It is known that urine has many positive effects on plants due to its chemical composition (Nitrogen, Phosphorus, Potassium).

However, it is now also known that even organic food consumers end up with detectable amounts of glyphosate in their urine (with an order of magnitude of a few nanograms per millilitre).

To which extent does it make urine now unsuitable in a vegetable garden?

  • Arnaud...is it possible that you could find that source showing that glyphosate is in our Urine? But as an aside, can you IMAGINE people drinking urine? They say blatantly that Urine is sterile. HELLO??
    – stormy
    Aug 30, 2019 at 22:42
  • This from 2017...probably more recent ones available upi.com/Health_News/2017/10/25/…
    – Bamboo
    Aug 31, 2019 at 10:05

1 Answer 1


Well that is the 64 dollar question... It is likely that the amount of glyphosate present in human urine is at such a low level it will be ineffective as a weedkiller, but nonetheless, glyphosate binds tightly to soil particles and will persist for six months. There is a case study that shows glyphosate treated ground produced carrots two years later with glyphosate residue with them, so it may in fact persist for longer in some soils. The formulation of the product used (assuming its not basic, unadulterated glyphosate on its own, diluted appropriately) also makes a difference; the additional ingredients used in various brands may increase the potential for longer persistence.

Usually, though, it is recommended to add urine to a compost heap rather than using it fresh on cultivated areas; given the length of time for the compost to break down to a useable material, the risk of glyphosate contamination from that will likely be very low indeed. If you want to use your own urine as a direct fertilizer, switch to eating organic breads, cereals, flours and oils to avoid the larger doses of glyphosate commonly applied by growers as a dessicant on grain crops immediately prior to harvesting, and choose organic produce (including meat) wherever possible; whilst organic producers do still use chemicals, glyphosate is not among them, which means your own urine will contain much less (or none, if you only ever eat certified organic produce) assuming you're not using glyphosate yourself.

  • "If you want to use your own urine as a direct fertilizer, …." in the north-east of England, the traditional method of growing prize-winning large vegetables is to fertilize them with Newcastle Brown Ale - though it needs to pass through the gardener to filter out the alcohol before applying it to the plants :)
    – alephzero
    Aug 28, 2019 at 18:49
  • Urine is not a BALANCED fertilizer. I love the 'brown ale' Alephzero! I am so disgusted with Urine and its smell I gag just thinking about people actually DRINKING this piss. Glyphosate changes chemistry the second it connects with whatever it is sprayed upong. Glyphosate has gotten a very bad rap because people do not understand chemistry, pesticides, fertilizer nor soils.
    – stormy
    Aug 28, 2019 at 21:46
  • @alephzero - I'm in the UK, and I believe what you said!
    – Bamboo
    Aug 29, 2019 at 0:20
  • @stormy - the OP does not claim urine is a balanced fertilizer, he merely says it has 'positive effects' , which it does for its nitrogen content alone, especially in compost heaps...
    – Bamboo
    Aug 29, 2019 at 0:23
  • Great in compost piles to feed the decomposers. My goodness, Bamboo.
    – stormy
    Aug 29, 2019 at 7:25

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