Compost improves nearly every kind of soil. It loosens clay, helps sand hold water and feeds the soil life that feeds your plants. Making it at home is simpler than it sounds.
The recipe: browns and greens
- Browns (carbon): dry leaves, straw, shredded cardboard and paper, small twigs.
- Greens (nitrogen): fruit and vegetable scraps, coffee grounds, grass clippings, fresh plant trimmings.
Aim for roughly two to three parts browns to one part greens by volume. Too many greens make a smelly, slimy pile; too many browns make a pile that barely breaks down.
Keep it moist and airy
A working pile should feel like a wrung-out sponge. Turn it every week or two with a garden fork to add air. A well-balanced pile at least 3 feet across heats up to 130 to 160°F in the center, which speeds decomposition and kills many weed seeds.
What to leave out
- Meat, fish, bones, dairy and oils, which attract animals and smell.
- Dog and cat waste.
- Diseased plants and weeds that have gone to seed.
- Yard waste recently treated with herbicides.
Bins and timing
A simple wire ring, a wooden three-bin system or a closed tumbler all work. Tumblers are tidier in small yards. Finished compost is dark, crumbly and smells like earth, which takes anywhere from two months for a hot, well-managed pile to a year for a pile left alone.
Using it
Spread an inch or two over vegetable beds each season, mix it into planting holes for annuals and vegetables, or top-dress the lawn with a thin layer. For trees and shrubs, use it as mulch rather than mixing it into the planting hole.