NC State Extension

Vermicomposting for Households

shred-newsIn 2006, the U.S. EPA estimated that 55-65% of the waste generated in the United States is residential. Most of what we throw away is organic materials that could be vermicomposted, composted, or recycled. Paper and paperboard products account for 34%, and food scraps and yard trimmings make up 25% (by weight).

worm-bin-holes2Organic waste is linked to climate change. Landfills are the largest human-related source of methane in the U.S. (34% of all methane emissions). Food residuals are the second biggest source of methane in landfills.

Video: How to Set Up a Worm Bin

  1. What is the importance of vermiculture to our environment?Vermiculture turns “waste” organic materials into a valuable product (vermicompost) that enhances soil by increasing its porosity, water-holding capacity, texture, and reduces erosion. Vermicompost may also helps plants grow bigger, increase crop yields, and decrease plant diseases and pest attacks.
  2. What type of earthworm do I use for vermicomposting? Of the 9,000+ species of earthworms, only seven species have been identified as suitable for vermicomposting. The most commonly used earthworm species is Eisenia fetida.
  3. Where do I obtain Eisenia fetida (red wigglers) for vermicomposting? Do not buy earthworms from a bait shop. You need at least 1,000 Eisenia fetida (about 1-pound in weight), and bait shops only sell about a dozen worms per cup. Buy Eisenia fetida by the pound from an earthworm grower.
  4. What conditions are ideal for raising Eisenia fetida earthworms?Proper temperatures, moisture, oxygen levels, and pH should be maintained. Temperature limits are between 55 and 85 degrees Fahrenheit, with around 70 degrees being ideal. As temperatures go farther below or above these limits, the worms will decrease the amount they eat and breed. Moisture limits are 60 to 85 percent, with 80 percent being optimum. Oxygen is necessary, so make sure your worm bin has holes to allow air to flow through. Try to maintain a pH of 7.0 in the bin.
  5. How often do I feed my earthworms? Eisenia fetida earthworms will consume about 25% of their body weight per day. The number of earthworms you have is measured in pounds; there are approximately 1,000 Eisenia fetida earthworms per pound (if they are all adults, there may be 500 worms; if they are all juveniles, there could be 2,000 worms). Thus, one pound of earthworms may theoretically consume 1/4 pound of food per day. However, you should only add more food to the worm bin after the food you previously added has been consumed.
  6. How do I set up and maintain a worm bin for my home or office? Read Worms Can Recycle Your Garbage.

Publications & Resources

  • Home Composting with Earthworms Sherman, R., 2011. NC State Extension. 2 p. Simple step-by-step instructions on how to start worm composting at home.
  • Vermicomposting & Earthworm Q&A (Sherman, R., Vermicomposting News – 2013). Simple questions and answers about vermicomposting and earthworms.
  • Worm Bin Troubleshooting (Sherman, R., Vermicomposting News – 2009). Tips for taking care of your worm bin.
  • Worms Can Recycle Your Garbage Sherman, R. 2017. NC State Extension. AG-473-18. 6 p. How to set up and maintain a worm bin in your home or office to vermicompost.