Composting In Practice

Greetings, Living Earth Gardeners!

Last time we looked at the principles of composting and viewed them as a form of alchemy. This week we will present how we apply these principles in the building of compost piles here at Living Earth Garden Project. These compost piles are built to provide fertility to vegetable beds and orchard trees. We will hold off describing humanure compost piles, once again until next time, as they require extra procedures. (Please review our blog from December 9th, "Principles of Composting".)

The minimum size for a compost pile to properly heat up is 3ft x 3ft x 3ft. Maximum size, with some exceptions, to keep the center aerobic is 6ft x 6ft x 6ft. We build our regular compost piles to this larger size and our first step, then, is to mark out a 6ft x 6ft square on the ground with stakes. Next, using a digging fork, we loosen the soil lying within this square to ensure adequate drainage to the bottom of the pile and thus avoiding anaerobic conditions.

The first materials to be put down are the coarsest, most carbonaceous ones. Here, we use the woody stalks of quelites, a kind of wild spinach that volunteers freely around Taos. Sunflower stalks, cornstalks, or even tree branches could be used instead to ensure that Air is allowed to infiltrate the bottom of a pile. Putting the woodiest materials at the bottom also gives them the best chance for breaking down, and eventually becoming finished compost as well.

The next step is to begin layering green materials (nitrogenous - Fire element) with brown materials (carbonaceous - Rock element). The thinner these materials are layered, the better they will mix together to form finished compost. Yet, layering too thinly makes building compost tedious, so one effective recipe is to fill 2 five gallon buckets with green materials and layer then, then fill 2 five gallon buckets with brown materials and layer that, then back to green materials, and so on. Here in our vega (meadow) land, we are blessed with lush pasture, that, at many times of the year, is at a good ration of carbon (Rock) to nitrogen (Fire) for composting. We simply cut wheelbarrow loads of our pasture and layer them that way, keeping an eye on the proportion of green to brown materials.

It is best to build an entire compost pile all at once, yet in practice, we build onto them as time and energy allow. When we reach a height of 6 feet, we call it done and top the pile off with 4 five gallon buckets of soil. This soil weighs the pile down, holds in moisture, and introduces beneficial microorganisms. Soil could be added with each layer of green and brown materials and doing so would actually introduce these microorganisms more effectively. If following a 2 green/2 brown recipe, add 1/2 five gallon bucket of your own native soil to each layer.

The final step is to drench the compost pile with Water, pouring another 4 five gallon buckets worth on top. Again, it could be more effective to add Water with each layer, fully saturating all the materials up to that level. Sometimes, piles built in this manner, with materials getting completely soaked every step of the way, do not need any supplemental Water once they have been built. Here. in our situation of high winter groundwater, we are beginning with a minimum watering approach, to see how much moisture wicks up from the ground. If a compost pile does not receive enough water, the composting process slows down or stops. and the formation of finished compost is delayed.

Once the compost pile is built, if supplemental water is needed, a good method is to treat the pile as a garden bed. Give water to the pile whenever irrigating the garden beds nearby. Aim for that 50/50 Air to Water ration that we spoke about last time. Such an approach usually produces finished compost within 3 to 6 months, and almost always within one year.

One way to speed up the composting process is to turn the pile. Although some super fast methods call for more frequent turning, I do not recommend turning more frequently than once per month, once per lunar cycle, that is. Turning a pile involves preparing another square on the ground near or adjacent to the first square with woody material also layered on the bottom. Then some kind of strong fork and/or shovel is used to move all the materials over from the first square to the second one. The top and outside of the first pile are intentionally moved to the middle of the second pile, where they will compost better, and the inside of the first pile becomes the top and outside of the second pile.

If a second turning is desired, the compost pile can be moved back onto the first square, and so on, back and forth, with any more subsequent turnings. Although turning a compost pile is optional, and we have not turned our own fruit and veggie piles, one turning can help to ensure a more even breakdown of materials by following the outside to inside, and inside to outside rule.Without turning, some materials in the pile that did not break down fully may need to be screened out or picked out by hand, and then added to the next compost pile that is built, where they will finish decomposing.

Having stated some of the advantages of turning a compost pile, now let's look at simply letting a pile sit. While turning does speed up the composting process by introducing more Air between all the layers of material and a subsequent reheating of the pile to a higher temperature, the primary drawback is that more material, carbon especially, is burned off, oxidized, as the pile reheats each time, so that there is less finished compost as a result. A compost pile left unturned may retain as much as one-half of it's original built volume when finished. On the other hand, a frequently turned pile may give us little as one-tenth of its' original volume. To use a cooking analogy, this would be the difference between letting one pot of soup simmer, after an initial boil, and keeping a second soup on high hear, or continually bringing it back to a boil. The second soup will boil down much more quickly and yield less food overall. Water could be added, but the flavors (nutrients) will not meld together as in the first soup. Once again, we find that having patience is indeed a virtue!

Having now presented Composting in practice, next time we will look at the extra steps and precautions that need to be taken when composting humanure.

As before, we welcome your questions and comments.

