I’ve published a couple of teasers, here on this site, about composting. There was the ribbon that lasted for years, unchanged, at the bottom of the bin (Post 22, “Ribbons Are Forever”), and then the little sheets of plastic coating shed by a milk carton (Post 10, “To See the World in a Plastic Cap”). But this week’s piece will give you the full Monty. I scooped out and even tipped over the black plastic bin that’s nearest the house, where I’ve been throwing most of my kitchen scraps, rags, compostable packaging, and other miscellaneous stuff I’d love to see turn into garden soil. I may be mad, but I’m looking forward to finding out what’s happened to all of it. I always learn a lot, going through a compost bin, and I actually enjoy it.
Hope you’ll enjoy coming along for the ride on this one. I’ll get dirty for you, and let my chickens take care of the bugs I disturb, so you won’t have to.
Okay, for starters I have to admit that I’m not a “proper” composter. Don’t do as I do!
For one thing, my bins are usually on the dry side. There’s a tradeoff between water and time: the drier the bin, the longer its contents take to break down. In this desert city, compost needs more moisture than what falls from above. And I’m stingy with the groundwater. (If anything, the garden needs it!) But I throw in the hard stuff anyway: coconut shells, fruit pits, oversized twigs (little ones will vanish), cans, citrus peels, nutshells. These are all natural. If, after a couple years, they still need more time to soften, I’ll just throw ‘em back.
For another thing, I like to give things—like mystery fabrics—a chance to transform. Natural fabrics like cotton, wool, linen, and silk, will decompose, but I sometimes throw a rag into the bin even if I don’t know what it’s made of. Most likely it’s at least partly synthetic, and will stay intact and strong for years (decades? Centuries?). But if so, I can fish it out later, when I go in for the harvest, and throw it in the regular trash.
Once in a while I’ll act out of laziness, and put something mixed into the bin, such as natural cotton fabric that still has elastic sewn into it. If I’m right that the cloth is natural, it will disappear, leaving a separate strip of elastic that I never had to cut off—but now have to fish out.
I also act out of disgust sometimes. Maybe I’ve let some food spoil inside a plastic bag or other container, even one that won’t break down. If I don’t want to deal with the smelly mush, I might toss the whole thing into the compost. Later, I’ll have to pick out the bag or container, but the mush will be converted to a small amount of something soil-like and odor-free.
It’s not that I don’t know how to make pure, finished compost. I do have those dedicated bins you may have already read about—wink, wink—in Post 16, “Miracle Growth.” I limit those inputs to just four ingredients, one of them a golden liquid, full of nitrogen, and available in good quantity. When I unload that harvest, it’s homogenous, moist, earthy-dark, and ready to be spread on some nutrient-depleted patch of ground.
But the approach I’ve taken to this “kitchen” bin I’m emptying means I have to do a lot of sorting. What I shovel out isn’t ready for the gardens. It’s still got numerous objects in it.
First, the top layer. It’s recent and mostly dry. I didn’t plan ahead. I could have been putting my recent scraps in one of the other composters. But my friend Tina has given us two fence panels (nicely rusted!) that we’re installing behind the bin, so it has to be moved.
And now, from its surface to its depths, this bin goes from completely dry to moist. I rarely “turn” the contents. It’s not easy with this kind of bell-shaped composter. There’s a turning tool that goes with it, a rod with two flaps on the end that fold up when you push it in, but go out like wings when you pull it up, bringing the more finished material to the top. I find the tool hard to use. And I don’t really have to, because there’s another tradeoff—in this case, between time and degree of mixing (more mixing speeds up the process). So once again I let time do most of the work. It’s been a little over two years since I last emptied this bin. Not quite enough time.
With my hands I scoop out the dry top layer—cut paper, a tin can, fruit and vegetable scraps, wilted sprigs from a bouquet—and put it aside. Underneath it’s dark and damp. I shovel out what I can, then pull up the small sliding door at ground level. At this point I always hope the loose, fluffy contents will come spilling out. But that never happens. Things are damp in there, and packed, even “stitched” together with those uncomposted twigs and rags and such. So now it’s a matter of repeatedly plunging the shovel toward that little door from above until what’s near the opening comes out. It doesn’t take long to shove—shovel—most of the mix out the door, and then I can lift the entire bin off of what’s left.
This pile represents my work for at least the rest of the day. Not counting the top layer I’ve put aside, I’m about to start creating three new, smaller piles.
1. In the metal wheelbarrow (you saw it getting fixed in Post 9) I begin to throw all the natural, compostable material that just needs more time to break down (or more water, or more frequent mixing).
When I was a kid in Minnesota we had to throw back the fish that hadn’t finished growing to eating size. It’s the same with my compost: It has lumps that haven’t finished breaking down. Nut shells, orange peels, bottle caps, wood blocks, hardware, onion skins—these are all natural materials that will eventually transform into compost. Sometimes I’ll tear or crumble or crush the thing to help it along. I like the way wood turns soft and nails grow bigger as they rust, before they grow smaller and waste away completely.
2. In an old camp cooler I put the unnatural junk that probably won’t ever decompose.
Upper left: A Styrofoam cup. Since Styrofoam is just aired-up plastic, it won’t compost. Bottom: Unchanged (except that it acquired a certain stiffness in the bin), this plastic ribbon was made for gardeners and landscapers to tie plants and trees. How insensible! Upper right: Perhaps my compost bin was made of plastic precisely so it wouldn’t decompose along with the materials it would hold. Still, it’s falling apart. I’d rather have a container made of used wood pallets. When the pallets fall apart, you throw the wood on top of everything else, and rebuild with more scrap wood. (These black bins were sold by the city, I believe on more than one occasion, in an effort to get Tucsonans to make soil and plant gardens. I’m not going to weigh in on the correctness of that decision. These sorts of things require a kind of divine judgement.)
