How to Make Your Own Compost

Composting turns yard waste and kitchen scraps into a crumbly soil-like material called humus. Adding this humus to your garden or in new planting holes will improve your soil’s structure, health and water-holding capacity. And it’s free! Start now, and you’ll be using your homemade “black gold” by late summer and for years to come. How to proceed…

Pick a good location. Choose a spot away from your neighbors and your own back door to avoid the “organic smells.” But avoid dark spots—warm sunshine speeds decomposition—and be sure you can access the spot easily.

Select a bin. A container around three feet by three feet works best. You want it to be accessible, so the height should be between three and four feet. You can make one out of wire mesh or cinder blocks…or you can simply buy one—those basic black heavy-plastic bottomless bins work great. For instructions for building a compost bin, go to Youtu.be/9zvFresyPmA.

Get set up. Lay some branches or cut-to-fit dried cornstalks in a layer at the open bottom, right on top of the native soil, to allow a bit of air in. Place a bale of straw (not hay, which often contains weed seeds) nearby.

Start making “deliveries.” Put in the bin only “green” organic ­materials—kitchen scraps, grass clippings, spent crops and yard waste. Reminder: Chop up or mash bigger pieces to speed the composting process. Do not put in any oil, meats, bones, pet waste, plastic or ashes—these do not break down quickly, if at all, and can make your pile smelly.

Tip: Sprinkle in a bucket of garden soil now and then to introduce “worker microorganisms” to the pile. “Compost activators,” available at garden ­suppliers, also help, but just adding garden soil makes them unnecessary.

Layer. A good rule of thumb is one part “green/nitrogen” materials to three parts “brown/carbon.” Toss in handfuls from the above-mentioned straw after every delivery. Other suitable “brown” ­materials include shredded, dried fall leaves…bark…and chopped twigs.

Keep it damp. Decomposition slows to a crawl if the pile is too dry, but it shouldn’t be soggy either. Add water with the hose or a watering can to keep your compost pile moist like a damp sponge.

Stir it up. Getting air into the pile hastens decomposition. You can use the handle from an old broken hoe—it’s long and strong enough—or any similar sturdy stick. Rule of thumb: Poke and stir your compost pile weekly during the growing season.

Hot vs. cold piles. You’ll notice warmth, possibly even steam, rising off your pile at times. This is a sign that microbes are at work decomposing your deliveries. In fact, a temperature between 135°F and 155°F is desirable—the heat kills harmful organisms and pathogens.

And at this temperature, you can get usable humus in a matter of weeks or months. If you skip watering and stirring, your pile still will make compost but much more slowly. A “cold” compost pile may take a full year to decompose into usable humus.

Reminder: Stop adding compost when the weather turns colder…you can resume in the spring.