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Vermicomposting Dangers

By Regan Hennessy ; Updated September 21, 2017
Avoid putting meat scraps in your worm bin, which can attract rats and mice.
Rats image by MoonKeeper from Fotolia.com

Although they’re quick to discuss the benefits and joys of vermicomposting, worm-compost enthusiasts may clam up when you ask them about the potential problems and dangers associated with worm farming. In most instances, the best way to avoid potential dangers in vermicomposting is to become educated about them. Being familiar with common vermicomposting dangers can help you take measures to keep these problems from occurring in your worm-compost bin.

Temperature Extremes

Few factors can disrupt the delicate balance of life in your worm compost bin more quickly than temperature extremes. According to Loren Nancarrow, co-author of “The Worm Book,” your compost worms operate most efficiently between 55 and 77 degrees Fahrenheit. Temperatures below 50 degrees Fahrenheit increase stress for your red worms, which can lead to a drastic decrease in eating and breeding. In fact, sudden or extreme drops in temperature may cause your worms to go into shock or die. Temperatures above 90 degrees Fahrenheit can be deadly for your worms, since the bin moisture levels decrease drastically at such high temperatures.

Protect your compost worm population by bringing them inside during extremely hot or cold weather. If you opt to keep your worm bin outside, monitor the moisture level daily during the summer to keep your worms from drying out. Move the bin out of the sun to a shady area with plenty of ventilation. Stack bales of straw around your outdoor worm bin during cold weather to provide extra insulation.

Incorrect Feeding Habits

Compost worms eat kitchen waste, but that doesn’t mean your bin is a garbage can. Worm deaths in your compost bin may arise as a result of too much food, too little food or inappropriate food. Provide the correct amount of food for your worms by being familiar with feeding guidelines. As a general rule of thumb, 1 lb. of worms can consume approximately 3 to 4 lbs. of kitchen scraps in one week.

Focus on providing the bulk of your worm food in the form of fruit and vegetable waste, particularly mild, sweet foods such as melons and bananas. Crush eggshells and sprinkle them into your bin once weekly to give your worms a gritty material that aids with faster digestion. Avoid meat and dairy products. This type of food waste takes longer for your worms to break down and often creates strong odors that attract problematic pests, such as rats, mice and insects.

Worm Species

Unfortunately, not all compost worms are created equal. In fact, according to Niall Dunne, associate editor with “Plants and Gardens News,” one species of compost worm may actually be eradicating native plants and salamanders in the United States. In the Spring 2004 issue of the magazine, Dunne states that the compost worm species Lumbricus rubellus consumes excessive amounts of leaf litter lying on bare soil, which disrupts soil chemistry and leads to plant death. When you purchase compost worms, opt for a non-problematic species, such as Eisenia fetida.


About the Author


Regan Hennessy has been writing professionally for 11 years. A copywriter and certified teacher, Hennessy specializes in the areas of parenting, health, education, agriculture and personal finance. She has produced content for various websites and graduated from Lycoming College with a Bachelor of Arts in English.