The main noncomposting material I’ve been finding in this process—by far—is fabric. I think I was way too optimistic about the ability of my rags to turn into soil. I’m sure that whatever grime and food spills that adhered to them were appreciated by millions of microorganisms (and some not so micro). None of that remained. I shook the dirt out of their crumply shapes and threw them in the landfill pile.
3. In the salvaged plastic wheelbarrow, I’ll slowly grow the pile of garden dirt using a coarse screen that will hold back the fragments I don’t want in it. Actually, this station is where the deciding happens: Is it hopeless, everlasting trash, or a still-recognizable natural form that will eventually go back to the earth we all come from?
Sometimes, because of mixed materials, it’s not one or the other (to bin or discard). Compostable envelopes with plastic windows. Books that decompose with glue or coatings that don’t. Here is evidence of some mixed items I found:
Top: I myself must have tossed those blue and green plastic chainlike loops in the bin, but what were they holding together? A basket? They held something natural that went away. And what about rusty bottlecaps? You find them everywhere. I sometimes use new bottlecaps as washers, and I love to watch the oxidation process give them character. But turn them over, and you’ll see a stubborn plastic lining.
My challenge is milk cartons. They’re “paper,” but coated with plastic, inside and out. I’ve been cutting them into pieces to see what happens. And I found out. The paper decomposes from the edges in. You can see this in the two pieces in the photo at right, middle. They have cream-colored centers—the paper that’s still present—and clear peripheries. Below right: I’ve peeled the three layers apart so you can see the creamy “tongue” that’s still there in this triangle. What I found most interesting was that the paper will completely decompose with the plastic layers still stuck together. I don’t know why I was surprised; it’s eaten by very tiny bugs—of course they can get in between without affecting the outer layers. Lower left: You can still see the shape of this carton, even though most of the paper is gone, and we’re left with a mess of flimsy, flyaway plastic.
I worked pretty hard on this harvesting this batch of compost, but it wasn’t without its fun and surprises, as well as hands-on discoveries (the triple-layered milk carton being my favorite):
Left: Coffee art! I found about a dozen coffee sprouts, beans still attached. Could the beans have been roasted? If not, why would I have unroasted beans, and throw them out? Well, who cares—I found my long-lost garlic press cleaner! Goodbye, at last, to punching out each hole with a toothpick. Also, somehow, two clay tools ended up in the mix, wood handles starting to disappear but the blades still like-new shiny and sharp.
Some metals, I’ve learned, don’t rust, and some do. It’s worth a look online, not overly complex:
Whole wooden clothespins and their metal springs will be chewed up by the big mouth, and maybe, just maybe, a piece of metal that’s only starting to lose its colorful, protective paint. (Oh dear, probably no flaking paint should be let into the soil at all . . . ) I throw all my canned-good cans in the bin, label and all, doubting each time that such a container could ever change its form in there. But they always do—even if some are still young fishies that need to be tossed back in.
Some readers might have been following this compost bin “dissection” with disgust, imagining slimy messes and bugs. Since my bin’s on the dry side there isn’t a lot of slime, but there are bugs of various kinds—more, yes, as you go to the wetter bottom of the pile. And I have to admit: when it comes to cockroaches, I’m a screamer. Seeing one in the house, I used to spray it with horribly strong bug spray. But I’ve found—try it!—that cleaning spray, any kind, is just as effective. I kill ‘em with window cleaner. So I was surprised to find I really don’t mind them when they’re outside. Compost is their home; it’s where they belong. The truth is, they’re my assistants. Red-orange, with black stripes that vary precisely in width like a honeybee, all shined up like your teenager’s car. Are you skeptical of my claim? Give them a chance.
This year I brought over our smallest chicken just to watch her pick off the bugs—which include roly-polys and a couple of now-familiar (to both of us) grubs. Bottom, left: This darker, firmer larva belongs to the soldier fly, a beneficial insect. The large, meaty white one is quite curious. It travels on its back with legs in the air. It grows into the scarab beetle I love, with its three-part top evoking the jewelry of ancient Egypt, and its death revealing an underside of smooth, green foil. (I plan to make something out of those shiny underparts someday. I’ve collected about two dozen specimens.) I’m a little sad when Lady Dedlock gobbles up one of the larvae—no adult beetle. But I’m blown away by her beak action. It’s a total staccato blur. As for the victim: It’s here one minute, gone the next. I’ve been thinking that’s how I’d like to die: One minute happily running or squirming, the next split second gone, more or less painlessly. I guess it would have to be a large chicken.
Below, at last, pictures of the three piles I ended up with:
Top left: All this goes in the trash can. It’s mostly rags. Top right: I’ll dump this compostable material in the now-empty compost bin for another go. Bottom. This is my reward: beautiful, organic, undesert-like soil to spread wherever. My vegetables will be happy, my pots and beds will look pretty. My well-fed food will feed me well, and it will be minutes from the picking when I eat it.
But you can do better, with more mixing, more watering, and no casual science.
I was thinking I might close by “drawing some conclusions” from this project about “changes it might suggest” for the “larger society.” What I loved most about permaculture is that the limited backyard improvements it showed me I could do always pointed to larger systems that needed to change. But I don’t think anybody needs to do any pointing. I think you get it.