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Living Green

Break It Down Now

by Jason Best

On the continuum of "things I can do to save the planet," composting may seem to fall in the same neighborhood as "make my own soap" and "weave my own clothes out of hemp" -- nice if you have the time (and your idea of green living is Little House on the Prairie).

But how hard can composting be? Things rot. If you dump a pile of leaves and grass clippings in your backyard, even if you never lift a finger again, they'll turn into compost -- eventually. Of course, you can speed things up, and there are some good reasons to do so. Compost enriches poor suburban soil, delivering nutrients to your lawn and garden in a way that commercial fertilizers can't match. It keeps plants healthy and strong, which means no more nasty lawn chemicals. And if you really go great guns, you can reduce the amount of garbage you send to the landfill by upwards of 70 percent.

But we're getting ahead of ourselves (which is why most would-be composters throw up their hands and quit). Let's start with the basics.

Illustration of woman and compost pile Easy Does It
They say compost just happens, and, really, it does. Every day bacteria and other microorganisms are breaking down dead organic material and turning it into something other organisms can use. Aficionados talk about "cooking" compost (those bacteria can generate some real heat) and using "starters" to "activate" a compost pile. But all you really need is a bunch of carbon-laden material (like dead leaves) and material rich in nitrogen (like grass clippings). While you can add a handful of soil as a "starter," if you build your pile directly on the ground, all the little critters you need will find their way in on their own. You're probably not looking to become a compost enthusiast if you build a pile like this, so site it in an out-of-the-way place. Add yard waste to the top, tossing in plenty of old leaves to keep fresh grass clippings from matting down and stinking. In a year or two, look for compost on the bottom.

Illustration of man composting Some Assembly Required
Just like you, the microorganisms in compost work best in the right environment. They need plenty of oxygen, personal space, enough moisture, and a well-balanced diet. Start manipulating these factors and you start managing your compost. If you've read any hard-core composting literature, now you're thinking, "Uh-oh, this is where they start talking about thermometers and 'carbon-nitrogen ratios.'" Not at all. You can make the process more efficient without fussing over your pile as if it's a newborn. Instead of throwing materials on willy-nilly, wait until you have enough to build a pile with dimensions between 3 feet and 5 feet. Toss everything as if it were a big salad, to distribute the nutrients, and don't let the pile get too compact. Build it on old shipping pallets to help air circulate (the most common reason compost starts to smell is a lack of oxygen). Bury kitchen scraps to avoid unwanted visitors.

Illustration of woman composting Master's Program
Intensively managing compost is also known as "hot composting," for the temperatures of up to 150 degrees Fahrenheit generated by those indefatigable bacteria in the middle of the pile. Even simple piles generate some heat, but only well-managed ones will generate the hottest temperatures for any length of time. Serious composters often use a multiple-bin system, which allows for one bin to cook the compost, one to turn the compost, and one to store materials until there are enough to start a new pile. Not all bins are created equal. Check out any of the sources listed here for intelligent discussions about different types, from make-your-own- with-a-garbage-can-and-a-few-holes to space-age stackables. An expert operation can generate compost in as little as four to six weeks. So what do you do with all that rich, earthy humus? Go to for good recommendations.

There are many ways to help your compost along -- it just depends on how much time you want to devote to it. Here are a few things you can do, ranging from some of the least labor intensive to some of the most.

Build near a deciduous tree
Summer shade keeps pile moist; extra sun warms in winter.

Cover with a tarp
Helps retain moisture during dry spells, and protects the pile from soaking rain

Turn once a month
Gives oxygen and new food to hardworking bacteria on the inside

Check moisture; water if needed
Ideally, compost feels like a wrung-out sponge.

Add redworms
These worms, available at garden shops, were born to compost.

Chop up branches
Getting hard-to-digest woody materials down to size means they take less time to decompose.

Shred everything; puree food scraps
Bacteria are like your Uncle Heinrich: They have to gum their food.

In the Mix
What can you compost? You might be surprised (and this list is hardly exhaustive):

Lawn and garden
Grass clippings
Shredded wood
But not:
Diseased plants
Pressure-treated wood

Fruit and vegetable scraps
Paper towels
Coffee grounds and tea bags
But not:
Meat or meat scraps

Junk mail
Vacuum cleaner dust
Wood ash
But not:
Human or pet feces

composting books
Composting, from Smith & Hawken's Hands-On Gardener series, and Easy Compost, from the Brooklyn Botanic Garden, both offer nonthreatening advice for the novice. The Rodale Book of Composting is invaluable for serious composters. Check out for more.

For other tips on environmentally conscious living from OnEarth magazine, visit the Living Green index page.

OnEarth and NRDC do not test or endorse products. Product references are for information only.

Illustrations: Cybele

OnEarth. Spring 2003
Copyright 2003 by the Natural Resources Defense Council