Once you’re set with a location and collection pail, it’s time to start layering and aerating. Think of your compost bin like a layered dish.
- Build a breathable base. Start with 4 to 6 inches of bulky brown materials, such as small twigs, untreated wood chips or coarse plant stalks. This helps excess moisture drain and allows air to circulate through the bottom of the bin.
- Add a layer of green materials. Use nitrogen-rich materials like fruit and vegetable scraps, coffee grounds, paper filters, crushed eggshells or fresh grass clippings.
- Cover with a thicker layer of brown materials. Add carbon-rich materials like dry leaves, shredded paper, shredded cardboard (without tape or wax) or small twigs.
- Repeat the green-and-brown layers. Continue alternating the green and brown materials as you fill the bin. Pro tip: Use approximately two to three parts browns for every one part greens by volume.
- Finish with browns. Cover your greens with 4 to 8 inches of dry leaves of another brown material. This can help reduce odors and pests.
- Monitor moisture and airflow. To keep compost from getting moldy, and to help speed up the breakdown of materials, you’ll need to mix the compost to keep air moving throughout the pile. Many indoor and outdoor bins have a tumbler feature, which makes this process easy. With a tumbler, you just crank a handle to spin the container or move paddles through the compost, and aeration is done.
Depending on the size of your pile and how often you aerate, it may take 6 months to a year before outdoor compost is ready to use in the garden. Smaller indoor composters and tumblers are generally faster, producing usable compost in as little as a few weeks. Whether fast or slow, that’s a lot of kitchen and yard waste that won’t end up in a landfill!
Common composting mistakes to avoid
To help your compost break down properly, watch out for these common composting mistakes.
Adding too many greens
Food scraps, coffee grounds and grass clippings are great for compost, but too many “greens” can make your pile wet and smelly. Balance them with “browns,” like dry leaves, shredded paper, cardboard or small twigs, to help absorb moisture and add carbon.
Forgetting to turn your compost
Your compost pile needs oxygen to break down. If it sits untouched for too long, the materials can become compacted and slow the process. Give your pile a regular mix or turn to keep air moving through it.
For most backyard compost piles, turning your compost about once a month is a good rule of thumb. If you want your compost to break down faster, turn it more often – about 2 times a week for a tumbler or every few days for an active compost pile – to add oxygen and keep the materials active.
Letting the pile get too wet or dry
Your compost pile should feel damp but not soaked. If it’s too dry, add a little water. If it’s too wet, mix in more browns like leaves, paper or cardboard to help soak up extra moisture.
Composting the wrong materials
Some items can cause odors, attract pests or introduce bacteria you don’t want in your finished compost. Avoid adding meat, dairy, fats, oils, pet waste, diseased plants or yard trimmings treated with pesticides. Stick with compost-friendly materials and your bin will be much happier.
