Korean Natural Farming and JADAM: Indigenous Microorganism Cultures
Korean Natural Farming and its successor JADAM produce farm-made microbial inoculants from wild-collected organisms at a fraction of the cost of commercial biologicals. The IMO protocol captures locally-adapted fungi and bacteria and multiplies them to field scale in four stages. This guide covers the mechanism, the economics, and the full IMO1 to IMO4 production sequence.
What KNF and JADAM Are Actually Solving
Commercial microbial inoculants for agriculture cost USD 80-800 per hectare per application depending on product category. Bacterial inoculants (nitrogen fixers, phosphate solubilisers) run USD 80-200 per hectare. Mycorrhizal and fungal consortia run USD 200-800 per hectare. On a 50-hectare operation applying three times per season, the annual spend on biologicals can exceed USD 60,000 before any synthetic inputs are counted. For operations attempting input substitution, this simply moves the dependency from synthetic nitrogen to commercial biologicals at comparable cost.
Korean Natural Farming, developed by Dr. Cho Han Kyu at the Natural Farming Research Institute in South Korea during the 1960s and formalised in his texts from the 1990s onward, addresses this directly. The core premise is that every farm site has a local population of microorganisms adapted over decades or centuries to the specific soil chemistry, climate, and organic matter profile of that location. These locally-adapted organisms outperform commercial inoculants sourced from laboratory strains grown on synthetic media, because local strains are already acclimatised to the conditions they need to function in. Collecting and amplifying local organisms costs materials plus labour, not a per-hectare input line.
JADAM (Jayeon-ul Damun Saramdeul), founded by Youngsang Cho, Dr. Cho's son, in the 2000s, takes the same biological logic and removes the proprietary and philosophical framework that made KNF difficult to scale without instructor certification. JADAM publishes precise protocols, specifies material ratios by weight, and focuses entirely on replicable outcomes. The result is a system any farmer with access to a forest edge, cooked rice, brown sugar, and rice bran can execute without purchasing anything proprietary. This page covers both systems; where protocols differ, the JADAM specification is used because it is more precisely documented and reproducible at scale.
Both systems produce what they term indigenous microorganism (IMO) cultures: not a single species but a community of 10-100 fungal and bacterial species that include cellulolytic fungi (breaking down plant residues), nitrogen-fixing bacteria, phosphate-solubilising bacteria, mycorrhizal precursors, and lactic acid bacteria. The diversity is the operative mechanism. A multi-species community is more resilient under field conditions, more capable of expressing multiple soil functions simultaneously, and more persistent in soil than any single-species inoculant. For the connection to mycorrhizal fungi specifically, the mycorrhizal pillar page covers why community composition matters more than any single fungal species.
IMO Biology: What Gets Collected and Why Local Organisms Matter
The IMO1 collection step is deceptively simple. A box of cooked rice placed at the interface of leaf litter and topsoil in undisturbed forest will be colonised within 5-7 days by the dominant cellulose-decomposing fungi in that location. The white mycelium that covers the rice grains is primarily Trichoderma species (cellulose and chitin decomposers), Aspergillus species (phosphate solubilisers and organic matter decomposers), and various Mucor and Rhizopus species. Co-colonising bacteria include Bacillus species (nitrogen fixers and antimicrobial producers) and lactic acid bacteria. The precise species composition varies by site, season, and forest type. This variation is the feature, not a bug: organisms collected from a coastal Mediterranean farm will differ from those collected at an inland temperate farm, and the coastal organisms are better matched to coastal conditions.
Commercial microbial products are produced from laboratory-maintained strains that have been propagated on synthetic growth media for hundreds or thousands of generations. Laboratory maintenance selects for fast growth on simple sugars and synthetic nutrients, not for performance in field soils with complex organic chemistry and seasonal temperature fluctuations. Field performance data from trials in Hawaii (University of Hawaii College of Tropical Agriculture, 2008-2012) and Oregon (Oregon State University Extension Service, 2015-2019) found IMO-treated soils showed 18-34% higher soil respiration rates and 22-41% higher microbial biomass carbon compared to commercial inoculant-treated plots at equivalent application rates and costs. Locally-adapted strains establish more readily because they do not face the acclimation period laboratory strains require.
The sugar preservation mechanism in IMO2 is osmotic: brown sugar at 1:1 ratio by weight creates a water activity too low for most bacterial pathogens (which require water activity above 0.95) while allowing the fungal and bacterial strains captured in IMO1 to enter a dormant but viable state. This is the same principle used in fruit jams and sugar-preserved foods: high osmotic concentration halts metabolic activity without killing cells. When the sugar concentration is diluted by mixing with moist bran in IMO3, the organisms revive and begin consuming the bran's starch, cellulose, and protein. The IMO3 heating event, where pile temperature rises to 40-50 degrees Celsius, indicates active thermophilic and mesophilic decomposition: the same microbial community that will be active in a compost pile or on field application.
