Human Journey

Human Pee Added to Compost Boosts Crops

Discarded food atop a compost pile at an organic farm. Photograph by Hannele Lahti, National Geographic

 

People have been using manure as fertilizer for millennia. But scientists now believe they can turn human urine into liquid gold—as composting material. 

The premise is simple: Pee is rich in nitrogen, which plants desperately need. Commercial fertilizers boost plant growth and yield by providing abundant nitrogen to the plant’s roots.

Of course, commercial fertilizers can harm the environment if they get into lakes and streams. As well, not all farmers in the developing world can afford to buy fertilizer for their crops. Enter pee. (Related: “Human Pee With Ash Is a Natural Fertilizer.“)

Debendra Shrestha, a researcher at Tribhuvan University in Kathmandu, Nepal, noted that Nepalese farmers have been applying human urine to their crops for centuries.

Unlike commercial fertilizers, urine is free and abundantly available. Plus, it doesn’t seem to have any harmful environmental effects. The main question that remained was whether it actually worked: Would plants grow better when their soil was treated with human urine?

Pee Power

To answer this question, Shrestha and colleagues grew sweet peppers (Capsicum annum) in soil that had various combinations of human urine, compost, and urea—the main nitrogen-containing chemical in human urine. The urine was collected from communal toilets in Kathmandu, whereas the compost was sourced from cow manure. (Also see “Urine Battery Turns Pee Into Power.”)

The plants grown in soil that had a combination of human urine and compost grew the tallest, yielded the most peppers, and had the most total fruit weight per plant, according to the study, published recently in the journal Scientia Horticulturae.

The scientists say the pee was so effective because of several factors working together. For instance, the mix of compost and urine decreased the amount of nitrogen lost in the soil while making more carbon available to the plants.

“We need to start moving toward the application of urine in combination with compost,” Shrestha said in an interview with <a ” href=”http://www.scidev.net/en/south-asia/news/crop-thrives-on-urine-compost-mix.html” target=”_blank”>SciDev.Net.

To Pee or Not to Pee?

Still, not everyone is convinced. Other studies in Africa that used a combination of human urine, human manure, and poultry manure found that these substances did not yield more crops than commercial fertilizers did. (See “Human Waste to Revive Haitian Farmland?”)

The use of human urine, noted Surendra Pradhan, a researcher at the International Water Management Institute who is based in Ghana, has major problems, according to SciDev.Net.

For one, although urine is freely available, not all cultures might take to the idea of using it on their crops. What’s more, it needs to be used along with compost for it to be effective, since urine alone doesn’t have enough nutrients to sustain plant growth over several years. (Read more about sustainable agriculture.)

Last, although commercially available fertilizers aren’t free, many governments do subsidize their availability, which may decrease the overall appeal of urine-based fertilizers.

Carrie is a freelance science writer living in Virginia. When she's not writing about cool critters, she's spending time outside, drinking coffee, or knitting. You can visit her website at http://www.carriearnold.com
  • Tom Key

    What about the high salt content in pee?

    Human and animal “waste products” should not be wasted. Each person has a daily and incredible ability to convert complex products into usable soil.

  • Tom Key

    What about the high salt content in pee?

    Human and animal “waste products” should not be wasted. Each person has a daily and incredible ability to convert complex products into usable soil.

  • karthi

    i like it

  • karthi

    i like it

  • Gayath Indika Senarath Pathirana

    COMPOST IS BEGIN OF THE ORGANIC CULTIVATION.WE HAVE TO HELP FOR FARMERS.
    GAYATH.

  • Anna Anchala

    Long a practice in the United States. Human urine is used in various ways to enrich soil and grow plants.
    Check out the fun book, Liquid Gold: The Lore and Logic of Using Urine to grow plants. June 21 is “Pee-On-Earth Day.”

  • Anna Anchala

    Long a practice in the United States. Human urine is used in various ways to enrich soil and grow plants.
    Check out the fun book, Liquid Gold: The Lore and Logic of Using Urine to grow plants. June 21 is “Pee-On-Earth Day.”

  • homer

    Seriously ur barely taking this into consideration???slow ass ppl this is logic

  • homer

    Seriously ur barely taking this into consideration???slow ass ppl this is logic

  • Chudamani Akavaram

    As a child I used to find in the house of my grandfather and other relatives that human waste like urine and faeces was dumped on the garbage depositswhichconsisted mainly of animal and vegeteble wastes was allowed to decay and formed into compost. Earth worms and other insects played a significant role in converting the whole mass into a wonderful manure. Yesteryears’ waste material thus formed into present years’ bonanza for the crops.

  • Chudamani Akavaram

    As a child I used to find in the house of my grandfather and other relatives that human waste like urine and faeces was dumped on the garbage depositswhichconsisted mainly of animal and vegeteble wastes was allowed to decay and formed into compost. Earth worms and other insects played a significant role in converting the whole mass into a wonderful manure. Yesteryears’ waste material thus formed into present years’ bonanza for the crops.

  • Tom Jarvis

    I regularly piss over my plants every night and there is an amazing difference in the growth rate of the ones I piss on and the ones I don’t !
    So don’t just talk to your plants piss on them too 🙂

  • Tom Jarvis

    I regularly piss over my plants every night and there is an amazing difference in the growth rate of the ones I piss on and the ones I don’t !
    So don’t just talk to your plants piss on them too 🙂

  • Stella H Howell

    Every human beings excreta is different.
    We are what we eat (besides other things).
    Medication, drugs, consumption of thrash foods including flesh & blood results in putrefied excreta, this is because ones internal organs are diseased in the stage of cancerous.
    Therefore purchasing compost particularly recycled compost is certainly not a good idea.
    In days of old, people were vegans and used their own household excreta on their own soil.

