Credit: iStockphoto
LONDON: Using human urine as a fertiliser produces bumper crops of tomatoes that are safe to eat, scientists have found.
Their research was published last month in the Journal of Agricultural and Food Chemistry and may help cheaply boost crops in the developing world.
Surendra Pradhan, an environmental biologist at the University of Kuopio, in Finland, and her team gave potted tomato plants one of three treatments: mineral fertiliser, urine and wood ash, urine only, and no fertiliser. Urine is rich in nitrogen, phosphorus and potassium.
Safe for consumption
Yields for plants fertilised with urine quadrupled and matched those of mineral-fertilised plants. The urine-fertilised tomatoes also contained more protein and were safe for human consumption.
"This is a very simple technology. Urine can be collected in a urine-diverting toilet or it can be collected in a separate jerry can [from] an ordinary, pre-existing toilet. If wood ash is available, this can be use as a supplement of phosphorus, potassium and other nutrients," Pradhan said.
He added that the method is a free alternative to expensive mineral fertiliser, which is also not easily available in remote or hilly areas.
Pradhan also believes that the idea could improve sanitation by incentivising toilet-building. A pilot program based on the research will be launched in Nepal in November.
Problems of scale
But Håkan Jönsson, eco-agriculture and sanitation system technology expert at the Stockholm Environment Institute in Sweden, wasn't sure how practical the method would be for commercial farms.
"The amount [of urine] that can be collected from a person or a family is fairly small and equivalent to about two bags of fertiliser per year for a west African family," he said. "[The technique] is of great value to a subsistence farmer but does not suffice for even a medium-scale cash-crop farm."
To fertilise larger areas, many urine-diverting toilets would have to be linked up to a good transportation system, he said.
When the culture is an impediment to progress...
change the culture.
Tomatoes thrive on urine
I tested the idea on 4 Black Russian tomato planes, 3 weeks old and about 100mm high with top picked out. All plants were wide, bushy and healthy, living in 6.5 soil with blood and bone recently added, lime about 10 days earlier.
To omit container contamination I urinated directly on one of the three plants. 7 days later it is wilting and clearly dying.
Could be my urine, a fault in the original research, or someething about Russians.
Has anyone else tested the idea?
Have to know your stuff
Urine on Foliage will kill most plants.
Urine on soil for root uptake is exellent, for tomatoes.
Tomatoes thrive in acid soil, adding lime moves the ph in the completely opposite direction.
Better luck next time.
Tomatoes thrive(?) on urine
I just tried it on one of five healthy plants just transplanted from pots. As above, I used the direct approach. I did not aim for the foliage, but rather the ground around the plant, but some foliage must have gotten a dose, because this plant began wilting within 12 hours, and was dead a week later.
Dilution is key!!
although they didnt specify in this article... You need to dilute it 10 or 15 to 1 because the urine is too strong if you feed your plants with it directly...
it should work REALLY WELL once you dilute the urine :)
I'd go to jail
If I did that in our community garden, across from my building and next to the church, they would lock me up.
Then again, my friend uses his carp pound water to water his tomatoes, he has so many they they are rotting away.
Must be the urine turns into a sort of ammonia, which supplies nitrogen. Also known as Ammonia-nitrate, a fertilizer.