Making Compost With What You Got

Composting artificially accelerates the decomposition of crude organic matter and its recombination into humus. What in nature might take years we can make happen in weeks or months. But compost that seems ready to work into soil may not have quite yet become humus. Though brown and crumbly and good-smelling and well decomposed, it may only have partially rotted. – Steve Solomon from Organic Gardener’s Composting

My Mother’s expression, “life is best left as a mystery”, is the way I’m tempted to feel about composting. It’s the type of thing I want someone to give me a recipe for and just like that I have rich, sweet smelling compost that will make my beans ready for Jack to climb to the sky on. There are countless articles, books and videos on the subject and countless methods and contraptions marketed for making it. I won’t act like I fully understand it, nor will I go into the details about how it’s made. All I do know is it’s all good, but like dirt, some composts are much better than others and making it right is no easy task. Steve Solomon compares making it to making beer as it involves fermentation and careful attention to ingredients, temperature, mixing as well as many other factors.

With so much overwhelming and many times conflicting information about it, I can only say to the first time composter that unlike fertilizer (which can turn into a disaster if it’s not made right) making compost is almost always good for the environment and the garden. Another way I like to think of it is, it’s basically the poop of many tiny animals all around us and this poop is something that actually smells good and makes things grow. What a beautiful concept.

So how is it made? Not sure I want to go there but what the heck. Plainly speaking, there are all these tiny animals all around us we can’t see whose mission in life is to break things down into something I mentioned earlier, called humus. As I’ve said, anything will break down, but some things break down in a few months especially if they are mixed with the right ingredients and under the right conditions. Generally those conditions require heat, air, moisture and the perfect blend of “browns” (or carbon sources) and “greens” (nitrogen sources). “Greens” are generally fresh organic material like grass and leaves (that are still green). “Browns” are older and dryer organic materials such as straw and dried leaves (that have turned brown). A good source for examples is here . I have lots of the “greens” but not so much of the “browns”. Actually, I take that back. I have lots of “browns” like paper and cardboard but “browns” with too much carbon break down very slowly. For example, sawdust has an extremely high carbon to nitrogen ratio (or C/N ratio). The higher that ratio is, the longer it will take to turn into compost which poses a problem if you’re trying to speed up the decomposing process. So I’ve come to the conclusion that for my small composting operations, I may want to stay away from using material, such as cardboard and paper with a C/N ratio that will take longer than my particular situation requires. Anyway, from what I’m gathering, unless you’re Vermicomposting (or composting with worms) it’s best to have a C/N ratio of around 25:1.

So you have your kitchen scraps like egg shells, coffee grounds, lettuce and apple cores, etc. You throw them in something like for me, a bowl. When it fills up you add it to the compost pile. If you do nothing but continue to add your kitchen scraps, you can come back in a year, turn your pile and find some nice worms and sweet smelling, crumbly stuff at the bottom. This method is called Cool or Passive composting because the pile doesn’t heat up. It works but takes about a year and can be faster if the pile is turned twice a year.

A quicker method that generally produces better results is Hot or Active composting. This method requires the pile to sit for a period of time without the addition of new materials. When the right combinations of air, heat, water, “greens” and “browns” are mixed together, it triggers bacteria to reproduce and rapidly feed on the pile causing the temperature to raise to around 130 – 170 degrees F. Once these bacteria finish eating, the pile will cool down and enter a new phase of decomposition. This link explains the process.

How in the world do you adjust for that perfect “green” and “brown” ratio? Math wizard I am, I must confess I do nothing of the sort. Steve Solomon has a more practical alternative.

It is far more sensible to learn from experience. Gauge the proportions of materials going into a heap by the result. If the pile gets really hot and stays that way for a few weeks before gradually cooling down then the C/N was more or less right. If, after several turnings and reheatings, the material has not thoroughly decomposed, then the initial C/N was probably too high. The words “thoroughly decomposed” mean here that there are no recognizable traces of the original materials in the heap and the compost is dark brown to black, crumbly, sweet smelling and most importantly, when worked into soil it provokes a marked growth response, similar to fertilizer. If the pile did not initially heat very much or the heating stage was very brief, then the pile probably lacked nitrogen. The solution for a nitrogen-deficient pile is to turn it, simultaneously blending in more nutrient-rich materials and probably a bit of water too. After a few piles have been made novice composters will begin to get the same feel for their materials as bakers have for their flour, shortening, and yeast.It is also possible to err on the opposite end of the scale and make a pile with too much nitrogen. This heap will heat very rapidly, become as hot as the microbial population can tolerate, lose moisture very quickly, and probably smell of ammonia, indicating that valuable fixed nitrogen is escaping into the atmosphere. When proteins decompose their nitrogen content is normally released as ammonia gas. Most people have smelled small piles of spring grass clippings doing this very thing. Ammonia is always created when proteins decompose in any heap at any C/N. But a properly made compost pile does not permit this valuable nitrogen source to escape. – Seve Solomon from Organic Gardener’s Composting