With best wishes for these Winter Holidays.
Gardener Machei
Taos, New Mexico

Principles of Composting - Living Earth Garden Project Blog VII

Greetings, Living Earth Gardeners! Last week we looked at Sawdust Buckets and completed our survey of Composting Toilet Systems. Thank you for your questions, comments and shares! We have now addressed the first 2 of our 4 Secondary Design Elements/Support Systems of our project. Let's review the list:

• Well - for access to clean drinking water
• Compost Toilets - to capture nutrients and avoid waste
• Solar Shower - to rinse off sweat and dust
• Compost Piles - for maintaining soil fertility

Although we have looked with some thoroughness at Composting Toilets, we have really only addressed the first half of this process: the capturing of nutrients and the avoiding of waste. The second half is about transforming this would-be waste into a beneficial product that can increase soil fertility. This process is composting, and we will skip down to the 4th element of our Secondary Design/Support Systems list : Compost Piles.

Let's begin with regular fruit and vegetable composting, and hold off on humanure composting until we have some basics down. Composting is ultimately a process that involves Alchemy. There are many methods and recipes out there, some of which you may already be familiar with. At the highest level, success with any of these methods is a result of keeping in balance the 4 traditional elements:

• Fire
• Air
• Water
• Earth/Rock

The 4th element, although commonly referred to as Earth, I prefer to think of as Rock. This is to keep in mind that we are not speaking about the entire Planet Earth in this case, just the densest, coarsest, most solid material found on her surface: Rock. Weathered rock is the parent material for all soils, but to form good fertile soil, the elements of Water and Air are needed and Fire to spark biological activity. Let's see how each Earth Element is represented in the compost pile:

Rock - the densest material is represented by brown, fully matured carbonaceous plant matter. Usually, when composting, it is found in the form of straw, but anything that has hardened and is biodegradable can potentially be used: fallen leaves, twigs and branches, wood shavings, animal bones. Carbon materials give a compost pile its' substance.

Fire - the element of lowest density, is represented by green, supple plants containing high percentages of nitrogen. Nitrogen is what sparks biological life and plant growth in our gardens. Nitrogen sparks microbe activity in the compost pile. Although represented by lush vegetative growth, any plant matter that has been cut while green, even if allowed to dry, can be used as a fire element: hay, grass, clippings, tomato and potato vines, green leaves. Similarly, animal manures are also high in nitrogen and both fresh and dry manure can be added to compost piles.

Water - is represented by the water we deliberately add to our compost pile, by rain we allow to fall onto a pile, as well as by the moisture contained in the plant and animal materials that we build our piles with. Too much water creates an anaerobic condition. In general, soggy anaerobic conditions can produce harmful bacteria and should be avoided. Not enough moisture and the composting process stops, too much Air.

Air - is represented by the open spaces within a compost pile. Certain materials, such as branches, are very effective at keeping air pockets within a pile, while other materials, such as grass clippings, tend to mat down and resist air infiltration. In general, it is more important to ensure that Air has access to the bottom and center of the pile. than it is to the top and sides of one.

Keeping a proper Air to Water ratio is one important key to composting success. Good, loose, friable garden soil can be used as an example. This good garden soil contains ~50% pore space. Ideally, this pore space is half-filled  with water and half left open to air. Of course, in practice, the water content in both soils and compost piles, is constantly fluctuating between one extreme and the other. Our job as Gardeners is to keep this 50/50 Air to Water ratio as best as we can (with some adjustments, in certain situations). Compost piles should be managed with the same goal in mind: keep that 50/50 balance as best as we can, over time.

The other balance to keep in mind when composting is that of Rock and Fire, that represented by carbon and nitrogen. In general, if carbonaceous materials and nitrogenous materials, as defined above, are added in equal parts, by volume, again a 50/50 ratio, by volume, this will keep an effective Carbon to Nitrogen in balance in the pile. This 50/50 ratio of Rock to Fire is more difficult to achieve than that of Air to Water because there is much more variability in these carbon and nitrogen materials. However, the truth is, that as long as the Air to Water ratio is kept fairly well-balanced, the microbial life in the pile will transform almost any combination of carbon to nitrogen materials into finished usable compost within one year's time in most locations. So, please do not be hesitant to start composting by what may seem to be, at first, an overly complex process. The microbial life within the compost pile will find the food combinations that they need. The only question is one of efficiency, and that we can improve through practice. Speaking of  microbial life brings us to a final analogy.

The compost pile can be seen as one large stomach, a giant digester. When we build a pile, we are feeding the microbial life in that pile, the 'bioherd'. This microbial life prefers a balanced diet, just as our own bodies do. Nitrogenous materials (Fire) are analogous to us living on a diet of fruit and salad vegetables. Fruit, especially, gives us quick energy to get going, but does not sustain our activities over time. Carbonaceous materials (Rock) are analogous to a diet of grains and root vegetables. Grains give us energy for the long haul, but without some Fire accompanying our meal, these foods can leave us feeling too heavy to get started. Likely, I believe , that we have all gotten by on an imbalanced diet for a time, until learning better habits from the experience. Both kinds of energy, fast and slow, are necessary for our bodies and for the body of the compost pile.

