Should I pee on my garden?

So you've heard somewhere that urine is good for your garden, but should you really pee right on your garden? The short answer is yes, you can, but there are certainly better options. Here are the what's and why's for what you should do instead.

Why is Urine Good for Your Garden?

Plants need three things in large quantities in order to grow - they are Nitrogen, Phosphorus, and Potassium, or NPK for short. Nitrogen makes your leaves lush and green. Potassium enriches the flowers and fruits. Phosphorus builds strong roots! Plants need other things too, like Carbon Dioxide and other trace minerals, but unless you live in an area where there is a scarcity of these, you likely have enough of them already in your soil. NPK is different, in general, the more NPK you have for your plants to eat, the more your plants are going to grow.  Urine contains all three of these elements in fairly large quantities that are easily absorbed by plants' roots. Nitrogen makes up a large percentage of what is in urine (12%). Potassium is also in there at a sizeable amount (2$-5%). Phosphorus is the least of the three (1% to 2%), but that is actually a good thing, as too much phosphorous can make the soil acidic and burn your plants. So, as you can see, once you get passed the gross out factor, urine has the essential nutrients that plants need to grow. In other words, your pee has got what plants crave! Crazy how so many things in nature work that way.

Solution for the Lazy, Go Right Ahead and Pee on Your Garden!

If you don't have the time or resources to compost your urine (it's actually really easy), peeing on your garden is just fine. Just make sure that you pee on the soil and not directly on the plants because the urine left on the leaves, if done frequently, could potentially burn them. It's the roots that are going to soak up your nutrients anyway and the soil will retain the nutrients and lose less of them to evaporation. While this is an okay method, it's not the best option precisely because peeing right on top of the soil will allow much more of the nutrients in the urine - especially the nitrogen - to evaporate right back out into the air. Evaporation will occur at a higher rate when it is warm and windy and less when it's cold and rainy. For the slightly less lazy, you can cover up the urine with a layer of soil and most of the Nitrogen stay in the soil and pass directly to the plants within a few weeks.

The Best Method - Incorporate Urine into Your Compost

If you already have compost pile or are looking into getting one, then consider incorporating urine into your compost. Yes, you can pee right into your compost without any problems for the compost. If you do pee on your compost though, just be sure that you don't do it in a way that people can actually see you - on account of public indecency laws. Composts should be covered or enclosed in general, so that all of those awesome plant nutrients don't evaporate into the atmosphere before they get to your plants. The combination of covering along with the urine will help everything in your compost break down much faster. If you do not cover your compost (seriously, you should), then make sure to mix the compost slightly or add more compostable material after leaving your liquid deposit. As described in section 2, this will ensure that most of the Nitrogen does not leach into the air.

As an Aside, Doing Number 2 in your Compost

The, ahem, natural follow up question to doing Number 1 in you garden is should you do Number 2? Humanure, or night soil, is compost made from human feces. Yes, it really is a thing, in fact, I saw many sustainability volunteers establishing their own methods while I was in the Peace Corps. Again, once you get passed the gross out factor, everything breaks down into molecular building blocks and these building blocks are recycled all over our planet to produce new life. According to the EPA, humanure, or biosolids, are being used in all 50 states to grow crops. While humanure is being utilized at the mass production level in the US, it may be illegal to utilize this composting method for crops at the personal level. Check your state and municipal laws for more details. Humanure needs to be composted for two full years after the last material deposit. By then, it is likely to be devoid of harmful human pathogens, but it will have also lost much of its nutrients to its surrounding environment. Even still, I would not personally risk using it for root vegetables. If you are interested in this process, I recommend starting with the Wikipedia section on humanure and then following up with the books linked to the article. Before you go to such extremes, understand that your excrement is likely already being processed for industrial crop production through your local municipal water treatment plant. Rather than humanure, you are likely to get better composting results at the personal level from composting urine and incorporating vermicompost into your processes.

Urine, however, is completely safe (barring any rare urinary infections) and can be used on plants throughout the entire cultivation process. It has the essentials that plants need to grow. So, should you pee on your garden? Yes! Your plants will be happier because of it!