As you’ve probably already discovered there are countless contraptions marketed to the gardener for composting. Here are just a few.  As much as I would love to make an open air pile of compost, unless I want to thoroughly irritate my neighbors or invite unwanted critters, I’ve decided against it. Gracious family members have endowed me with two bin composters known as “tumblers”. The idea behind them is the contents can get air while the drum is being turned therefore speeding up the process. The compost is also contained from critters. Tumbler bins aren’t cheap (no less than $100.00) and up until now I haven’t had the best success which I can attribute to ignorance and neglegence but it’s high time I turned over a new “leaf”. This is serious.

Seriously, tumbler bins work by Hot composting. It’s a little tricky to get everything right as there is only a small opening in which to get at the contents but I’m going to give it my best shot. The University of Maryland Extension explained it to me this way:

Your ‘urban’ setting does provide you with some composting challenges. Elevated tumblers are a good idea to prevent rodents. On the one hand, tumblers are designed for ‘hot’ composting, i.e., filling the bin with the proper mix of materials and not adding additional materials until the finished compost is harvested. What you may try is keeping a ready supply of shredded dry leaves, sawdust, or straw next to your tumblers. Use one of the tumblers for your daily addition of kitchen scraps and add an equal amount of the dry carbonaceous material. Check the moisture content and add water only if needed. Give the tumbler a half turn. When the tumbler is filled, continue turning it each time you go to the other tumbler. Continue the process until the second tumbler is filled, then harvest the first tumbler. and continue the process. You can store finished or nearly finished compost in a metal or plastic trash can until you’re ready to use it.

As I mentioned earlier, I have a hard time finding the “browns”. Keeping the environment and expenses in mind, I don’t want to have to haul in materials especially ones that may have been sprayed with pesticides, I’d like to find good carbon sources nearby and I can think of a very good and abundant one except I’ll have to wait until Fall to get it. We’ve got huge trees all over my neighborhood. So in the Fall I’ll be going around to curbsides collecting leaves. As many as I can manage. I’ll put them in a pile and run over it with a mower a few times to shred them. One man’s trash is another man’s treasure or woman’s in this case. Since I don’t have access to these leaves now, I’ll be using whatever I can find. When finished vegetable plants dry out, I’ll use them and if nothing else, I’ll use cardboard (which I have loads of).

But there is another method much to my husband’s horror I’m willing to try called Vermicomposting. That will be in another post.

Oh yeah, and one more thing about composting. There are some things not recommended to put in the compost pile.

Some good links about composting:

Organic Gardener’s Composting by Steve Solomon

University of Illinois Extension

Composter Reviews

Compost Info Guide

Maryland University Extension


Compost Part 1: Humus

Compost is just amazing and like everything else involved with growing food; complicated. I’m reading Steve Solomon’s chapter about it and for my own sake I’m going to attempt to summarize it.

It starts with organic matter that hasn’t been broken down by the microorganisms in the soil. This organic matter will eventually break down under any circumstance but it will break down at different speeds and end in different ways according to a variety of factors. One of those factors is the carbon to nitrogen ratio (or C:N) of the organic material. Cardboard, for example, has a lot of carbon and not a lot of nitrogen. Therefore, it’s carbon to nitrogen ratio is high. Bonemeal, on the other hand, has a lot of more nitrogen and therefore it’s carbon to nitrogen ratio is low. To read more about this visit this site.

Now there’s this thing called humus (pronounced youmus, not hummus, the chickpea spread) which is the stable residue of decomposed organic matter. It’s C:N ratio is usually 12:1. Humus is like the structure of good soil. It gives it the ability to hold moisture and nutrients.

