Part 1 introduces soil fertility improvement materials approved in organic agriculture under PGS Standards. A = Allowed; R = Restricted, must be approved by PGS before use.
Part 1: Inputs for Soil Fertility Improvement
Conditions for using fertilizers and soil improvement materials
| Inputs | A/R | Details and conditions |
|---|---|---|
| Animal manure | R | All animal manure must be hot-composted or thoroughly dried before use. Do not use manure from commercial feedlots; manure from household-raised livestock or free-range animals may be used if treated in accordance with regulations. |
| Wood ash | R | Only use wood ash as a potassium source. It should be used regularly in small amounts, stored covered, and mixed with finished compost to avoid raising soil pH. |
| Compost | A | Materials should be collected on-farm; do not use municipal waste. Rice straw, rice husks, green foliage, animal manure, and coffee husks can be supplemented from outside. The compost pile must reach above 60°C for 8–15 days and be turned when it begins to cool. |
| Biofertilizer | R | Only use products approved by PGS; microbial fertilizers derived from peat are prohibited. |
| Mineral fertilizer | R | Only use certified or approved sources and for supplementary purposes only; rock phosphate must be finely ground before application. |
| Sedimentary rock | A | Used as a soil supplement when needed. |
| Limestone | A | Used as a soil supplement when needed. |
| Rice husks | A | Used as mulch or composting material to retain nutrients. |
| Straw, stubble | A | Used for composting or soil mulching. Livestock bedding straw must be hot-composted before application to the fields. |
| EM (Effective Microorganisms) | A | Liquid EM is permitted for use. |
| Micronutrients | R | Prioritize natural mineral sources. Use synthetic nutrients only when plants and soil show clear signs of deficiency; do not use nitrate or chloride. |
| Leguminous plant materials | A | Leaves and branches of legumes such as Sesbania, coral tree, pinto peanut, senna, and pigeon pea can be used for mulching around plant bases or composting. |
| Mushroom cultivation substrate | R | Only use when the substrate has not been treated with fungicides to eliminate spores. |
| Molasses | A | Used when composting green materials as a food source for microorganisms. |
| Worm castings, vermicompost granules, and worm tea | A | Prioritize raising worms on plant waste. Worm castings can be applied directly, or one liter of worm liquid can be diluted with 10–20 liters of water for watering. |
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