The Art and Science of Composting

En español | My favorite T-shirt for working around the yard bears the phrase, "A Rind Is a Terrible Thing to Waste." On the back it reads: "I ♥ Composting." You gotta love a little gardening humor (or is that gardening humus?).

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Composting — turning unwanted organic material into a superrich soil additive for the garden — is the ultimate act of frugality. You're not only saving money by using would-be organic throwaways but also keeping your discarded orange peel, dry eggshells and coffee grounds from spending eternity entombed in a plastic garbage bag, taking up space in a landfill.

If you've priced commercially produced compost at the garden center, you know why it's sometimes called "the black gold of the garden." But it's more than the expense that makes it a treasure. Packed with carbon, nitrogen and other nutrients, compost mixed into the soil promotes healthy plant growth. When it's spread over planting beds, it helps to retain moisture, reducing the need for watering. In the end, you'll save both money and labor.

Composting is easy. Everyone can join in the rot-fest — even urban pioneers; if done properly, the mixture is odorless and of little interest to pests. Here's how:

The compost mixture is odorless and of little interest to pests. — Allan Baxter/Getty Images

• Build or buy a compost bin: Square or round, your bin should be roughly equal in height, width and depth (typically three or four feet). You can make one by shaping wire fencing into a cylinder. Or, use lumber to construct a sturdier bin. I built my compost bin, home to my beloved "Gomer the Compost Pile," out of leftover lumber from a deck building project — recycling times two! Urban gardeners might consider buying a compact plastic "rolling" compost bin from a garden center for use on decks or patios. If possible, place your bin in a shady location.

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