Worm compost bin produces great garden, clear conscience

One writer's tale of life as a "worm mother"

About once a week, I toss whatever food scraps I've collected into a plastic bin in my kitchen, and in less than a month they disappear. That's because the bin contains hundreds of red wriggler worms, which eat the food and convert it to "castings," which is a nice way of saying worm poop. When I open the bin, I often find the worms clumped together like a tangle of thin, pink noodles in the spot where I buried their previous meal. A few times a year, I remove a portion of the vermicompost and use it to supplement garden or houseplant soil, but otherwise I leave the worms alone. (And no, I don't touch them. I dig with a spoon.) The bin doesn't emit any odors or noise. Most visitors to my kitchen wouldn't even know the worms are there.

The creatures' ability to thrive is even more remarkable because I am, admittedly, a neglectful worm mother. In the summertime I leave the bin on the porch, where it certainly gets too hot. I tend to replenish their bedding less frequently than is recommended. More than once I have forgotten to feed the worms before going on vacation. But through it all—aside from a minor fruit-fly infestation that I ruthlessly combated with the vacuum cleaner—we'd maintained a pleasantly symbiotic relationship for about three years.

That is, until the day, a few months back, when I shuffled, bleary-eyed, toward the kitchen and noticed an odd, squiggly pattern on the hardwood floor. Fortunately (I was barefoot), I didn't enter the room before realizing that the squiggles were actually the carcasses of hundreds of dehydrated worms. I hadn't knowingly done anything unusual or neglectful, and yet the worms had somehow become dissatisfied with conditions in the bin. Perhaps their home was too wet, or contained too many citrus peels? (The problem with worms is that they can't tell you there's a problem until they're dead.) They'd expressed their displeasure by embarking on a suicidal exodus in search of dirtier pastures. And I was left with an annelid Jonestown.

Birchwood Cafe owner Tracy Singleton (top) says her restaurant recycles 90 percent of its kitchen waste through commercial compost sites or in Birchwood's garden
Alma Guzman
Birchwood Cafe owner Tracy Singleton (top) says her restaurant recycles 90 percent of its kitchen waste through commercial compost sites or in Birchwood's garden

WHY WOULD SOMEONE willingly keep hundreds of worms in her kitchen? Because the United States produces more than 30 million tons of organic waste each year, and when that material ends up in either the incinerator or the landfill, it creates far more problems than benefits. When incinerated, water-rich organic material doesn't burn efficiently or provide much in the way of BTUs. Biodegradable waste in landfills (material put down the garbage disposal eventually ends up there, too) will decay slowly, by an anaerobic, or oxygenless, process, and create methane, an extremely potent greenhouse gas. In fact, in the landfill's dark, dry conditions, organic matter is more likely to mummify than decompose. Back in the 1970s, when the anthropology professor William L. Rathje conducted a series of landfill excavation projects, his crew famously unearthed a perfectly recognizable, years-old T-bone steak. It was so well preserved that Rathje remarked, "I swear, if we brushed the dirt off and cooked it, you would eat it." If that doesn't turn you off to the idea of compostable material in landfills, I'm not sure what will.

The most obvious solution to dealing with the 10 pounds or more of compostable material each household generates per week (more than 25 percent of your trash) is to create a backyard compost pile. But not everyone has her own yard or one owned by an understanding landlord. Also, Minnesota winters can slow the decomposition process nearly to a halt, and the food scraps run the risk of attracting animals. Trust me when I tell you that sweeping up a few worm carcasses is nothing compared to trying to exterminate a rat-infested compost pile.

Hence, the worms. My adventure in vermiculture began somewhat accidentally when I received a worm-filled bin as a gift from a well-meaning friend who has several of his own. (When he showed me his worms, I may very well have remarked, "Wow," or, "That's interesting," but I am quite certain I never said anything like, "Those are amazing" or, "I'd love to have my own worms.") In any case, the bin and its contents didn't seem like the sort of thing one could return for store credit, donate to Salvation Army, or regift, and so I became responsible for 500 or so red wrigglers.

My squirm—seriously, that's the term for a group of worms—is tiny compared to the one managed by Ellen Sandbeck, who has been a vermiculture advocate and worm retailer for about 20 years and who operates the website Lavermesworms.com. A garden shed in Sandbeck's Duluth-area backyard contains two 150-gallon vermicomposting bins that look like pony-size bathtubs. When I visited, the tubs smelled of dirt, and Sandbeck dug into one of them and pulled out a pair of decomposing blue jeans.

After helping establish hundreds of home and institutional bins in northern Minnesota, Sandbeck has found even large-scale bins to be extremely low-maintenance as long as the worms have the right home, food, and bedding. The only true disaster she's experienced involved a large amount of leftover pizza crusts that went into a school bin and coagulated into a dense ball, which the worms couldn't penetrate. ("It smelled like a corpse," Sandbeck says. "All the teachers were ready to kill me.") On the other hand, one time someone added the head of a deer carcass to one of Sandbeck's bins and the worms consumed it with no trouble at all.

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