Composting is an easy way to reduce waste while improving your yard and garden soils. Backyard composting turns organic wastes—grasses, leaves, garden debris and vegetable and fruit scraps—into a nutrient-rich mixture that you can add to your yard or garden. It’s easy to get started.
Find a site
Pick a level location about 5 square feet, preferably out of direct sunlight and away from roof drainage. Check with your city to see if it has any location regulations such as a bin must be hidden from street view. A bin should be convenient for you to add materials, accessible to water and have good drainage.
Begin with a bin
Compost bins come in many shapes and sizes. Consider your yard space, convenience and how you want your bin to look.
Box compost bins are sold at The Recycling Zone. They measure 36 inches long, 32 inches wide and 32 inches tall and have a 32-gallon capacity. They come in two pieces and fit into most vehicles. They are the ideal size for backyard composting. Compost bins can also be purchased at many retail and garden stores.
You can also build your own compost bin. The following organizations offer helpful instructions on how to build a simple compost bin.
Add the ingredients
Compost piles need an equal mix of “brown” and “green” materials to feed microbes and make rich compost. “Brown” materials add carbon to the pile and include dried leaves, twigs, and wood chips. “Green” items add nitrogen and include fruit and vegetable leftovers, grass clippings and coffee grounds. Don't worry about getting the mix exactly right, as it's very easy to add material to adjust the pile's performance.
If you're just starting a compost pile, start with a layer of 4–6 inches of browns (twigs, leaves, etc.) then add a layer of greens (food waste or grass clippings).
What to put in a compost pile
- Grass clippings
- Garden debris
- Vegetable and fruit scraps
- Coffee grounds
- Egg shells
- Sawdust and wood chips
- Cornstalks and straw
What stays out
- Food with meat, dairy, or oils
- Pet feces
- Diseased plants
- Weeds gone to seed
- Ash from charcoal or coal
Find a detailed list of what can and cannot go in the compost pile at the Environmental Protection Agency’s composting page.
Maintain the pile—aerate and moisten
- Keep your compost pile aerated and moist. To get good usable compost sooner, turn the pile with a pitchfork or shovel about once each week. The microbes need oxygen or they will give off a rotten-egg smell.
- Add moisture by watering your pile if needed. The pile should be moist like a wrung-out sponge but not dripping wet.
- Let the pile heat up between turnings. Ideally, the pile's internal temperature should be between 105– 145 degrees Fahrenheit. You can use an elongated soil thermometer to take its temperature, but you don’t have to be that exact. A pile that is too hot should be aerated or it will kill the microbes. If the pile is too cool, the microbes are not working, and may need help from a sprinkling of packaged compost starter available at garden centers.
Use the finished compost
By using compost, you can dramatically improve your soil and reduce your use of fertilizers and water.
When your compost pile is about half its original height and material at the bottom of the compost pile is dark and rich in color with a pleasant, earthy smell, your compost is ready to use. Woody material may be left, but it can be screened out and put back into a new pile. A well-managed compost pile will be ready in 2–4 months in the warm season; however, an untended pile will take a year or more to decompose.
Here are few suggested uses for finished compost:
- Mix compost in with your soil to improve quality.
- Use it to fill in low spots in your yard.
- Use it as mulch for landscaping and garden plants.
- Mix compost in the soil for potted plants.
For help with composting issues, visit Ask an Expert from University of Minnesota Extension Office or download the Minnesota Pollution Control Agency’s fact sheet.
Minnesota Pollution Control Agency
Environmental Protection Agency