This poster shows the materials needed and basic steps for how to make compost with earthworms, in small containers. The poster was created in 2018 by Chhe Chinda of the Royal University of Agriculture, with co-authors Karen LeGrand, Cary Trexler, Borarin Buntong, Kong Thong, Socheath Tong, David Miller, Jim Hill, and Glenn Young for the Horticulture Innovation Lab project focused on building safe vegetable value chains in Cambodia. 

The benefits of using earthworm compost

1. Improves soil physicochemical and biological properties by a) introducing beneficial bacteria and protein through worm droppings, b) helping plants grow well, c) keeping crops healthy, d) increasing yield and e) lowering production costs.
2. Effectively recycles agricultural and household wastes to produce high quality compost.
3. Affordable since earthworms eat cow dung and most farmers in Cambodia feed cows, making it easy for farmers to collect the dung for raising earthworms for vermicompost production at their home.
4. Earthworm compost is highly useful in raising seedlings as well as crop production.
5. Vermicomposting is becoming popular as a main component of organic farming systems.

Materials needed to get started with vermicompost

• Use 2-week-old cow dung, which has been kept away from sunlight and water at least 3 days before use (to reduce acid content and release gas)
• Coconut fibers, cut into small pieces
• Dried leaves and/or vegetable plant waste, cut into small pieces
• Watering can, to use to water every day to maintain moisture and temperature
• Black containers with holes in bottom to drain excess water, which prevents overwatering that may spoil compost and kill earthworms

How to produce compost with earthworms

1. Mix soil, cow dung and vegetable waste thoroughly. Mix in water until moisture is around 70-80 percent (Until a small amount of water comes out when squeezed).
2. Transfer mixture into black containers with holes in the bottom.
3. Add 3 percent earthworms to the container
4. Store container on shelf and water it every day to maintain the moisture and temperature.
5. After 3 weeks, harvest the compost from the container using a basket.
6. Place basket in the shade to dry the compost for 1-2 days.

How to use vermicompost:

Use compost directly: Mix 0.1 kg of earthworm compost with 5 kg of soil. Apply to field 2-3 times per month.

Use on farm:  Mix 30 percent of earthworm compost thoroughly with 70 percent surface soil collected from farm.  Another option is to replace 30 percent of the farm soil with rice husk.

See also: How to make compost in raised beds