There are lots of organic fertilizers out there: Fish emulsions, corn gluten meal, guano. Many of these fertilizers (all that I listed above with the exception of the guano) are by-products of some other industry. Still, they need to be shipped from somewhere to somewhere to get to our garden and so they cost energy — and of course they cost us money. But there is a high nitrogen fertilizer that you can use which doesn’t come from a long way away, and that’s pee. Holly mentioned using pee to help compost piles of stray a few months ago (you can find the news story on the right side of this blog), and I, for one, think it’s a great idea. But really, pee can be used as a fertilizer without the compost.
Yesterday I was working on a project and decided to goof off a little by figuring out how much nitrogen was actually in urine. Here’s the conclusion — Urine contains about 4,000 pats per million nitrogen. In terms of what plants can handle, that’s a lot (which is why dogs produce “dog spots” when they pee on a small area of ground — too much nitrogen in a small area). 400 parts per million nitrogen, applied once a week in irrigation water, is what you might apply to encourage the growth of greenhouse plants. Urine, by the way, is also relatively sterile (unless you’re dealing with a bladder infection) and so using urine is relatively safe as long as it’s used quickly. It also conserves water because you don’t need to flush. So, the way I figure it, you could mix 1 part urine with 9 parts water and have a really good once a week (or two weeks) fertilizer application for your flowers (I don’t know if I could bring myself to fertilize cabbage, broccoli, or tomatoes with it…). You’d be saving yourself the cost of fertilizer, saving the environmental cost of shipping the fertilizer you might otherwise purchase, saving water, and you’d have something unique to tell your gardening friends about. Win – win situation as far as I’m concerned.
20 thoughts on “Want an organic source of nitrogen that isn’t shipped from halfway across the world? Urine luck”
I feel a patent in-the-works for a fertilizer injector adapter for home irrigation systems.
PS – Jeff, I always knew that you were quite the wiz!
Ok. All joking aside. How would this convert to a fertilizer ratio for say a gallon of urine?
Daniel — All you’d need to do is mix that gallon of urine with nine gallons of water. However — your bladder probably doesn’t hold a gallon of urine (I’m just guessing of course), so you’d need to save your urine up to get a gallon. This isn’t a particularly good idea because, though urine is relatively sterile when it exits the body, it quickly picks up bacteria which aren’t necessarily good. fresh is best.
Earlier today I posted on FB about how one of my nephew’s relieved himself on some Ipomoea seedlings that weren’t doing much and started to grow.
Even though they do ok in poor soils, there wasn’t enough nitrogen in the soil to help them along.
Jeff, there are scientists who don’t share your reservations with regard to fertilising cabbage …
A 2007 study in Finland showed that human urine could be used as a fertilizer for cabbage and does not pose any significant hygienic threats. http://pubs.acs.org/doi/abs/10.1021/jf0717891
So urine as fertiliser apparently doesn’t leave any distinctive flavor in food products but still … somehow sheds a new light on the term “sauerkraut” for me …
Good stats for fertilizers. Enjoyed reading it. Thanks for posting.
I like it! Now I just have to figure out an efficient way to get it on the garden without exposing myself to the neighbors… I think I need a taller fence.
Whenever we have a drought, I can get my husband to pee on the compost pile. We live in the country, so no neighbors and it conserves our well water.
Awesome! I’ve always wondered about this. What about salt build up? Are there any other funky things in pee that could be problematic if allowed to concentrate over time and if so, would leaching do the trick?
This is SUCH a guy thing!
So, from now on I’m supposed to have watering cans next to the toilet?
This is no surprise to me. For years I’ve been using water from my fish tank on my plants. One reason to “change” the water in a fish tank is to reduce nitrogen levels. Not nearly as difficult as getting The Husband to pee on the front yard garden!
Fabulous stuff, Jeff. Have you ever come across any evidence of varmint repellent properties? I keep sending Joel out to the bean patch every evening…(I can say with confidence it has zero effect on flea beetles and Colorado potato beetles)
“Don’t poop or pee where you eat” is one of those extremely important public health issues we’re still trying to convince people in 3rd world countries the importance of. We don’t have pathogens of this sort because we handle our wastes pretty well. If we stopped, say hello to cholera and friends once again.
Aside from that, urine is NOT sterile or pretty sterile: http://www.smithsonianmag.com/ist/?next=/smart-news/turns-out-urine-isnt-actually-sterile-180954809/
I can see using urine in a hot compost if you are assured of no runoff. But using your pee elsewhere is like skipping vaccination. Can YOU get away with it? Yeah, probably, but only because everyone else isn’t trying it, too. Very bad idea.
I’ve noticed I’ve been the voice of doom here. To be happier: A composting toilet, though, is a really GREAT idea, and the survival of pathogens extremely unlikely! Please feel free to use composting toilet compost on your yard and veg. 🙂
Not far-fetched at all… have been ruminating on our absenting ourselves from ecology and nutrient cycles. We are the dominant “mega fauna”, and a huge part of our role would have been our “waste products” added to the soil. But we hide those away in places hard for plants to reach. If you think about the important role buffalo played in the ecology of the plains, it was seed dispersal and spreading of fecal nutrients over large areas. I would like to find a non-“icky” way to have these nutrients nourish my property. I worry about medications I take, but believe that a nothing-in-nothing out form of gardening is the goal for me. No leaves or yard waste leave either, but are allowed to decompose naturally…this creates habitat for numerous creatures.
This is an old blog post from 2010 and very outdated. Jeff isn’t wrong that it is a source of N and he does explain you have to dilute it or it will cause problems. It was commonly thought to be sterile back in that day but now, of course, that has been debunked, urine is not sterile, bacteria love it and it can be a disease vector, it is easy to burn stuff with it and it is illegal in a lot of places.
Thanks for your comment, Bec Wolfe-Thomas. I’m also concerned about the amount of salt in human urine.
urine is really good fertilizer don’t listen to the people that think it spreads diseases, every time a toilet is flushed fecal matter sprays everywhere.
Also a lot of people don’t wash their hands and contaminate ice used in drinks, and then there are pet turds all over the place with flies landing on them spreading disease.
People must be immune to most of this or more people would be getting sick.