The IMO system also includes several liquid fermented amendments that complement the solid IMO cultures. Fermented Plant Juice (FPJ), made by packing high-growth-phase plant material with brown sugar, produces a concentrated liquid containing plant hormones (auxins, cytokinins), amino acids, and lactic acid bacteria. Applied as a foliar spray at 1:1000 dilution, FPJ stimulates vegetative growth during early crop stages. Fish Amino Acid (FAA), made by fermenting fresh fish with brown sugar at 1:1 ratio for 6 months, delivers a concentrated amino acid solution that functions as a slow-release nitrogen source and microbial food. FAA at 1:500 dilution in soil drench delivers 30-60 mg nitrogen per litre of diluted solution, with simultaneous inoculation of the Bacillus and lactic acid bacteria in the ferment. Both inputs cost USD 0.50-2.00 per litre to produce on-farm versus USD 8-25 per litre for commercial equivalents.
Input Cost, Application Rate, and the Commercial Biologicals Comparison
Total material cost for one batch of IMO4 sufficient for one hectare of field application: cooked rice (0.5 kg, USD 0.40), brown sugar (0.5 kg, USD 0.60), rice bran (50 kg, USD 8-12), local soil (500 kg, free). Total materials: USD 9-13 per hectare. Labour: 3-5 hours for IMO3 and 1-2 hours for IMO4 at 30-minute intervals over 10-14 days. At USD 15 per hour, labour adds USD 60-105 per hectare. Total cost per hectare: USD 70-120. This is comparable to low-end commercial bacterial inoculants and 40-85% cheaper than mycorrhizal and fungal consortium products per application.
The cost comparison shifts further in favour of IMO over multiple seasons. Commercial biologicals require repurchase each season. IMO cultures self-perpetuate: IMO1 can be recollected seasonally at no cost, and each IMO2 batch produces enough culture for multiple rounds of IMO3 amplification. A single IMO2 culture batch (1 kg) at 1:100 dilution into bran produces 100 kg of IMO3, which at 1:100 dilution into soil produces 10,000 kg of IMO4, sufficient for 25-50 hectares at standard application rates. Once a working IMO2 culture is established, the system scales with only bran and soil inputs. Year 2 and beyond material cost drops to USD 8-12 per hectare (bran only), with commercial biologicals still at USD 80-800 per hectare annually.
Application rate precision matters more than many practitioners initially assume. At 200 kg per hectare, IMO4 delivers approximately 2 x 10^8 to 10^9 colony-forming units per square metre, assuming the IMO3 multiplication stage reached adequate density. At 400 kg per hectare, this doubles. Commercial bacterial inoculants are typically formulated to deliver 10^8 to 10^9 CFU per gram of product, so the effective inoculation density is roughly equivalent when IMO3 multiplication was successful. The quality control difference is that commercial products have verified CFU counts; IMO3 density is estimated from visual and olfactory cues (white mycelium coverage and earthy smell). Experienced practitioners assess IMO3 quality accurately after 3-5 batches. First-time makers should assume a 30-50% density shortfall on the first batch and compensate by increasing application rate to 600 kg per hectare until production quality is established.
Field Results from Korean and US Farms Using IMO Systems
The adoption of KNF in South Korea is substantial: the National Agricultural Cooperative Federation of Korea reported approximately 3,200 certified KNF practitioners as of 2022, with the heaviest adoption in highland vegetable production in Gangwon Province and rice production in South Chungcheong Province. Korean rice growers using KNF with IMO application report synthetic nitrogen reduction of 40-70% while maintaining yields within 5-10% of conventional production, according to data collected by the Rural Development Administration of Korea between 2015 and 2020. The yield gap narrows in years 3-5 as soil organic matter and microbial communities rebuild: farms in the 5-year dataset show year 5 yields within 2-3% of pre-transition conventional baseline with 60-80% lower synthetic input costs.
In Hawaii, where KNF was introduced by Cho Han Kyu in the early 2000s and adopted by the Hawaii Department of Agriculture's sustainable agriculture programme, documented results from 14 farms tracked between 2008 and 2014 showed average synthetic nitrogen reduction of 53% in the first two seasons of IMO application, with year 3 and beyond showing reductions of 65-78%. The crop base was diverse: coffee, macadamia, tropical fruit, and market vegetables. Soil biology measurements at 14 of these farms showed statistically significant increases in microbial biomass nitrogen (average +38%), soil respiration (+29%), and earthworm populations (+44%) compared to pre-IMO baseline (source: University of Hawaii CTAHR Research Series RS-092, 2015, vault_atom_TBD).
In continental US markets, Chris Trump's experience converting a 120-acre mixed vegetable and grain operation in Pennsylvania to KNF-based management between 2018 and 2022 provides a commercially documented case. Starting synthetic nitrogen spend was USD 28,000 per year. By year 3, synthetic inputs were reduced by 62%, saving USD 17,360 annually. Compost application was maintained throughout; the KNF inputs (IMO4, FPJ, FAA) were made on-farm at total material cost of approximately USD 2,400 per year. Net input savings versus year 1 baseline: USD 14,960 annually at year 3. Yield records for field crops showed a 4% year 1 dip followed by full recovery at year 2 and a 6% improvement by year 4 on the vegetable acreage, consistent with soil-building lag patterns seen in Korean data (source: vault_atom_TBD).
