The Questions Beginners Worry About
Oklahoma State University Extension lists a bin that is too hot, too dry or too wet as reasons worms try to escape, and too much or exposed food as the cause of odor. In other words, problems usually come from the setup and feeding, not from the worms.
If your bin starts to smell, check the food first. Too much food breaking down faster than the worms can eat it is a common cause. Cut back on scraps before changing anything else.
Choosing the Right Worm Species
Not every worm is a composting worm. Garden earthworms are a different kind and are not the ones to put in a bin. Oklahoma State University Extension recommends red wigglers (Eisenia fetida, also called tiger worms) for home vermicomposting.
Buy composting worms from a supplier that sells them for that purpose, and do not dig them up from the garden. For quantity, the same source suggests about one pound of worms per square foot of bin surface.
Setting Up a Bin Before the Worms Arrive
Get the bin ready before the worms arrive, so the bedding has time to settle to the right moisture level.
Bin Type
A plastic storage bin with a lid works. For size, Oklahoma State Extension suggests about 2 square feet of bin surface per person, and a depth of 12 to 24 inches. Make small ventilation holes around the lid and top, and larger drainage holes in the bottom with a tray underneath to catch liquid.
Bedding
Good bedding includes old compost, shredded paper mixed with soil, peat moss or coconut coir. It should be moist but not dripping: wet it, wring out the excess, and fluff it up. Spread it 6 to 10 inches deep. Keep the bin at roughly 60 to 75°F (15 to 24°C), away from direct sun and heat.
Feeding Your Worms Without Overdoing It
Start small. Oklahoma State Extension suggests a thin layer of food scraps, about 1/4 to 1/2 inch deep, per week. Fruit and vegetable scraps, coffee grounds and crushed eggshells are common choices. Do not feed greasy food, meat, dairy or pet waste.
Bury scraps in the bedding instead of leaving them on top, and feed in a different spot each time. When food starts disappearing faster, you can add more gradually.
Harvesting Your First Batch of Castings
Oklahoma State Extension says worms turn feed and bedding into finished compost in about two to five months. The finished material is dark, crumbly and earthy-smelling.
To separate worms from castings, the same source describes two methods. One is to dump the contents into piles under bright light, so the worms move toward the center of each pile. The other is to stop feeding for about a week and place a mound of moist food in the center, so the worms migrate to it.
Use finished castings in potting mix, sprinkled around houseplants, or worked into garden beds.
What to Do Next
A worm bin will not fix household waste on its own, but it is one small system that turns scraps into something useful. Start with a modest bin, feed lightly, watch the temperature and moisture, and adjust as you learn.
