Knowledge Base

Yeast Culture

Microbial culture · Master Cho · KNF

Wild yeast cultured off fruit skins — the finisher of fermentation that rebuilds vitamins, hormones and vigor in weak or storm-hit plants.

All stages
Moderate to make
7–30 days ferment
1:1000 dilution
enzymes, vitamins, hormones supplied
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Dilution 1:1000

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Ingredients

  • Grapes or strawberries (unwashed, yeast-rich skins)as available culture medium

How to make it

  1. Step 1

    Choose ripe grapes or strawberries — yeast lives on the skins. Do NOT wash; use as they are.

  2. Step 2

    Sterilize all tools before use to keep out unwanted microbes.

  3. Step 3

    Place the fruit in a container on its own, away from other cultures and odors.

  4. Step 4

    Cover loosely with the lid — never seal the container.

  5. Step 5

    Hold at 23–25°C and 65–70% humidity for the culture to thrive.

  6. Step 6

    Shake 1–2 times a day to protect the yeast from fungi.

  7. Step 7

    Refrigerate the cultivated yeast at 1–15°C once ready.

What it is

Yeast is the microbe in charge of the last step of fermentation, breaking sugars into alcohol and carbon dioxide. It resynthesizes decomposed organic matter into amino acids, hormones and vitamins, and produces minerals, nucleic acids and fatty acids that plants and animals cannot make themselves. Wild yeast clings to fruit skins — grapes especially — so ripe fruit is the culture medium.

On the Nutritive Cycle: Yeast is an all-stages backbone. It enhances metabolism and can be reached for whenever a crop or animal needs to rebuild vigor — a repair tonic more than a stage-specific feed.

When to use it

  • Weak plants — spray to restore vigor.
  • Disease — when viral or bacterial disease appears.
  • Storm damage — when strong wind has heavily damaged branches or stems.
  • Low light — during rainy or high-humidity seasons when photosynthesis is low.
  • Livestock — when animals lose appetite or vigor.

Dilute 1:1000 and spray on leaves together with other Natural Farming materials.

Materials

  • Ripe grapes or strawberries, unwashed (yeast-rich skins)
  • A clean container with a loose lid, kept apart from other cultures
  • Sterilized tools

How to make it

  1. Pick yeast-rich fruit. Grapes or strawberries; do not wash — use as they are.
  2. Sterilize tools before starting to keep out unwanted microbes.
  3. Isolate the jar. Keep it separate so stray microbes and odors can't get in; cover loosely, never seal.
  4. Hold conditions. Keep 23–25°C and 65–70% humidity.
  5. Shake daily 1–2 times to protect against fungi during cultivation.

Signs it worked / troubleshooting

  • Good: a lively ferment with a clean, fruity-alcoholic smell.
  • ⚠️ Fungus forming = not shaken enough → shake 1–2 times daily.
  • 🚫 Off, contaminated smell = stray microbes got in → discard and restart with sterilized tools.

How to store

Refrigerate the cultivated yeast at 1–15°C. It keeps a maximum of one month, but it is best to use it all within a week.

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