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Composting methods

Tools for living    Natural gardening    Composting guide    Composting methods

From open-air to hot composting, there are several composting methods - select the option that works best for you.

raking leaves

Open-air composting

Use holding bins or an uncontained pile to compost yard debris. Bins can be made of wire mesh, old fencing, wooden pallets, or wood and wire. Many types of manufactured holding bins are available for purchase.

  • Place the bin in a convenient location. A shady area is preferable to a location in direct sun.
  • Drop yard debris into the bin and water as necessary to maintain proper moisture. Turn the pile frequently to aerate and help speed the composting process.
  • Once or twice a year, harvest the finished compost from the bottom or inside of the pile.

Compost tumblers

Barrel composters, or tumblers, provide a convenient means to turn compost for rapid, pest-free decomposition. If you plan to compost a lot of fruit and vegetable scraps without a worm bin, this is a good option.

  • Add damp chopped or shredded materials until the barrel is 3/4 full.
  • Rotate barrel vigorously every two or three days.
  • Finished compost will be ready in a matter of weeks.

Hot composting

Hot composting with multiple bins is best for gardeners who have large volumes of yard debris and the desire and time to make high-quality compost quickly. A series of two or three bins can be made of wood, wire or masonry blocks. Hot piles require some effort, but the compost is typically of a higher quality, because the high temperatures kill weed seeds and many plant diseases. It can also be quicker than open-air composting.

  • Alternate layers of brown (high-carbon) and green (high-nitrogen) materials.
  • Dampen materials until they feel like a wrung-out sponge.
  • Turn and mix the materials into the next bin just after the pile temperature peaks then drops in about four to seven days.
  • If the compost feels dry, add more water. If compost didn’t heat up initially, add more high-nitrogen material (or nitrogen fertilizer).
  • Turn again after the temperature peaks.
  • Allow the compost to cool for a few weeks, then it should be ready to use.

Worm composting

Worm bins are designed for composting food wastes using red worms (Eisenia Foetida). Vegetable and fruit scraps from the kitchen are added on a regular basis; the worms eat the food waste and turn it into compost.

To set up a worm bin, you'll need:

  • a container that is wide and shallow
  • red worms
  • bedding
  • fruit and vegetable scraps from your kitchen

Fill the container three-quarters full with moistened bedding. Add the worms. Pull aside some of the bedding, bury the food waste and cover it up.

More about composting with a worm bin

For construction plans, call Metro Recycling Information below.

Need assistance?

Metro Recycling Information
503-234-3000
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503-797-1700
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