Compost-ology Worm Bin Mites
Vermicomposting Troubleshooting

Problem: Excess water
This water comes from several sources. You added water to the bedding when you first set up your bin. Secondly, you add more water every time you add food waste because 80-90% of food waste is water. The third source, however, comes from the water produced by the microorganisms and worms as they break down the waste, giving off carbon dioxide and water as end products.

The water vapor produced during these metabolic processes condenses on the smooth, non-porous walls of the plastic container. This condensation water picks up dissolved nutrients as it trickles down through the vermicompost to the bottom. It is sometimes referred to as “castings tea” or “vermicompost tea.” Following are several ways to solve the problem of excess moisture.

Solution #1
Add dry bedding
Adding dry shredded paper to the surface of the worm bin very two to three weeks helps to reduce excess moisture problems. As the vapor pressure inside the bin increases, the water vapor condenses on the lid and “rains” on the new dry bedding, making it damp. Within a few days, the excess moisture distributes itself throughout the bin and water standing in the bottom is less of a problem.

According to Mary Appelhof, author of Worms Eat My Garbage, the worms seem to like the oxygen-rich layer near the fresh bedding on the surface. Regular additions of the carbon source which bedding provides also seem to improve functioning of the whole system.

Solution #2
Draw off with a turkey baster
Much of the liquid at the bottom is waste excreted by the worms and not good in their living space. Some people collect this excess liquid so they can apply diluted quantities of it to their house plants. Press a strainer into the soggy bedding in the bottom of the bin. The castings tea seeps through and is easily drawn up into the turkey baster without having bedding clog the opening.

Solution #3
Pour off or drain
Tilting the bin and holding back the bedding while you pour off the vermicompost tea is possible, but may require two people to do the job. If the previous techniques don’t work, and your bin is in a location where excess water is a continual problem, Mary Appelhof recommends drilling one hole near the bottom of one side of the bin and plugging it with a cork or rubber stopper. On the few occasions when you have to drain it, just remove the plug.

Solution #4
Make a peat-moss “worm”
A Kalamazoo worm worker, Jean DeMott, shared with Appelhof her ingenious way of dealing with excess water in her bin. She reused an old pair of pantyhose by cutting one leg off and filling it with peat moss. Closing both ends with rubber bands, she placed the giant peat-moss “worm” deep into her worm bin and let it absorb the castings tea. She then used the peat moss which contained all the nutrients from the worm bin as part of her potting mixture when she repotted plants.

Problem: Mighty Mites
One indicator of a too-wet bin is the presence of tiny red mites. Each one seems about the size of a period or a little larger. At one time people thought that mites would harm the worms, but it just turns out they are at the feed trough like all the rest of the creatures. However, they are not very attractive.

Add more bedding to absorb the extra moisture then test to see if you’ve removed the mite problem. Place a piece of white bread on the surface of the bin food overnight. In the morning, check to see if there are any red mites on it. If there are, either cut back on the amount of food in the bin or add more bedding.

Problem: Air, Food & Water – Necessary for Life
Sometimes the bin will begin to take on a sour odor, worms will be sluggish and seem to be dying. One or more conditions exacerbate this situation: not enough free air circulating in the bin, bin contents are too wet, or there is more food than the worms can handle.

To increase air circulation, first check to see that the holes in the bin have not become clogged. Aerate the bin by leaving the top off for a few hours a day until the contents dry out.

To reduce moisture level, you can add more dry shredded paper for bedding. Stir the paper so that it is well mixed into the bin to soak up the excess moisture.

For overfeeding, stop feeding the worms for four to five days. Check the bin to be sure the old food is being consumed. Dispose of food waste in your outdoor food digester or divide the worms and start another bin.

Problem: Fruit Flies
Fruit flies can be a problem, especially in the warmer months. Bury the food waste in the bedding so they won’t have easy access. However, fruit flies sometimes are brought into the bin on fruit peels. To rid the bin of these pests, pour of cup of apple cider vinegar in an open container and set it beside the bin. It will attract the fruit flies and they will drown. It is important to not put the container in the bin — if it tips over the acidity will kill the worms.

Problem: Molds, Fungi, Yeasts
This is only a problem if someone who helps to care for the bin has allergies. Very few people are affected by the natural breakdown of waste food in the bin. The allergy affected person can be in charge of other activities such as harvesting and using castings in the garden.