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SIMO, PIMO, AIMO: New IMO Names, Moisture Ratios, Box Material

November 26, 2023 · by Drake Weinert

Dr. Drake and Master Lee spend the day at Master Lee's farm in Muju, Korea, running the whole IMO process in one sitting: collecting wild IMO from a winter greenhouse, adjusting leaf litter moisture, cooking rice for the box, and setting boxes into the litter under breathable rice-straw paper with 20cm or more of litter on top.

Master Lee introduces a new naming system so IMO1 and IMO2 are retired: the collected, sugared inoculant is now just seed IMO (SIMO). SIMO is propagated onto rice bran with FPJ, OHN, water-soluble calcium phosphate (WCAP, 1:1000), mugwort FPJ (1:500), brown rice vinegar (1:500), and 4 to 8 liters of seawater for minerals, at 0.1% SIMO by weight, to make PIMO. Good PIMO smells like a bakery; the batch that contacted soil and smells like forest leaf mold is the activated IMO, AIMO.

PIMO piles are built about 30cm high, mixed by hand or with a BCS tractor tiller for scale, and kept under 50 degrees Celsius since heat above 70 destroys the beneficial microbes; finishing takes about a week, with daily turning if it runs hot. AIMO is made by mixing PIMO with two soils (often red clay plus local soil) at roughly 50% PIMO, 25% soil, 25% soil.

The cycle continues past AIMO to feed IMO (FIMO, fed to animals), manure IMO (MIMO), and compost IMO, which Master Lee also touches on while checking a bag of chicken manure that, surprisingly, barely smells.

Questions answered

  • 17:29 What moisture percentage are we looking for in the IMO leaf litter? — Around 20-30%; too high, like 25% and up, starts turning the pile anaerobic.
  • 22:30 Are IMOs aerobic or anaerobic? — You cultivate aerobic microbes; anaerobic ones come along naturally, so don't chase them on purpose.
  • 28:36 What wood should the IMO box or basket be made from? — A cedar that's good for microbes works well, but some cedar species are antimicrobial and toxic, so check the tree first.
  • 33:41 Does heavily chlorinated municipal water affect the rice used to collect IMO? — Yes, it likely affects it, the same way chlorine and fluoride affect people.
  • 39:13 Is there a maximum depth for the leaf litter piled over the IMO box? — At least 20cm, but piling too high adds pressure and cuts off air to the microbes.
  • 44:02 Why drop the old IMO1/IMO2 numbering? — IMO1 always turns into IMO2 once sugared, so there's no separate stage; both are now just called seed IMO, SIMO.
  • 56:40 What's the typical ratio for using seawater as a mineral input? — Use about 4 to 8 liters of seawater per batch as the mineral source.
  • 59:07 Do you always use mugwort for the FPJ that goes into PIMO? — No fixed plant; mugwort or a similarly vigorous local plant like water dropwort works.
  • 1:02:11 Can you swap in plain water-soluble calcium instead of the calcium phosphate? — No, use the bone-derived water-soluble calcium phosphate (WCAP); the phosphorus makes it better for microbes than eggshell calcium alone.
  • 1:18:43 What's a common way people fail at making IMO? — Not being able to judge moisture and smell correctly, like when he first tried it in the Philippines and couldn't tell good IMO from bad by smell.
  • 1:36:56 Do you use a thermometer to track PIMO pile temperature? — A thermometer is precise, but you can learn to judge it by hand; keep it under 50 degrees Celsius since 70 destroys the good microbes.
  • 1:40:30 What's the mixing ratio for turning PIMO into AIMO? — Roughly 50% PIMO to 25% of one soil and 25% of another, such as red clay plus local soil.
  • 1:55:46 Is the red clay used for AIMO collected locally? — Yes, it's common all over Korea, and it's even used to filter and drink water for its medicinal qualities.
  • 2:18:20 How long does finished AIMO keep once it's dried and bagged? — Once dried the microbes go dormant, so it can keep for years until it's rewetted.

Topics: imo, simo, pimo, aimo, fpj, ohn, water soluble calcium phosphate, seawater, red clay, rice bran, moisture, cedar wood

KNF Office Hours is a free live Q&A every Sunday at 9 AM HST. Bring your question to pureknf.org/learn/questions or join live.

In this episode

  1. 0:00 Intro
  2. 0:29 Riding in the Back of Pastor Lee's Truck (Muju, Korea)
  3. 5:20 Collecting IMO in a Greenhouse in Winter
  4. 14:22 Adjusting Moisture of Leaf Litter
  5. 23:31 Preparing the Rice for the IMO Box
  6. 27:47 Choosing IMO Box and Basket Material
  7. 32:19 Filling the IMO Box with Rice
  8. 33:41 Does Chlorinated Water Affect IMO Collection?
  9. 34:13 Setting the Rice Boxes into the Leaf Litter
  10. 40:20 Smelling PIMO Made from Rice Bran
  11. 49:07 Making PIMO: Inputs and Ratios
  12. 1:07:24 Smelling and Judging PIMO Quality
  13. 1:15:00 Mixing FPJ, OHN, and Minerals into Rice Bran
  14. 1:29:00 Mixing the PIMO Pile with a BCS Tractor
  15. 1:32:38 Testing Moisture of Fresh PIMO
  16. 1:36:38 Caring for the PIMO Pile (Temperature, Turning)
  17. 1:40:30 Making AIMO: Mixing PIMO with Soil

Transcript

Auto-transcribed with Whisper. Click any timestamp to play from there.

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