1. Use opaque material such as a Rubbermaid or Tupperware container. Look for bins with greater surface area, not height. Worms will only dwell in upper inches, not at great depths.
2.Plastic containers will retain moisture and heat better than wood.
3. Drill holes in the bottom of the container for proper drainage.
4. Drill holes in the top lid for aeration.
5. Set the worm bin inside another, larger tray, an additional lid, or use another bin of the same dimension. This bottom tray will collect excess moisture from the worm bin.
6. Place the worm bin on top of bricks or wood (in the drainage tray) to allow room for the excess moisture to drain.
7. Keep the bin in an environment that is 40°- 80° F. Basements are ideal.
8. Remove the excess moisture once a week to avoid foul odors. Rinse out the bottom tray regularly.
9. Feed the bin for about two months, then move all finished compost to one side and begin feeding on the empty side.
10. The majority of the worms will migrate from one side to the other. For any remaining worms in the compost, expose them to light by leaving the lid off. Collect top compost and repeat exposure to light. Replace lid when compost is removed.
11. Do not fill up the entire bin. Worms will do best in 5-6 inches of material.
FREQUENTLY ASKED QUESTIONS
Q: What do you need to start a worm composting system at school or home?
A: All you need to start is a bin, newspaper or cardboard bedding, worms, and kitchen scraps.
Q: What do the worms eat?
A: Worms can eat all of your vegetable kitchen scraps such as melon rinds, lettuce, banana peels, vegetable peelings, etc. They also eat coffee grounds and tea bags, crushed egg shells, cardboard egg cartons, newspaper, and plain paper. Though worms can eat meat, it is NOT recommend to feed worms meat or dairy products due to the risk of attracting pests and developing foul odors in the bin. Also avoid oils, butters, and vinegars. Similarly, worms are not fond of onions, garlic, or citrus rinds.
Q: Are these regular earthworms?
A: The type of worms recommended for use in a worm bin are called red wigglers. Their scientific name is Eisenia fetida. These are a type of earthworm but are not the large earthworms that you often find deep in the ground of your backyard. There are various species of earthworms, and not all earthworms are good composters. Red wigglers used for composting will not survive outside in the winter months in the Midwestern climate.
Q: What do the worms actually do with the garbage you feed them?
A: Worms Eat Your Garbage! Though worms don’t have teeth they are able to ingest approximately half their body weight in food per day. The waste left behind is called castings and the castings help to replenish the earth with vital nutrients, stimulate plant growth, and deter pests and diseases from harming plants.
Q: Will my dog or cat bother the worms?
A: Pets do not bother a bin that has been well maintained and is odorless.
Q: Does a worm bin attract mice, rats and other pests?
A: When a worm bin is properly maintained, it is essentially odor free and does not attract pests. As the worms are actually eating the food scraps placed in the bin, the food is not rotting or creating an unpleasant odor which may attract pests. Burying the food scraps under the paper bedding will also reduce the risks of pests.
BEDDING / PAPER SOURCES
rolls from toilet paper or paper towels
paper towels (no cleaners or oils)
paper packing materials
shredded office paper
potatoes (use caution with peels and pesticides)
berries: strawberry, blueberry, raspberry, blackberry
melons: cantaloupe, honeydew, watermelon (even rinds!)
coffee grounds and filters
crushed egg shells
rice, pasta (no oil or sauces)
tea bags, string, tag (remove staple if possible)
breads (add in moderation, yeasts can create heat)
pineapple (add in moderation, juice can be fatal in high doses)
***DO NOT FEED WORMS***
shiny or glossy papers, compostable plastics, spicy/pickled foods pet waste, yard waste, grass clippings, wood, nut shells, citrus peels, too much pineapple animal waste, onions, garlic, hot peppers, oils, butter, vinegar meat or dairy products
Vermicompost, Castings and Worm Tea
COMPOST AND CASTINGS
As the worms eat your garbage, you will see vermicompost created in your bin. This nutrient rich matter can be harvested at different times and in slightly different forms. If you harvest your vermicompost a bit earlier, you may notice that there are still small pieces of food or paper present. If you allow the worms to work through the compost for a longer period of time prior to removal, the compost will be finer and in smaller particles known as castings. Castings are more intense and eventually become dangerous to your worms because of its high salt content. Always be sure to harvest the castings from your bin and give the worms a new environment to eat and thrive.
When starting seedlings or planting your garden, we recommend:
- 1/4 worm castings: For nutrients, organic matter, and structure.
- 1/4 sand or topsoil: Adds additional structure and texture to the soil.
- 1/4 perlite or vermiculite: Adds air pockets and improves drainage.
- 1/4 coconut coir: Improves moisture retention of the mix.
If you are harvesting compost during the off-season and need to store it, make sure to keep it in a plastic container or bag to maintain moisture. The nutrient-rich substance is most beneficial when moist, and can be stored for six to nine months. Outdoor storage is fine.
WORM TEA and NOT WORM TEA
The liquid runoff from the worm bin is not worm tea. It is simply the runoff from the moisture present in the foods you are adding to the bin. Use this liquid as a fertilizer for plants or lawns by mixing it 1:1 with water. Liquid will vary depending on bin climate.
To make actual worm tea, just dissolve worm castings in water:
1. Fill a gallon bucket with tap water; let sit overnight to dechlorinate.
2. Dissolve approximately one cup of worm castings in water. Stir contents thoroughly & let sit.
3. Allow compost to steep for 12-36 hours.
4. Apply compost tea with a watering can, or spray directly onto the leaves with a spray bottle. For best results use your tea immediately after steeping.