A place where one woman has gathered resources and information to help her family survive in an uncertain future; together with occasional personal musings.

Saturday, April 2, 2011

pee in the garden

Pee in the Garden

Posted by Kate at 9:55 AM
My crusty old uncle Jay told me one of his characteristically amusing yarns once while we were puttering around his garden. He looked kinda like Colonel Sanders, but much leaner, and he spoke with a lovely Louisiana drawl. (He was an uncle by marriage.) His story was about a writer who composed a lengthy poem dedicated to his beloved, who liked to garden. He entitled it, She Sits Among the Lettuces and Peas. His editor liked the theme, but suggested he come up with a more tactful title. The poet considered this advice and then submitted the revised manuscript under a new name, She Sits Among the Cabbages and Leeks. I can hear Jay's gasping sort of laughter now.

Nope. This is not an April Fool's post. I decided that this would be the year we start using pee in the garden in some sort of systematic way. Human urine contains abundant nitrogen, a key nutrient for plants and soil microorganisms. My husband has used the compost pile for the odd leak now and then with my encouragement, but we've never approached the use of urine with any organized intent.

I'd heard of the value of urine in the garden from various sources. After all, garden centers sell urea (which is actually fake urine) as fertilizer, and I know that some compost enthusiasts use pee as a compost activator. Sharon Astyk has written in her inimitable comically informative way about the renewable and cheap nature of human pee. I attended a session on humanure systems at the PASA conference last year, and was sold on the concept even though we don't have access to a good supply of cover material to make it work. I read Carol Deppe's The Resilient Gardener, which further extolled the virtues of urine. And it's not just crackpot greenies talking about this. Heck, even the Washington Post reported on the concept. Researchers at the University of Kuopio's Department of Environmental Sciences in Finland...

...concluded that urine produced by one person over a year would be enough to grow 160 cabbages -- that's 64 kilograms (141 pounds) more cabbage than could be grown in a similar plot fertilized with commercial fertilizer. They recommend collecting urine from eco-type toilets, storing it, then scattering it on the soil around the plants rather than directly on them.

After being bombarded from so many directions, the idea finally worked its way up my priority list. While we may not be able to employ a full humanure system, we can at least divert the less problematic of human wastes into useful channels. Several million pounds of nitrogen are flushed "away" in the US every single day. Homesteading is a process of learning to use what you've got, and learning to find value in what society so often treats as garbage. This is one more resource available to us that we will no longer squander, one more dependency we can rid ourselves of.

Okay, a few technical details. Urine should be diluted 1:7 with water if you keep yourself well hydrated, or 1:10 if you don't typically drink enough water. Too high a concentration of the nitrogen in urine will chemically "burn" plants. Of course, I like to streamline functions around the homestead, since convenience means my good intentions are more likely to result in good practice. So I came up with a simple bucket hack. All that's involved is marking the inside of the bucket to indicate the fill levels that represent the correct proportion of water to pee. There are two ways to go about this, depending on how quickly you anticipate "contributions" being made.

The first approach is to work out the volume of just the first pee of the day per household. Carol Deppe wrote that she uses only her first pee of the morning, since that is typically the most concentrated specimen of the day. I've been doing this off and on for a while now, so I know generally what volume is typical for me. From there one can multiply by 7 or 10 to get the volume of water, measure that quantity of water into a bucket, and mark the surface line with a permanent marker. You may need to empty the bucket and dry the inside very well to mark it. With this method you don't really need a second line indicating the additional volume of urine if your estimate is reasonably accurate. But if you want to put a second mark as a check, go ahead and add your estimated volume of pee to the water and make a second line above the first. Check your accuracy over a few days and adjust as needed.

The other approach is to start with how much liquid you want to carry in the bucket, which should take into account the distance you'll need to carry it, how you will be emptying the bucket (lifting?), and your physical strength. So let's say you're comfortable carrying the bucket half full, or a third full, or whatever. Put your first mark inside the bucket at that level. Then fill to that line using a measuring cup to determine how much liquid it takes to fill to that level. From that measurement, do your calculations - either multiply by 6/7 or 9/10, depending on hydration habits. That will give you the amount of water needed for correct dilution rates. Then empty the bucket and measure in the amount of water indicated from your calculations. Make your second mark at that line inside the bucket, which should be below the first line you marked. When you're ready to start, fill the bucket to the lower line with water, and when enough pee has been collected to reach the top line, it's time to empty the bucket. Rinse, fill, collect, empty, repeat. Free, renewable fertilizer.

There's also the direct method with no need to muck about with dilution or measuring. Over the winter months I've just been adding my morning collection directly to the compost pile. A well established and active compost pile should be able to sort out a concentrated dose of nitrogen and "digest" it, so to speak, before it is applied to the garden. This approach feeds the soil microbes directly, which then later indirectly feed the plants where you apply the compost. If you want to use this method, it's better to not let the collected pee sit around very long, especially at indoor temperatures. The nitrogen in pee is such a valuable commodity that airborne bacteria will colonize the pee almost immediately and begin exploiting it. The faster you get it into a compost pile, the more use it will be to soil microorganisms.

Now for the tedious caveats and common sense warnings, lest I fall foul of the hygiene police and the white knuckled. Human urine is very nearly sterile when it exits the body, unless you happen to be carrying one of a very few nasty diseases. Theoretically, hepatitis B, CMV (cytomegalovirus), and HIV (possibly others) are transmissible via direct contact with urine. There's no data I know of on disease transmission through consuming food from soil fertilized with urine. I regard healthy soil as a universal cleanser of toxins and pathogens of all stripes anyway. Further, it's impossible to infect oneself with any disease. Either you've got it, or you don't. You don't pick something up from yourself. If you're using your own urine in your garden, you have nothing to worry about if you're the only one consuming that food. If you're super cautious, go ahead and test any member of your household for disease who might contribute urine to the cause. Make sure none of you have any disease that could theoretically be passed on to another. As indicated above, apply diluted urine around crops, not directly on them. Finally, you probably want to steer clear of this technique if you sell to the market. The last thing you need is a frivolous lawsuit. To be on the safe side, use it on your fruit trees, berry bushes, corn (maize), ornamentals, or your asparagus crop after this year's harvest is finished.

So what are your thoughts? Is pee in the garden just beyond the pale? Do you already use urine (human or otherwise) as fertilizer? If not, would you consider it?