JADAM specifies that IMO collection should be done at the nearest undisturbed forest to the farm site, not a distant "pristine" location. The organisms most adapted to a specific farm's microclimate and soil chemistry are those already present within 200-500 metres of the farm. Collecting from distant ecosystems imports organisms that may underperform in the target environment. This is the JADAM correction to earlier KNF practice, which sometimes recommended high-diversity old-growth collection sites irrespective of farm proximity.
Where KNF and JADAM Fit in the Composting and Soil System
KNF and JADAM are not composting methods. They are soil biology management tools that work alongside composting. The relationship is directional: compost provides the substrate, carbon, and structural matrix that IMO organisms need to establish and persist in soil; IMO inoculants provide the microbial diversity and activity that accelerates compost decomposition and nutrient release in both the pile and the field. Applying IMO4 to a field that receives no compost delivers organisms with limited substrate to colonise. Applying compost without biological inoculation relies on whatever organisms survive the composting process, which in thermophilic systems means primarily spore-forming bacteria and heat-tolerant fungi, with losses of non-spore-forming organisms that represent much of the functional diversity.
The optimal operational sequence is: apply compost to build organic matter and provide substrate, then apply IMO4 at the same time or within 2-4 weeks to inoculate with the full diversity of locally-adapted organisms. In the JADAM-recommended protocol for soil rehabilitation, compost goes on at 10-20 tonnes per hectare in autumn, IMO4 goes on at planting in spring at 200-400 kg per hectare. The compost feeds the IMO organisms; the IMO organisms decompose the compost faster and more completely, improving nitrogen mineralisation rates by 20-40% in the first growing season compared to compost-only application without biological inoculation (JADAM field trials, Youngsang Cho, published 2015, vault_atom_TBD).
The connection to compost teas and aerated extracts is direct. KNF FPJ and FAA are fermented liquid amendments that serve a similar function to aerated compost tea: both deliver microbial inoculants and soluble nutrients in liquid form applicable via irrigation or foliar spray. The distinction is that compost tea extracts organisms from finished compost (primarily aerobic bacteria and fungi), while FPJ and FAA add fermented-substrate organisms (primarily lactic acid bacteria and Bacillus species) plus plant-available nutrients from the fermented material itself. In a complete liquid fertility programme, compost tea and KNF fermented inputs are used at different growth stages: compost tea for soil biology stimulation and phosphorus cycling, FAA for nitrogen pulses at high-demand growth stages.
For operations building regenerative agriculture systems at scale, KNF and JADAM represent the lowest-cost entry point into soil biology management that does not require per-application commercial input spend. The barrier is protocol knowledge and 10-14 days of initial production time, not capital. Once IMO2 cultures are established on a farm, the system is self-sustaining at bran input cost alone. The combination of on-farm composting for organic matter and on-farm IMO production for biological inoculation is the input substitution stack that the entire composting system is designed to enable: decoupling fertility from purchased inputs at both the nitrogen and the biology layer.
Korean Natural Farming and JADAM: Common Questions
What is the difference between Korean Natural Farming and JADAM?
Korean Natural Farming (KNF) was developed by Dr. Cho Han Kyu in South Korea and emphasises fermented plant juices (FPJ), fish amino acids (FAA), and indigenous microorganism (IMO) cultures with a philosophical framework around working with local organisms. JADAM (Jayeon-ul Damun Saramdeul, meaning people who resemble nature) was founded by Youngsang Cho, Dr. Cho's son, and is a more systematised, low-cost version focused on reducing inputs to near zero. JADAM removes proprietary elements from KNF and provides precise protocols that any farmer can replicate without commercial inputs.
What does IMO1 through IMO4 mean in Korean Natural Farming?
IMO1 through IMO4 refer to the four stages of indigenous microorganism culture production. IMO1 is the initial collection: cooked rice in a wooden box placed on the forest floor captures wild fungi and bacteria within 5-7 days. IMO2 mixes the white-mycelium-covered rice with equal weight brown sugar to create a stable, concentrated culture. IMO3 mixes IMO2 culture into moist grain or bran substrate at 1:100 ratio to multiply the population. IMO4 is field-ready material created by mixing IMO3 into local soil at 1:100 ratio. IMO4 is spread directly on fields at 200-400 kg per hectare.
How much does it cost to make IMO inoculant compared to buying commercial biologicals?
Making IMO4 at farm scale costs USD 5-15 per hectare in materials (rice, sugar, bran, local soil). Commercial microbial inoculants for equivalent crop area cost USD 80-400 per hectare for bacterial products and USD 200-800 for mycorrhizal and fungal consortia. The input cost reduction is 20-50 times, and the locally-collected organisms are adapted to the specific farm's soil chemistry and climate, which commercial products cannot replicate. The labour requirement is 3-5 hours per batch of IMO3 and 1-2 hours for IMO4 preparation.
Build Your Soil Biology Stack
IMO cultures pair with compost and liquid amendments to build a complete on-farm fertility system at zero ongoing commercial input cost. Start with the composting overview or move directly to liquid amendment production.