Well, there I go again, using up all our time and space, and just getting through the basic principles of composting. Let us know if there is too much detail , or not enough! Next week, we will continue by describing how we actually apply the principles presented today to the building of compost piles here at Living Earth Garden Project.

With best wishes for this week,

Gardener Machei

Taos, New Mexico

Sawdust Bucket Composting

Greetings, Living Earth Gardeners! Last week we looked at Composting Toilet Systems in general. We noted that the composting of our own bodily wastes is an uncomfortable subject for many people, and this was acknowledged during the week. We revealed that there have been many different humanure composting systems developed that range widely in terms of complexity, cost, and user-involvement. We finished by considering that it is fairly safe and simple to begin with composting our own urine, even in a town situation. The book, Liquid Gold, bu Carol Steinfeld, shows various other ways in which to capture urine and then recycle its' nutrients for the benefit of plant growth.

Before moving on, allow me to note that although composting toilet systems are currently optional and voluntary, they are likely to become required of all of us in the future. Every time we flush a toilet, we are not only wasting good water, but we are also sending soil nutrients and organic matter out into our waterways, eventually, in most cases, to be deposited into our oceans. Those nutrients and organic matter need to go back into the soils that they were removed from. Current estimates, including those from the United Nations, predict that at present rates of soil depletion, we humans will have no farmable topsoil left on Earth in 30 to 60 years time.

Okay, having said that, let's move into the particular method of human manure composting that we have chosen to use here, at least for now. This method is known as the sawdust bucket system and is described in detail by Joseph Jenkins in his book, The Humanure Handbook: a guide to composting human manure. When starting on a land-based project, knowing what to do with our own bodily wastes can be an immediate barrier. In Wilderness Areas, we are directed to dig "cat holes", 6 or more inches down, and then cover our deposits thoroughly to keep wild animals from digging them back up (in their search for nutrients). Unless one has a very large tract of land, and is willing to walk to a different place each time these "cat holes" would soon accumulate beyond the ability of our land to absorb them.

The traditional toilet method on the homestead is the outhouse, or 'privy'. This is actually what I had in mind before we obtained our particular piece of land. I thought that we would simply dig a hole in the ground and put a toilet and outhouse on it. Then, when the hole was full, we would plant a tree over all those deposits to recapture the nutrients stored there, and move on to a new hole in a new spot. Our land is blessed with an abundance of groundwater. This groundwater makes possible plant growth that would otherwise be impossible in our high desert climate. High groundwater does make building more complicated, however, and one of those complications was that we had to dismiss this "outhouse/tree system" idea.

Although it did seem like a complication at the time, Joseph Jenkins shows through drawings that the old outhouse system was never all that good of an idea anyways. Unless the hole is lined and then pumped out, the pathogens in feces do leach into the surrounding soil, contaminating it both vertically and horizontally. This contamination happens in dry soil too, just not as broadly as in wet soil. The good news was that I had already been composting for 15 years, was familiar with a few different humanure systems from the farms I had worked on, and had recently taken part in a demonstration of this sawdust bucket system. I went ahead and read The Humanure Handbook thoroughly.

The sawdust bucket method is a simple system. First, we purchased a 'portable loo' by mail from a camping outfitter. They are made in Canada, but all it is essentially is a five-gallon bucket with a plastic seat and lid that snaps securely to the top rim. We then purchased some more five-gallon buckets with regular lids from the hardware store and gathered a large tubful of fresh sawdust from the local sawmill (to cover with one cupful each humanure deposit, whether solid or liquid, as well as giving each bucket and cupfuls at the bottom to start). We set up a small table and kept it supplied with toilet paper and alcohol-based hand sanitizer (which does not freeze in the cold weather). Later, we purchased another plastic toilet seat with lid in order to separate urine from feces (it is when the two are mixed together that the most disagreeable odors are created). By separating, the sawdust was able to absorb not only all of the liquid involved, but just about all of the odor as well.

As far as the 'privy/privacy' part of this composting outhouse system, we first put up a potty tent that was available through that camping outfitter, and as sunlight and wind degraded the nylon, we built strawbale walls on cement blocks around it with a wooden bond beam on top to keep the bales upright. A simple canvas tarp served as roof until it began breaking apart, at which point we replaced it with wooden slats. The doorway was left semi-open as it faced away from most activities and out onto 50 miles of open plateau with buttes and mountains on the horizon. All of this makes walking out to our 'composting potty' to make a 'time deposit' (with interest guaranteed)., a beautiful and unforgettable experience!

That is all anyone essentially needs to get started. While our approach reflects the realities of our land and climate, the underlying principles will remain the same anywhere. The outhouse structure, in particular, that we built around the toilets is well-suited for our high desert climate of  low rainfall, strong winds and extreme temperature swings. This kind of structure may be inappropriate, or need modification, in other bioregions.

Now, what to do with all the stuff in the buckets? Well, that is where some level of skill and knowledge are required. We will begin on that next week, when I will address Composting, both with humanure and with regular garden debris. As usual, please send us your questions.

With best wishes for this week!
Gardener Machei
Taos, New Mexico