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Sustainability

Worm Compost Bin

Worm Compost: Clarity Jones

Composting food and lawn waste has many benefits over sending it to a landfill. Landfills are often so large and compacted that decomposers, air or sunlight cannot reach the waste, so it will often remain unchanged for many years after it was deposited. Thus landfills grow to massive proportions. Composting can actually reduce a considerable amount of waste in a relatively short amount of time; it also cuts garbage bills and creates a nutrient-rich, moisture laden soil for gardening.

There are a number of ways to compost food scraps and lawn waste. One way is to put them in a compost bin and turn the pile frequently to encourage various microorganisms using bacteria to break it down. The worm bin described below is another efficient way to compost, and it allows the worms to do most of the work.

Materials Needed:

  • A bin, 16" X 24" X 8" (about the size of an apple crate), or 10 gallons (or the materials to make such a bin)
  • For wooden bins: a plastic garbage bag or other liner
  • About 50 sheets of newspaper
  • 2-4 cups of soil
  • 1 pound of native worms (about two generous handfuls)
  • Enough food each week to keep worms happy (worms eat three times their weight each week)
  • Spray water bottle, to keep bedding moist (but not soaking)
  • Small shovel

Steps:

  1. Locate or make a bin, approximately 16" x 24" x 8" or 10 gallons. It can be wooden, plastic or glass, though wooden bins should be lined with plastic (like a garbage bag or old shower curtain). Rinse the bin clean with tap water, since some residues can harm the worms that will live in it.
  2. Prepare bedding consisting of moist newspaper. Like soil, newspaper strips provide air, water, and food for the worms. Use about 50 pages and tear them into 1/2" to 1" strips. Use black and white print; color print can be toxic to the worms. Put the newspaper strips into a large plastic garbage bag or container. Add water until bedding is moist, but not dripping. Add dry strips if it gets too wet. Add the strips to the bin without compressing them. Make sure to leave pockets of air for the worms. The bin should be 3/4 full of wet newspaper strips. Sprinkle 2-4 cups of soil in the bin to ensure the presence of beneficial microorganisms. Gritty soil particles also aid the worms' digestion. Potting soil or fairly rich, moist soil from outdoors is fine.
  3. Before adding worms, measure their weight. If a scale is unavailable, estimate: two big adult sized handfuls of worms are about equal to a pound. The weight of the worms is important for knowing how much food to feed them. Add worms to bin.
  4. Bury food scraps under bedding. Feed the worms fruit and vegetable scraps that would normally be thrown away, such as peels, rinds, cores, etc. Limit the amount of citrus fruits placed in the bin. NO MEATS, BONES, OILS OR DAIRY PRODUCTS. Cut or break food scraps into small pieces-the smaller, the better. Measure the amount of food on a scale if possible. If a scale is unavailable, a quart sized container will probably hold a pound of food scraps, though this will vary with the types of food you use. Feed worms approximately three times their weight per week. Monitor the bin every week to see if the worms are eating the food. Adjust feeding levels accordingly. (One pound of worms requires 3 pounds of food per week).
  5. Place a full sheet of dry newspaper on top of the bedding. This will help maintain the moisture balance, keep any possible odors in the bin, and help prevent fruit flies from making a home in the bin. Replace this sheet frequently if fruit flies are present, or if bin gets too wet.
  6. Cover the bin with a lid made of plastic, plywood, or cloth, but leave the lid ajar so the bin receives some air. If desired, drill small holes into the bin. Place the bin away from windows and heaters.
  7. To keep worms happy, feed them about once a week. If bedding dries up, spray with water. (If bedding gets too wet, add dry newspaper strips.) Fluff up bedding once a week so the worms get enough air.