From time to time, you might find some other critters vying for space with your worms in their bin. It’s important to identify and eliminate harmful pests before they can multiply or harm your worms. Below are some common critters you might find: millipedes, centipedes and mites. Find out what they’re doing in your bin, and ways you can best get rid of them.
Millipedes are big, rounded wormlike creatures with their defining set of hundreds of tiny legs (though their name means “1000 legs,” it’s usually more like 400). They are slow-moving creatures that usually live in soil or plant matter. Most range from a half inch to two inches long, and their main duty is eating dead and decaying plants.
Though millipedes look a little creepy, almost all species are actually beneficial to your garden and harmless to your worms! They are not true pests. You’ll usually find them in the bin if you’re using composted plant material or manure for bedding. They are only there to perform the same job as your worms by breaking down organic matter. There is no need to remove or kill them, but if you’d rather not have them there, it’s easy to pluck them out by hand without any harm to you or your worms.
Centipedes are recognizable by their long flat bodies with the telltale 100 legs. They usually live in soil or humus and under objects like logs, rocks, and bark. They range from one inch to one foot long and come in a variety of colors, but all are predators to other animals. They run fast and kill with a set of sharp, poisonous claws, so they are certainly no friend to your worms.
If you do find that a centipede has come into your worm bin, you’ll want to remove and kill it as soon as possible before they eat your worms. The good news is that centipedes are territorial, so you shouldn’t find many in one spot. Some worm farmers say that pouring a little soda water on the centipede will stun it temporarily, but there’s not much secret to catching them. They’re fast, and you just have to chase them down as best you can and kill them with a garden trowel. Don’t worry, their venom isn’t strong enough to be lethal to humans, but their bite can be very painful, so be careful.
Mites are teeny tiny, one-fifteenth of an inch critters with eight legs. They are found nearly everywhere in the world and eat different things, from plants to other mites and creatures, depending on the species.
Mites are inevitably present in all worm bins, but you probably won’t notice them until their population has become too large, which can be well into the millions. The red mite is parasitic on earthworms, but any type of mite in large quantity is detrimental: your worms will stop coming to the surface to feed if there are too many. In general, you want to make sure your bin is not too acidic and wet, which is what mites like. Don’t overfeed (and no acidic foods) or overwater, and keep drainage holes open.
To get rid of mites already present, try one of these methods: reduce food and water input until mites start to leave; place potato slices, melon rinds, or damp newspaper on the surface of the bedding, then remove when mites have collected there; or water your bin thoroughly until mites come to the surface, then remove mites by torching, shop vacuuming, or sprinkling sulfur on them. If all else fails, replace your worm bedding entirely.