Better Tomatoes... with Urine?

[pilotguide]

Interesting study finds plants love this stuff. I wonder how long before some endeavouring mad scientist tries this out in a hydroponics system.

Better Tomatoes Via a Fertilizer of...Human Urine? | Popular Science

[chinamon]

human urine might have nitrogen, potassium and phosphate but im pretty sure there are also a lot of impurities that we wouldnt want in our food. it is human WASTE afterall. i will stick with a good fertilizer.

[pilotguide]

In the article they had said they let it settle for 6 months and tested it for bacteria etc. There would definitely be tests in place to ensure it was safe... or at least we hope. :-)

[GpsFrontier]

It is well known that "Waste" animal or human is beneficial to plants. Cow, chicken and fish manure are probably the most common. Even "Black Gold" also known as compost is in some cases largely worm manure. Though urine would normally have too much ammonia in it that would be toxic to some plants, especially in large amounts. But I would assume that the 6 month waiting period would give the ammonia enough time to break down so that it is not toxic to the plants anymore.

I don't see a problem using this for soil grown plants, but I do see a big problem with Hydroponic plants. Nitrogen, potassium and phosphate would not be desirable to add to a hydroponic solution. When using Hydroponic nutrients these elements are already present in the popper proportions, adding them to a well balanced solution only will through off the balance of those elements.

Elements needed for Hydroponic plants

[Luches]

Interesting...
Actually, any urine that comes directly from a urinal tract of a healthy human (perhaps many other mammals) is STERILE!
Only later, when bacteria infiltrate (literally) and start to decompose ammonia, some protein residues and whatever, (dunno the exact composition of human urine) this kind of liquid gets "infected"... and hence starts to decompose and smell real bad, as we know.

In first aid, it's well known that urinating directly over a wound or burning is the best thing you can do (in case of emergency and without classical means) to clean and sterilize a wound! In some cultures, drinking fresh morning urine, is a kinda wired (for some extremely disgusting) but quite well known and commonly accepted custom (actually cure or therapy)!

To really know if it is wether useful, beneficial or rather inadequate or even inappropriate as an ADDITIVE in a nutrient solution, one should A. investigate it's exact composition in terms of NPK, other macro- and micro-nutrients. And B. inquire about it's behavior in a solution in different quantities - a shot of it (which will perhaps not lead to any smell or other negative influence) might have a very different effect as a large quantity. Surely the ammonia part will not decompose properly, but in many recipes, there is a certain part of ammoniacal nitrogen anyway. The quantity will also determinate if it may interfere with the balance of the nutrient composition. Btw: A nutrient is never 100% balanced - as it's composition anyway changes permanently due to irregular absorption of different elements ( as in during the 10 days it remains in the reservoir).

[ObbieDoobie]

Yeah, I did a summer long test in my hydroponics system. Growing lettuce, basil and others.

I had started using urine as a fertilizer in the water supply.
I found that the lettuce grew exceptionally well. After a late spring disaster while I was out of town, I had to restart my hydroponics system (the bucket was empty). I stopped using human urine in the system and some of the plants are still living. I planted a whole new sweet of lettuce, corn, basil. And after giving them a good start... they all looked yellow and undernourished.

After 3 months with very little growth, I began to pee in the water supply and saw instantaneous rebounds in all the plants. Now the heads of lettuce are large enough to eat, after about 50 days.

No artifical lighting was used in the grow of these plants.