  • Stella H Howell

    Every human beings excreta is different.
    We are what we eat (besides other things).
    Medication, drugs, consumption of thrash foods including flesh & blood results in putrefied excreta, this is because ones internal organs are diseased in the stage of cancerous.
    Therefore purchasing compost particularly recycled compost is certainly not a good idea.
    In days of old, people were vegans and used their own household excreta on their own soil.

  • bahbcat

    Thos “commercial fertilizers” are largely cow piss. And wet pies.

    A little Urea on the veggie waste helps it cook faster.

  • bahbcat

    Thos “commercial fertilizers” are largely cow piss. And wet pies.

    A little Urea on the veggie waste helps it cook faster.

  • bahbcat

    Those “commercial fertilizers” are largely cow piss. And wet pies.

    A little Urea on the veggie waste helps it cook faster.

  • bahbcat

    Those “commercial fertilizers” are largely cow piss. And wet pies.

    A little Urea on the veggie waste helps it cook faster.

  • Raul

    That’s the mistery of human body. Pee has a lot of Nitrogen needed by the plants similar to fertilizers. Old folks in rural areas already know about this long ago.

  • Raul

    That’s the mistery of human body. Pee has a lot of Nitrogen needed by the plants similar to fertilizers. Old folks in rural areas already know about this long ago.

  • Tim Dunn

    What comes next, the discovery of the wheel?

  • Tim Dunn

    What comes next, the discovery of the wheel?

  • Arun G C

    It may be best alternative

  • Arun G C

    It may be best alternative

  • Sandra Watters

    Responding to Stella Howells’ comment on ‘ days of old’ , people were NOT vegans, we didn’t rise to the top of the food chain by eating only veg.! We are omnivores and if it stood still long enough we would eat it! Farming only came along later and enabled us to settle in one place. Urine has been used for hundreds of years for one purpose or another and we did well on it..waste not want not.

  • Sandra Watters

    Responding to Stella Howells’ comment on ‘ days of old’ , people were NOT vegans, we didn’t rise to the top of the food chain by eating only veg.! We are omnivores and if it stood still long enough we would eat it! Farming only came along later and enabled us to settle in one place. Urine has been used for hundreds of years for one purpose or another and we did well on it..waste not want not.

  • Cindy

    After several years of failing to produce the garden I was used to I decided to try urine. To bad I started at the end of the summer when most of my plants had died but not the peppers. I did it the lazy way I took a dipper and took it right from the Toilet, I then mixed it with a lot more water and started to put it on my peppers, It is almost frost and my peppers are growing like I have not seen in a long time I diluted it even more and used it on my house plants and they are going nuts. I still cant admit to my friends I use urine they will think I am sick but what gardener gives away their secrets anyway…

  • Cindy

    After several years of failing to produce the garden I was used to I decided to try urine. To bad I started at the end of the summer when most of my plants had died but not the peppers. I did it the lazy way I took a dipper and took it right from the Toilet, I then mixed it with a lot more water and started to put it on my peppers, It is almost frost and my peppers are growing like I have not seen in a long time I diluted it even more and used it on my house plants and they are going nuts. I still cant admit to my friends I use urine they will think I am sick but what gardener gives away their secrets anyway…

  • Kevin Arthun

    The issue is not simple; beware. What works for one person could be totally different for another. Urinologists have documented about 3100 different substances that have metabolized in the body and been excreted via the kidneys.

    http://www.urinemetabolome.ca/

  • Kevin Arthun

    The issue is not simple; beware. What works for one person could be totally different for another. Urinologists have documented about 3100 different substances that have metabolized in the body and been excreted via the kidneys.

    http://www.urinemetabolome.ca/

  • Quennbee

    Seriously !!!
    We know what feeding animal remains to animals like the case in mad cow disease does. Don’t you think if we add human pee to our food products, then eat the food we will eventually poison ourselves. Hence all the health problems we already have that aren’t explainable. Stupid idea….

  • Quennbee

    Seriously !!!
    We know what feeding animal remains to animals like the case in mad cow disease does. Don’t you think if we add human pee to our food products, then eat the food we will eventually poison ourselves. Hence all the health problems we already have that aren’t explainable. Stupid idea….

  • Chris

    I am trying to envision the look on my wife’s face when I suggest this. Ah well, anything for the cause…

  • Chris

    I am trying to envision the look on my wife’s face when I suggest this. Ah well, anything for the cause…

  • Donald Morgan

    Urine/Urea has been used in the composting process forever !!!
    Damn fine compost starter and finisher !!!

  • Donald Morgan

    Urine/Urea has been used in the composting process forever !!!
    Damn fine compost starter and finisher !!!

  • Henry Tufuor

    How should urine be collected and used for organic farming? Storage system before application on crops? Method of application of the urine? Quanttity to apply?
    Thanks and Best regards

  • Henry Tufuor

    How should urine be collected and used for organic farming? Storage system before application on crops? Method of application of the urine? Quanttity to apply?
    Thanks and Best regards

  • Henry Tufuor

    Pls how should urine be applied to crops? How it should be applied? method of storage of urine beore application?

  • Henry Tufuor

    Pls how should urine be applied to crops? How it should be applied? method of storage of urine beore application?

  • diane

    Been adding urine to my compost for about 15 yrs, the results of flowers and veggies is amazing. Compost needs to be tossed often and needs an array of different things, leaves, lawn clippings, egg shells, veggie trimmings, I add coffee grinds …

  • Judy D

    I had heard about urine helping your compost pile. But what if you are on medication, have HIV or Hepatitis. She these persons refrain from adding any urine. Would the temps tire of the compost kill any of the diseases?

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