Composting worms do need moisture, but too much can kill. Overly wet bins can also foster pest insect outbreaks. Give worms adequate moisture, but not too much.
The ideal moisture content for worm bins is material that feels like a wrung out sponge. Undoubtedly, enclosed worms bins will often be moister than a wet sponge. Below are some ways to keep worm bins from becoming too wet.
How to Tell if a Worm Bin is Too Wet
- Water is pooling in the bottom of the bin or underneath.
- Lots of white mites or fruit flies. The bin could be too wet or just have too much food.
- A bad smell. Too much moisture can cut oxygen in the bin and cause it to become anaerobic. Anaerobic decomposition is the kind that stinks. The aerobic decomposition in a good compost pile or a worm bin smells earthy and sweet.
How to Mitigate Moisture in Composting Worm Bins
- Be sure to have 6 – 8 holes in the bottom of the bin for fluid drainage. Smaller holes are better to prevent escaping worms.
- Do not over feed. Kitchen scraps are a common worm food, but also contain lots of moisture. Go easy. It’s easy to get excited about worms eating garbage. Excess food can be frozen or placed in a pre-composting bin.
- Add plenty of shredded newspaper or cardboard with each feeding and between feedings if necessary. Newspaper and cardboard will absorb moisture and help balance the system. Don’t be afraid to add quite a bit. Paper products provide carbon which is necessary for a proper composting environment.
- Open the lid during the day. If there is adequate light, and the bin environment is favorable, worms will not escape the bin. Open the lid and air it out.
- If it is necessary to add water, lightly spray the top with a spray bottle, cover and check the next day. Spraying will help prevent waterlogging.
In an emergency, move worms to a new bin. If worms are escaping in droves and the environment has gone anaerobic, move the worms to a fresh bin. Mass migrations of unhappy worms look like clumps of worms on the sides or in one area of the bin.
Bugs in the Worm Bin
Most critters in the worm bin won’t do any harm, but if populations explode, they can be a nuisance. Here are some tips to deal with outbreaks. First, place a thick layer of shredded newspaper on top of the food and compost. This helps create a physical barrier.
- Fruit flies can be controlled with fruit fly traps in and around the bin. Traps can be made from small containers filled with vinegar or citrus peels. Cover the top with foil and punch small holes in the foil. Fruit flies will enter, but have a hard time finding their way out. Sticky traps attached to the lid of the bin on both sides also work well.
- Fungus gnats are a small, black, flying gnat which can be a nuisance. Add some coffee grounds to the bin. One serving will do. If the pests persist, then they weren’t fungus gnats.
- Houseflies in the bin are an indicator of exposed, rotting matter, and that the holes of the worm bin are too large. Cover the holes with screen and cover the contents of the bin with newspaper.
These tips should help keep a balanced composting worm bin. A balanced bin is a healthy bin.