About the SFMGA

Monday, June 01, 2009

Do it with Worms

By Sam McCarthy

Backyard composting? Too hard? Too smelly? Too dry in New Mexico? If one or more of these characterizes your experience with home composting, yet you understand the tremendous benefits to our environment that this simple activity can have, behold the amazing redworm. Compared with other methods, composting with redworms requires the least labor, the least water, and in most cases, the least time to complete. The best part (so good it should be illegal) is that worm compost—castings—is simply the most fabulous compost in the known universe.

To compost outdoors with redworms, you will need the following:

  1. A bin with insulated walls, and little or no air vents. Straw bales arranged in a rectangle or square are ideal.
  2. Wet bedding filling the bin for the worms to inhabit. Examples include: loose straw, leaves, and shredded paper.
  3. Food waste from your kitchen or your friends' kitchens.

How to set up your worm bin:

  1. Arrange the bales into a rectangle. Five or six bales are about minimum for one average household.A block or stucco wall or fence can serve as one of the walls. Wet the bedding thoroughly and fill the bin at least 12 inches.
  2. After two to three days, introduce the worms. One quarter or up to one pound is adequate to begin.
  3. Begin feeding the worms kitchen waste, slowly at first. Start with one day's waste per week for the first month, then move to two days' per week for second month, and so on until the worm population has increased sufficiently to accept all the waste you produce.
  4. All food wastes must be covered by bedding, either existing bedding or new bedding applied to the surface. When bedding is no longer distinguishable from compost, more must be added to the surface. There is no such thing as too much bedding, only too little.
  5. Maintain moisture at a high level by light, periodic applications and checking corners, edges, and depth frequently. Water heavily from the top when needed.
  6. Do not turn the pile. Turning compost will invigorate bacteria to the degree that the pile may become hot enough to kill the worms.

Other materials to add:

  • Light layer of soil periodically
  • Manure in thin layers – 2 to 3 inches
  • Yard debris
  • Shredded junk mail, paper, and cardboard

A pile can be fed indefinitely, either until you wish to harvest the compost or the begins to overfill. A second layer of bales can be added. At this time a new bin must be constructed and the process started again. If roots from surrounding bushes or trees can invade the pile, a layer of plastic beneath the pile may help. Remember, bedding is both a home and a part of the worm diet. Bedding must be added to the pile in quantities approximately twice that of the food wastes.

Redworms are for sale at the SF Farmers Market on Saturdays, or call the author at 310-3971.