Carrying on about composting

So, my brother sends me this link to an article about composters in the Wall Street Journal and asks me, "Do you have any experience with any of these gadgets?" To which I replied:

The WSJ actually missed some other elaborate, expensive, fussy composting devices that have been making the rounds of trade shows this year. Just as well.

I personally have four compost bins, all of designs too simple, dull, time-tested and practical to have qualified for that article. No, I am not speed composting. I am composting without a deadline. It works fine.

To break down my knowledge of the devices described in the Journal article:

1. Indoor composting machine: Saw it at the Museum of Science and Industry Smart Home exhibit in March 2008. Thought it was absurd. Still think so. Spend $400, plus electricity, to do something you can do for practically free? Use an electric machine to do something that various bugs and microorganisms have been doing effectively for millions of years? Please. (Speaking of which, a director of sustainability for the Sierra Club doesn't like compost when "bugs and things get on it"? Where does she think compost comes from? Bugs and things make it.)

2. Tumbler composters (including that rolling ball thing) can speed up composting somewhat, with fuss and bother, and are especially appealing to impatient people, the kind of people who can't restrain themselves from poking the chicken all the time when they barbecue. Tumblers moderately speed up the process because if you regularly shift your composting materials, you redistribute the bugs and things and their food supply, providing more opportunity for feeding and reproduction. You also mix in air, providing aerobic bacteria with oxygen, which allows them to multiply more.

Usually, the directions for a tumbler composter will urge you to chop up the plant materials before you add them. Of course that speeds up composting, because a smaller particle size increases the ratio of surface area to volume and therefore provides proportionately more surface area for the action of bacteria and bugs and things. If you cut up your plant matter before adding it to any bin, you will get faster compost. You can mince it with a chef's knife and get faster compost still.

I have enough things in my life to fuss with, so I don't need a tumbler composter.

You also can get compost faster in any bin if you carefully calibrate the proportions of carbon-rich materials such as leaves and nitrogen-rich materials such as grass clippings. I don't do that either. I just toss in whatever plant matter comes along. It doesn't break down at the theoretical top velocity or get hot enough to kill weed seeds and fungus spores, but eventually I get compost.

3. Vermiculture--worm composting--absolutely works. It can be done with a homemade worm bin made from a $10 plastic storage container with a lid and bedding made by shredding newspapers, and that's how most people I know do it. The expensive worm composters with the stacking layers make it happen a little faster and more tidily, and make it less messy (although not less fussy) to harvest the worm poo and worm pee that are the goal of the whole process.

Worm poo and worm pee (usually euphemized as "worm castings" and "worm tea") are potent soil amendments because worms have gazillions of microbes in their guts. They break down organic matter very efficiently, releasing many of its nutrients in a form plants can use. They reduce the particle size of the remainder to make it handy for other bugs and things in the soil to feed on and break down further. And the worm poo contains gazillions of microorganisms, which add to the variety of bugs and things in the soil. Healthy soil--soil that is best for plants--is soil that has lots of different kinds of bugs and things in it.

Where you can get into trouble with worms is if 1) You overfeed them, or feed them chunks of food too big to digest. They can only consume so much fruit or vegetable scraps; too much will only attract fruit flies. 2. You keep them too dry (they dry up and die) or wet (they drown, and die in an especially stinky way). 3. You are prissy about touching them. Sooner or later, no matter what kind of bin you use, you are going to have to touch a worm (and worm poo). They are of course completely harmless.

I don't have a worm bin because our basement is too hot and also is down four flights of stairs, and I am concerned that I would forget about the worms and let them starve or dry out. You don't have to fuss much with worms, but you do have to remember their existence.

Worm composting can be done in an apartment in a well-ventilated closet, but I don't have any closets near the kitchen. I've known people who keep a worm bin under the dining-room table. I'm not that hard-core.

As for outdoor compost, if I had a place out in the country, I would just have piles, and maybe turn them with a fork every couple of months. But needing to be relatively tidy in multi-unit housing in tight urban quarters, my personal bins are:

1. A bin of the type often called a holding bin. It is basically a rugged plastic perforated cube or cylinder about a yard across, with a liftable lid and a door at the bottom of one side. You put plant matter in the top, along with some soil or mature compost to get the crop of bugs and things started, and put the lid on. You keep adding stuff at the top. Meanwhile, the stuff toward the bottom is breaking down. After a few months you open the door at the bottom and, if the lowest layer of compost is done, you dig it out. You toss anything not composted back in the top. This will work more efficiently if you mix up the plant material as you put it in and if you occasionally poke or reshuffle the bin's contents to get air down into it. But I almost never do that. I have a special $35 compost-aerating tool that I haven't touched in years. Eventually I get compost.

The virtue of this bin is that it has a lid, is relatively neat so it doesn't freak the neighbors out and is fairly well fortified against varmints (although the top is now slightly squirrel-chewed). This is where I compost fruit and vegetable scraps. You can buy composters of this basic type for between $80 and $175; I think I paid about $100 for this one 10 years ago.

2 and 3. Two simple plastic bins each formed of a single sheet of sturdy but flexible black perforated plastic bent into a cylinder about a yard in diameter. I think I paid about $35 apiece several years ago. I use these for leaves, weeds and other stuff collected from the garden. I just toss it in, and after a few months I wiggle the cylinder right off -- the plastic slides nicely -- and dig out the finished compost from the middle of the resulting pile. I place the bin in a new spot, and dump in anything uncomposted to start a new batch. In the process, I have aerated the pile. I liked this method so well that I bought a second one of these bins. I hide them behind a hedge.

4. A space between our building and the building next door where I accumulate shredded leaves. Sometimes, at the bottom of the pile, I get something fine, dark and fluffy called leaf mold. It's basically what you would find in the bottom layer of leaf litter in the woods. It is different from compost because it is created entirely by fungi, with no help from bacteria, insects, arthropods and other critters. It does not pack the nutritional punch of compost, but it does improve the texture of sticky clay soil and is a good substitute for peat moss, much of which is not sustainably harvested. I rarely get leaf mold, though, because it takes a couple of years and I use up my shredded leaves much faster for mulch and as a compost ingredient.

I do use two devices to fuss with my compost: A milk crate, found in an alley, with which I sift it; and an electric blower-vacuum (they run $60-$100 at home centers), with which I vacuum up all the leaves as far as the cord will reach. Shredded leaves don't blow around or mat down when used as mulch, take up much less space than whole leaves in piles and break down faster into compost. (See particle size, above.) I am waiting eagerly for it to stop raining and for the leaves to fall so I can go out and suck them up with my leaf vacuum. I find it especially satisfying to suck up leaves other people have raked to the curb to be carted away.

Basically, you can spend as much money as you want to make compost, or none. You can fuss as much as you care too, and get as technical and precise in your formulation as your temperament and training insist upon, or you can just toss stuff in and let it do its thing. You can turn your compost pile every week or every month or hardly ever. The main difference in the result will be the length of time it takes to get usable compost.

Moral of the story: If you don't want your ear bent, don't be sending me links about composting.

Got a garden question? I recommend you call or e-mail the Plant Clinic of The Morton Arboretum in Lisle, the Master Gardeners of the University of Illinois Extension or the Plant Information Service of the Chicago Botanic Garden in Glencoe .

All contents of this post are copyright Beth Botts. Feel free to link or share a brief excerpt with a link, but please do not reproduce photos or any other part of this blog without my express permission.