Worms may pass peat moss through their digestive system, but they do not consume it as a primary food source and provide no nutritional benefit. The material is often included in packaging for shipping worms because of its lightweight and moisture-retaining properties. Worms thrive on decomposing organic matter, and peat moss lacks the necessary characteristics to support a healthy worm colony.
Characteristics of Peat Moss
Peat moss is carbonized Sphagnum moss harvested from bogs, representing an early stage of decomposition that makes it highly resistant to further breakdown. A primary challenge is its inherent acidity, with an unamended pH typically ranging from 3.5 to 4.5, which is far too low for composting worms like Red Wigglers. This highly acidic environment is detrimental to the worm’s sensitive skin and overall health.
The material also has a very high carbon-to-nitrogen (C:N) ratio, often cited between 58:1 and 75:1, meaning it is severely nitrogen-deficient. Because of its slow decomposition rate, peat moss does not support the robust microbial populations that worms rely upon for food. It is a largely sterile medium that fails to provide the biologically active environment necessary for vermicomposting.
How Worms Digest Food
Composting worms are detritivores; they do not directly consume fresh organic waste but feed on the bacteria and fungi growing on decomposing surfaces. The microbes act as a crucial pre-digestion step, breaking down complex organic compounds into a softer, slimy gruel that the worms can ingest. A healthy worm bin must therefore be a thriving microbial ecosystem.
When the worm ingests this microbially-rich matter, it moves through the digestive tract where it is further processed. Since worms do not have teeth, they rely on a muscular organ called the gizzard to physically grind the material. This grinding action requires grit, which is typically supplied by tiny mineral particles like sand or powdered calcium carbonate from crushed eggshells.
The worm’s gut is a warm, moist environment where the microbes multiply rapidly, continuing to break down the material into absorbable nutrients. The absence of microbial life in sterile peat moss means the worm gains minimal nutritional value, even if it passes the material through its gut. For a bedding material to function as a food source, it must first support a rich population of these microorganisms.
Preferred Bedding Materials for Worms
Since peat moss inhibits microbial activity and creates an overly acidic environment, successful vermicomposting relies on using materials with a more neutral pH and easily digestible high carbon content.
Popular bedding materials include:
- Shredded brown corrugated cardboard and newspaper, which offer a high-carbon source and excellent structure that promotes aeration. These materials are generally pH neutral and retain moisture well.
- Coconut coir, derived from coconut husks, due to its excellent moisture retention and its near-neutral pH, typically ranging from 5.5 to 7.0.
- Aged manure and finished compost, which are highly beneficial as they introduce a rich supply of microbes and nutrients directly into the system.
For best results, bedding materials should be moistened before use and mixed to prevent compaction, ensuring the environment remains hospitable for the worms and their microbial food source.