Worm Composting FAQ

Frequently Asked Questions

1. I’ve got bugs in my worm bin.  What should I do?

Absolutely nothing!  Bugs, big and little, are what makes the decomposition happen.  Here are some of the beneficial critters you may find.  Tiny flies and ants can be pesky, see following questions.

2. I’ve got millions of tiny flies. What do I do?

The tiny flies are vinegar flies, which look just like fruit flies.  The first line of defense is to bury food scraps completely.   Also, make sure you are not feeding too heavily (more than a quart per week per square foot).  If you still have problems, try feeding less fruit, which is the main attractant.  Some ideas for putting any extra food scraps to good use are found in these PDF downloads: Homemade Food Scrap Composter and Burying Food Scraps

Remember that flies don’t bother the worms, and they will be less bothersome to you if your worm bin is outside, away from people.  As a last resort, cover your food scraps with a light (one-quarter inch) layer of soil, then a layer (2 - 4 inches) of brown material (leaves or shredded newspaper).

3. There are ants in my worm bin. What should I do?

Ants are usually an indication that the material in the bin is too dry.  To encourage them to leave the bin, moisten and turn it or stir it with a trowel to disrupt their colonies. 

If there are many ants in the vicinity, they may return to the worm bin.  You can exclude the worms by putting the worm bin on blocks of wood and setting the blocks in dishes of water.  Nurseries sell various products that create a sticky barrier the ants will not be able to cross.

If you don’t want to go to that much trouble, take heart!  The ants don’t bother the worms and they actually benefit the composting process by bringing fungi and other organisms into their nests.  The work of ants can make worm compost richer in phosphorus and potassium by moving minerals from one place to another.

4. I had a worm bin but my worms died. What did I do wrong?

First of all, don’t be discouraged.  A worm bin is a biological system and it may take more than one try to get it right.  Make sure you have the right kind of bedding material and it is as moist as a wrung out sponge

Remember that worms need oxygen too! Worms can easily be drowned if the worm bin is left outside during a rain, or from feeding too many food scraps without adding bedding to offset the moisture.   

Another cause of worm death is overfeeding, which can result in the food heating up in the bin (hot composting), killing the worms as temperatures climb above 90 degrees F.




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