There was a rumor going around a couple of years ago that you could pee on a straw bale and it would turn into compost. The theory was nitrogen (in pee) plus carbon (in straw) equals compost. I liked the idea that pee could be useful, so I buried a straw bale in my yard to test it out, and wrote about it here.
18 months and many gallons of pee later, I dug it up–an incredibly stinky affair, but hey: science. The short story is that it didn’t work. At all. If anything I’d guess that whatever is in pee besides water has a preservative effect on the straw. There were a couple bugs and grubs, but really just a couple. There was no visible sign of any decay. My guess is that if I’d dumped water on that bale in the same quantity as the pee, it would have at least grown some mildew and broken down a little.
At this point, I have to assume the best place for pee is in the septic tank, as much as that pains my permaculture heart. I would love to be proven wrong about this, but don’t just tell me about a theory. Show me evidence.
Here’s mine. These images are of all the “decay” I could find after going through the entire stinky bale:
The bale, still buried. The level of the straw dropped about a foot over the course of 18 months and I topped it off, hoping that the drop meant decomposition, but it turned out it just compacted.
I found some kind of bug early on but never saw another of this kind.
And here are the 3 grubs I found.
Mostly it looked like this: Pee-soaked, compressed straw.
There was some discoloration like this.
Sal bug in a rare dry spot.
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February 17, 2015 at 12:04 pm
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February 17, 2015 at 4:59 pm
I’m not sure your visual test is the whole story. Urine is certainly full of urea, and thus nitrogen, and it’s been used that way lots of places. But what you are describing sounds like you’re nitrogen-burning the haybale–probably kicking its salinity up way too high for most microorganisms to deal with it. The practices I’ve heard of usually involve diluting urine at least 10:1 and then using it for irrigation or as a foliar spray.
February 17, 2015 at 7:36 pm
I’m not sure it’s the whole story, either. I hope it’s not–just trying to scare up some counter-evidence. I tried the irrigation method, too, and wrote about it in my earlier post. I diluted it at least 20:1 and it killed the greens I watered with it.
February 18, 2015 at 1:50 pm
I bet that the aridity (and salinity?) of your location is a big factor. Urine fertilizers are traditional in places like coastal China, but they’re getting orders of magnitude more rain than you are. So their 20:1 ratio might wind up being more like 50:1 once it’s in the ground. Whereas it sounds like your plants basically don’t encounter any water molecules that you don’t hand-deliver to them.
February 18, 2015 at 7:51 pm
Could be. It’s definitely true that our plants only get the water we give them. It rains maybe 4-5 times a year. Reanna’s on the road right now and called me from Arizona and she was like, “You call this a desert? Everything is covered in dew in the morning!” We don’t have dew in Joshua Tree.
March 2, 2015 at 9:50 pm
If the straw was thoroughly saturated then would oxygen availability be an issue? Traditional composters are all about how anaerobic is not good for compost. Grass also doesn’t compost well unless you have a well balanced, well mixed pile. If we dump in a lawn’s worth of grass clippings and don’t mix well we get an un-composted layer of grass in the pile and that is where there is lots of rain and thousands of earthworms. I keep thinking of controls to run but they would have been a lot of work and possibly inconclusive.
March 12, 2017 at 10:54 pm
Having done this successfully, here’s what went wrong in my opinion. Sounds like burying the bale prevented it from draining properly and your bale was anaerobic. I set my bail on gravel, above ground, and I’ve never had this problem. Additionally, it sounds like you put way to much urine on it. Maybe a quart or two of urine diluted in a five gallon bucket (some urine is darker and more concentrated), with a scoop of manure for some bacteria, stirred up and poured on one bale is all that you need. Sometimes less is more, it’s all about the ratios!
March 12, 2017 at 10:57 pm
Also, full composting should happen in a matter of weeks, not 18 months. You can compost an entire deer in less than 18 months.
February 9, 2018 at 1:54 pm
Tried straw bale gardening without the artificial fertilizers; pee on one bale, commercial plant based organic fertilizer on another and bokashi’d food scraps on the last. Bales sat on the surface of the ground. The commercial fertilizer had a hard time incorporating into the bale with poor resultant plant growth. Bokashi’d scraps not much better (I would blend the bokashi cake with the bokashi tea and water next time). The urine was great. The bale started to smell after a few quarts application so I poured worm tea over it which eliminated the odors in 24 hours. Bale heated to over 100 degrees Fahrenheit (about 40-50 degrees over ambient) and was planted in the spring with collards and sunflowers. Growth was as good as garden bed and 70% of bale had completely broken down by fall (all on the inside and bottom of bale). Nice consistency and full of worms.