Compost is partially decomposed organic matter that improves soil structure, adds nutrients, and introduces beneficial microorganisms. It's the single most useful thing you can add to any garden.
The basic formula: Compost needs a balance of "browns" (carbon-rich, dry material) and "greens" (nitrogen-rich, wet material). The rough ratio is 3 parts browns to 1 part greens by volume.
Browns: dried leaves, straw, cardboard, paper, wood chips, sawdust Greens: vegetable kitchen scraps, grass clippings, coffee grounds, fresh garden trimmings, plant-based food waste
What not to compost: Meat, fish, dairy, and cooked food (attract pests). Diseased plants (can spread disease). Dog/cat waste (potential pathogens). Invasive weeds that have gone to seed.
The three composting methods:
Cold composting — pile everything up and wait 6–18 months. Minimal effort, slow results. Good for people who don't have much material at once.
Hot composting — build a pile at least 3 cubic feet (the minimum to generate heat), water until as moist as a wrung-out sponge, and turn every 3–5 days. Temperatures reach 130–160°F, killing pathogens and weed seeds. Ready in 4–8 weeks. Requires commitment but fast.
Worm composting (vermicomposting) — red wiggler worms in a bin process kitchen scraps directly into rich castings. Great for apartments or small spaces. Bin can live indoors if managed correctly.
When is it ready? Finished compost is dark brown, crumbly, smells like earth (not rot), and you can't identify individual ingredients anymore. If you see recognizable food scraps, it needs more time.
How to use it: Dig 2–3 inches into beds each spring. Add a handful to transplant holes. Mix into container soil at 25–30%. Top-dress around established plants.