If organic matter with a higher C:N ratio than 12:1 is added to the soil, microorganisms in the soil will “burn” it’s carbon for fuel and save the nitrogen until the 12:1 C:N ratio is reached. At the end of this process the soil will have more humus and be healthier. At this point any left over nitrogen can be used by plants. Apparently, the soil holds the organic matter nutrients from the plants until the microorganisms have all they want. At this point the soil has become more fertile.

If organic matter with a lower C:N ratio than 12:1 is added to the soil, the microorganisms will convert the excess nitrogen to ammonia gas until the stable 12:1 C:N ratio is reached. The ammonia is then converted by other bacteria into water-soluble nitrates that make plants grow fast. The only problem is there won’t be any humus left after the conversion and that means less fertile soil. This is because nitrates cause soil microbes to multiply and attack humus.

This is why it’s usually best to add decomposed organic matter to soil instead of just adding organic matter especially when you want to grow something right away. Even though you will get more humus out of a higher C:N ratio, during that microorganism snack time, you’ll be basically getting nothing for the plants until snack time is over. And to make matters worse, the higher the C:N ratio, the longer it takes for snack time to be over and the longer it will take for a plant to reap the benefits of the added organic matter and the soil will actually be worse than it was before adding the organic matter, but only temporarily.

Making Fertilizer is a Life Lesson

This part really can be tricky even when following Steve Solomon’s Complete Organic Fertilizer Recipe. Once you’ve read the article read on. No need for me to summarize it.

His book made it sound like it would be as easy as going to a farm and seed store and just asking for the ingredients. For some reason I figured the suppliers, especially the organic supplier would know all about Steve Solomon and his fertilizer mix. But this wasn’t the case. I was either too small scale or just sounding like an idiot but I kind of got the feeling I was speaking Chinese.

First of all I couldn’t find seed meal and agricultural lime and the rest of the ingredients were packed in small bags, designed for the home gardener who just wants to liven up a rose bush. Either that or for them money is no object. I finally ended up ordering from this place located about 300 miles from me and paying a hefty shipping cost. I’m sure the products were top of the line though. They made me feel weird about using cottonseed meal saying it was for more acidic loving plants like blueberries. They recommended I use Alfalfa Meal instead and that’s what I’ve been using for the last 3 years.

Lime was another matter. No one had heard of agricultural lime so I used dolomite lime and gypsum instead. These, I was able to purchase at a nearby Southern States dealer.

Once I had all the ingredients, making the fertilizer was easy and kind of fun. I just used about a quart sized plastic container to measure each ingredient, mixed it all up with a shovel in a wheelbarrow and dumped the mixture into 5 gallon buckets with lids. This all cost me about $150.00 but would have been much less without the shipping cost and after 3 years I’ve only had to replenish the dolomite lime and alfalfa meal.

I did manage to get my soil tested last Fall and found I needed to add most everything except magnesium which means I’ll go a much lighter (if at all) on the dolomite lime next year. The test showed a very low level of phosphorus so I added bone meal this year although probably not nearly enough.

Actually while writing this, I’m realizing I really need to make some adjustments next year especially with my limes. Apparently I’ve been snoozing and should be using “calcitic limestone” which is probably what Solomon refers to as “agricultural lime”. I will also be adding cottonseed meal to my garden next year because after doing some research it appears to be fine to add to the vegetable garden.

Anyhow, for first time gardeners, Solomon’s recipe is great because once you find the ingredients, it’s pretty straight forward, works in improving soil and if measured and applied properly, relatively safe for the environment.  As Solomon says, once you get going with his formula it’s a good idea to get your soil tested and go from there.

So what’s the life lesson of all this? My Mom says it’s much easier to go through life not understanding. She says it’s good to not ask questions, accept that life is a mystery and leave it at that. My Dad is the opposite. He questions everything. I mean everything.

But if we just start following recipes without understanding the ingredients or how and why they are being mixed together, we may end up with a surprise. Obviously, we can’t learn or understand everything, and some surprises can be good but in the case of growing food, they usually aren’t welcomed and sometimes, can lead to disaster.

A big part of growing nutritious food in a sustainable way is understanding how things grow and how they are part of a ecosystem. Adding fertilizer can help but growing food involves many different parts all working together to form a healthy plant. It starts with the soil. Good soil means a strong plant that will be better equipped to survive  drought, wind, heavy rain, disease and pests. When mature, it will be nutritious food. No surprises needed.