What are Worm Castings?

Worm Castings are the organic material that has been digested by worms, in this case Eisenia fetida.

{simply put, worm $ h i t}

Earthworms derive their nutrition from many forms of organic matter in soil including decaying plant parts, decomposing remains of animals, and living organisms such as nematodes, protozoans, rotifers, bacteria, fungi. They can produce their own weight in castings every 24 hours. During the digestive process, many insoluble minerals are converted to a plant-available soluble form and long-chain molecules such as cellulose are partially broken down by bacteria in the digestive tract. Investigations show that fresh earthworm casts are several times richer in available nitrogen, available phosphates and available potash than the surrounding topsoil.
Worm castings also contain many beneficial bacteria and enzymes. The analysis of wormcastings reveals that the number of beneficial bacteria in the ejected worm casting is much higher than in the material ingested by the earthworm.

Worm Castings have many beneficial microbes which are important in:

Worm Castings have the texture of coarse coffee grounds or peat moss.

Promoting Plant Growth and Health

Improves Plant Growth: a 20% increase in plant growth and a 150% increase in root mass is possible by adding just 1 part of worm castings to 9 parts of soil!

Research has shown that Worm Castings added to the soil at low rates may result in improved disease resistance because:

Worm Castings benefits soil in many ways:

Worm Castings can be used to make compost tea (worm tea), by mixing some Worm Castings in water and steeping for a number of hours or days. The resulting liquid is used as a fertilizer.

Worm Castings fed to poultry stimulates their immune system.

Trial Results

 - Propagation -

Chrysanthemum  Rooting:

  • Incorporated 10% vermicompost into the propagation media (peat)

  • Rooting occurred over 2 weeks, after which the media was washed off the roots

  • There is an 173.5% increase in dry root mass when rooted in 10% vermicompost

  • The dark pigmentation on the roots could not be washed off

With 10% Worm Castings               With no Worm Castings

Brussels Sprouts:

Stem Diameter
Compared to the control plants (0% worm castings) the test plants are:

  • 10% vermicompost: 11.4% thicker

  • 15% vermicompost: 8.8% thicker

  • 20% vermicompost: 12% thicker

Plant Height

Compared to the control (0% vermicompost), the test plants are:

  • 10% vermicompost: 10.7% taller

  • 15% vermicompost: 9.6% taller

  • 20% vermicompost: 8.9% taller


     With no Worm Castings

With 20% Worm Castings

- Growing -

This picture shows that plants grown in 5% Worm Castings (1 part Worm Castings to 19 parts potting soil) have a dramatic increase in the number of flowers and the speed to flowering!







   With no Worm Castings                With 5% Worm Castings

- Research  Summary -

  • Increased root mass by: 3.3% 173.5%

  • Increased plant height by: 0% - 11.4%

  • Increased stem diameter by: 0.9%* - 12.4%

  • Crop cycle reduction by: 1.5% - 2.7%

  • Increased flower size by: 4% - 5.7%

- Biological Analysis -


Organism Biomass Data



Total Bacterial Biomass (g/g) 1,774 100-3000
Total Fungal Biomass (g/g) 1,896 100-300

Numbers per gram


220,382 10,000+


121,200 10,000+


10,821 50-100

Download the complete Lab Report PDF 

- Nutrient Analysis -

Our worm castings contain excellent nutrient levels as shown in the table.















(As % of dry matter basis)

- Worm Castings Production -

  • We use a two week hot composting process (>55C) to kill potential pathogens and weed seeds

  • The Worm Casting production process (6-8 months minimum) follows the hot composting and occurs in an enclosed and protected area

  • Worm Castings are screened to a ⅛ to particle size


Our Worm Castings are certified organic.

Listed by the Organic Material Review Institute (OMRI) for use in organic production. 



Worm Castings available in 1,300 lb mini-bulk bags (approximately 1.5 yards) and in 2 kg retail bags

Our certified organic Worm Castings may purchased from our online store here