Do you know the benefits of human urine? Don’t hesitate — it’s like liquid gold, a natural manure that’s freely and abundantly available. From ancient times, farmers have understood the value of animal excreta in farming. Cow dung, sheep droppings, and poultry manure have long been used as natural fertilizers to enrich the soil. But interestingly, human excreta—especially urine—is even richer in nutrients.
Humans consume diverse, nutrient-rich foods like grains, vegetables, fruits, and herbs, which makes their excreta highly nutritious. That’s why scientists and traditional farmers alike call it “gold manure.”
Unfortunately, because of hygiene concerns, human feces are not used in farming today. But human urine, which is sterile when fresh, can be safely used as a liquid fertilizer after simple treatment.
Traditional Use of Human Urine
In the olden days, before modern toilets became common, people used to collect urine in earthen or metal vessels at night.
Next morning, they would mix it with household wood ash, which helped to reduce odor and preserve nutrients.
The mixture was then kept covered for a few days and later used on crops.
In some rural areas even today, farmers use this urine mixture to treat bud rot disease in coconut palms and also as a tonic for banana and arecanut plants.
This shows that our ancestors had deep scientific understanding of natural recycling, even without formal education.
Nutrient Contents in Human Urine
Human urine contains all three major plant nutrients—Nitrogen (N), Phosphorus (P), and Potassium (K)—in soluble form.
Typical nutrient values are:
- Nitrogen (N): 0.5% to 1%
- Phosphorus (P₂O₅): 0.1%
- Potassium (K₂O): 0.3% to 0.5%
It also contains Sulphur, Calcium, Magnesium, and micronutrients like Iron, Zinc, and Boron.
These nutrients are similar to what chemical fertilizers provide, making urine a complete natural fertilizer.
Absorption and Action in Plants
Since all nutrients in urine are dissolved, they are immediately available to plants after application.
- Nitrogen helps rapid leaf growth.
- Phosphorus and potassium improve root strength, flowering, and fruit quality.
Thus, plants respond quickly after urine application, showing visible greenness within a few days.
Fungicidal and Pest Control Properties
Fresh human urine contains ammonia, which gives it mild fungicidal and antibacterial power.
- When diluted and sprayed, it can help control early fungal infections on leaves.
- It is also known to discourage soft-bodied insects like aphids and mealybugs.
Because of these properties, farmers in some areas used it as a natural disinfectant for soil and plants.
How to Make Human Urine Odorless
Untreated urine develops a strong odor when urea breaks down into ammonia. Simple methods can make it odorless and safe:
- Collect urine in a covered vessel or tank.
- Add wood ash, lime, or jaggery water (1–2%) to control odor and preserve nitrogen.
- Keep closed for 10–15 days for mild fermentation.
- Dilute before use: Mix 1 part urine with 5–10 parts water and apply near the root zone.
This process not only reduces smell but also prevents nitrogen loss and enhances its effect on crops.
Public Toilets and Urine Collection
Modern urine-diverting eco-toilets can separate urine from feces, allowing safe collection in public places, schools, or offices.
The stored urine can be treated and used as liquid fertilizer for agriculture, gardens, and plantations.
Several pilot projects in India (Auroville, Tamil Nadu) and abroad (Sweden, Finland) have successfully demonstrated the safe and large-scale use of human urine as manure.
Commercial Research and Results
Scientific studies show that crops like maize, cabbage, and banana grown with treated human urine produce yields equal to or higher than chemical fertilizers.
Research also reveals that urine from one adult per year can supply enough nutrients to grow food for one person for an entire year — proving its high value as a renewable nutrient source.
Precautions
- Always dilute before applying to avoid leaf burn.
- Avoid using urine from sick or medicated persons.
- Do not spray directly on edible parts of the plant.
- Use clean containers and follow hygienic handling.
Conclusion
Human urine is a powerful, free, and eco-friendly fertilizer that can reduce dependence on costly chemical inputs.
Our ancestors already knew its value and used it wisely by mixing with ash and fermenting before use.
With modern scientific understanding and safe collection systems, this “gold manure” can once again play a vital role in sustainable farming and soil fertility restoration.
