Plastic film
  • Pre-cut and engraved leather keyholder shape
  • Needle with a big shank
  • Thick thread about 1 m
  • Metal rings for key-holder
  • 3 kitchen scales
  • 3 graduated containers

Step by Step Instructions

STEP BY STEP overview

  • Mix the tea with the sugar in a glass jar. Tea should be at room temperature (20-30 °C)
  • Add vinegar and the liquid starter
  • Thoroughly mix the ingredients. (To obtain more culture liquid, simply multiply the doses of ingredients)
  • Add the kombucha mother
  • Close the jar with a plastic film
  • Put the growing liquid and the kombucha mother in a shallow recipient and cover it with plastic film to avoid flies – attracted by sugar and vinegar - to lay eggs in your mix.
  • Put the container in a dark place; room temperature should be around 25 °C. If colder, the kombucha will grow slower.
  • After a week, a whitish film will appear on the surface of your container
  • Let the kombucha grow for at least 1 month.
  • Wash the kombucha leather with soap and cold water
  • Dry the kombucha leather on a leaned wooden board for a few days
  • Laser cut and engrave the kombucha leather using the attached vectoral file.
  • Laser cut the holes to help children sewing
  • Insert the metal ring for keyholder
  • Fold the shape
  • Sew the keyholder with blanket stitch

Note: Steps 1 to 4 were not done during the workshop and participants received the instructions to grow the kombucha at home. However, it is possible to organize a workshop in 2 sessions, with a 6 weeks gap.

Safety rules & Tips


Flyer for participants

This browser does not support PDFs.

Tips to facilitate the activity in context (to-do / not do)

To do: Make through in any laser cut pattern you’d like to use to facilitate the sewing task Make sure to have enough time to grow the kombucha (otherwise it will be too fragile) Make sure to have enough time to dry the kombucha leather (otherwise it will be sticky) Keep the lids of the jars if participants are leaving with their liquid of culture

Not to do: Use needles with a small shaft

Estimated cost
... Always consider to find local providers.

Item Quantity Cost (€) Link to vendor
Teabag 3 1 Local store
Kombucha mother 10 0 ask around your community
Sugar 1kg 3 Local store
Vinegar 0.1 0.5 Local store
Glass jars or plastic trays 10 20 Local store
Spoons 10 3 Local store
Plastic film 1 3 Local store
Needles with a big shank 10 3 Local store
Thick thread 10 m 5 Local storeh
Metal rings for keyholder 10 15


Links to photos and recorded materials

Licence and credits

Attribution — ShareAlike CC BY-SA This activity has been designed by Anastasia Pistofidou and Cristina Olivotto for

Related and supporting activities/modules
It can be combined with the other topics of Topic/skills, part of ...

Last update: December 23, 2022