Compost is the ultimate symbol of nature’s efficiency. It is the result of organic matter (plant parts and food scraps) decomposing with the aid of water, oxygen, invertebrate organisms (worms, slugs, sow bugs), and beneficial microorganisms (fungi, bacteria). Crumbly, dark-brown finished compost can be incorporated into garden soil to help it retain moisture and nutrients.
Here is a step-by-step guide to getting started.
Layer it on: Successful composting depends on the right combination of “green’’ and “brown’’ material. The greens (food scraps, lawn cuttings) provide nitrogen, while the browns (dry leaves, newspaper, hay) provide carbon. You’ll need twice as much brown material as green.
Food scraps (green): Fruits, vegetables, herbs, eggshells, cooked pasta and rice, coffee grounds and used filters, and loose tea and tea bags can all be added to the pile. Do not compost meat, cheese, bones, or vegetable matter with added fats or oils, such as dressed salads.
Paper, lint, and hay (brown): Newspaper and hay make good brown matter. Shred newspaper so it doesn’t form a mat. Do not compost glossy or colored paper.
Soil (neutral): A handful (or shovelful, depending on the size of your bin) of garden soil in the middle of the pile helps to inoculate it with the microorganisms necessary for decomposition.
Garden waste (green): Flowers, leaves, grass clippings, and weeds are great candidates for the compost pile. Do not compost weeds bearing seeds, or diseased or pest-ridden foliage.
Dry leaves (brown): Autumn leaves are the cheapest, most plentiful form of carbon for composting.
From the ground up Site your bin: Full sun necessitates frequent watering; full shade slows decomposition. The bin should be convenient to a water source.
Start with brown: Begin with an airy carbon layer, ideally a loose pile of fallen leaves.
Add green: Aim for half as much green as brown. Too much green can lead to malodorous, slimy conditions.
Sprinkle in some soil: A scoop of soil in the pile encourages microorganisms.
Repeat brown and green layers: Continue layering browns and greens in a 2-to-1 ratio, ending with a layer of brown.
Keep it moist: Your pile should be as wet as a wrung-out sponge: moist but not drippy. On an open pile, use a tarp to hold in moisture or keep out rain.
Take a turn: After a week, you’ll notice the pile start to heat up. Now is a good time to turn it with a pitchfork, mixing the layers. Turning provides oxygen for the microorganisms and facilitates rapid decomposition.
Keep turning: Turn the pile weekly when it’s warm out. In winter, the pile may freeze and the process will slow.
Harvest the compost: Your compost should be done two months to a year after you start the pile. Frequent turning expedites the process. When compost is ready, it will be dark brown, free of recognizable ingredients and inoffensive to smell.
Adapted from Martha Steward Living.