Beneficial insects Harmful animals Houseplants Pesticides

When Centipedes Live in Houseplant Soil

Yes, centipedes do sometimes reside in the soil of houseplants. Photo: Palica, Wikiedia Commons

Question: I need your help. The soil of my majesty palm is full of caterpillars. Could you tell me where they come from and how to get rid of them?

Renee Bolduc

Answer: The photo you sent didn’t show any caterpillars, but instead a centipede. Besides, there probably weren’t many of them, as centipedes are rather solitary creatures.

Centipedes are not harmful to plants, but instead feed on insects and other small critters in the soil. They can actually protect your plant against its real enemies, so you might want to consider letting them live.

Difference Between a Centipede and a Millipede?

Side by side illustration of a millipede compared to a centipede.
Millipedes and centipedes are pretty easy to tell apart. Photo: guidancecorner.co

Centipedes and millipedes are distant relatives and are often confused by gardeners. They aren’t insects, but a different type of arthropod. They belong to a group called myriapods, a name that means “with many legs”.

Centipedes are generally carnivorous, have one pair of long, spreading legs per segment and also have long antennae. Most obviously, they move quickly, so catching one is quite an exploit!

Millipedes, on the other hand, are scavengers and eat detritus: dead leaves and roots, fungi, etc. So, they too are usually beneficial. However, some species are somewhat vegetarian and may chew on a few plant roots. Millipedes generally have 2 legs per segment (except on the first segments) and those are placed under their body rather than beside it. Their antennae are short. They move slowly and don’t usually try to run away when disturbed, but often curl up when they feel threatened. There are thousands of species of both.

Note that, despite the fact that the word centipede means 100 legs, they never have exactly 100 legs, but a variable number of appendages, depending on their species and maturity. The small species found in our plants rarely have more than 30 legs. You probably guessed that millipede means 1,000 legs and indeed, most millipedes have many more legs than a centipede, but still, never a thousand!

Both are nocturnal and shy away from light, hence their occasional presence in plant pots: a good place to hide from the sun.

How Do Centipedes Find Their Way into a Pot?

Majesty palm on a deck.
Typically, majesty palms are patio plants and pick up various little creatures outdoors. Photo: Martin Viette Nurseries

If your majesty palm (Ravenea rivularis) spent the summer outdoors, which is usually the case, as it is mainly sold as a patio plant, centipedes probably moved into the pot outdoors, as they love cool dark places such as a plant pot. From there, they were carried indoors when you brought your palm back inside for the winter. 

Or maybe they were already present in the root ball when you bought the plant (majesty palms are grown outdoors in the tropics, then shipped north in the summer, so could easily harbor a few creepy-crawlies). In that case, they would have then spent the whole summer in the root ball while the palm was on your deck.

On the other hand, centipedes are also found living naturally in our homes, especially in basements and bathrooms, because they need a humid environment in which to survive, so it’s also possible that the centipedes migrated into the pot from inside your home, although that’s the least likely scenario.

How to Bring Plants Indoors Without Centipedes

Pot soaking in soapy water.
To get rid of soil-living creatures of all sorts, just soak the root ball in soapy water. Ill.: Claire Tourigny from the book Les 1500 trucs du jardinier paresseux

The usual technique for removing insects hiding in the soil of houseplants that summered outdoors also works for centipedes and millipedes likewise hiding in the root ball: soaking! Fill a bucket with soapy water and immerse the pot (and therefore the root ball) in it. Let it sit completely submerged for 15 to 30 minutes, then take it out of the water and let it drain.

You can do the same indoors to get rid of the centipedes in the pot of your palm.

This treatment works in two ways: centipedes (and millipedes) are not aquatic (at least, not the species that live in plant pots) and will drown during the soaking. That is unless the soap killed them first, as it suffocates them, blocking the pores through which they breathe.

Plant roots will not be harmed during such a soaking, although you wouldn’t want to leave plants with their root ball immersed in water for days at a time, as that would deprive the roots of oxygen and could therefore lead to rot.

As you can see, eliminating centipedes from a potted plant isn’t complicated, but it does make more sense to treat the plant when it’s still outdoors, before bringing it indoors for the winter, rather than afterwards, when it’s already in the house.

Or, live and let live! After all, centipedes are a gardener’s friend.

Larry Hodgson is one of Canada’s best-known garden communicators. He has notably been editor-in-chief of HousePlant Magazine, Fleurs, Plantes et Jardins, À Fleur de Pot and Houseplant Forum magazines and is currently the garden correspondent for Le Soleil and radio garden commentator for CKIA-FM Radio. He has written for many garden publications in both the United States and Canada, including Canadian Gardening, Harrowsmith, Horticulture, Fine Gardening and Organic Gardening. He also speaks frequently to horticultural groups throughout Canada and the U.S. His book credits include The Garden Lover’s Guide to Canada, Complete Guide to Houseplants, Making the Most of Shade, Perennials for Every Purpose, Annuals for Every Purpose, and Houseplants for Dummies, as well as nearly 60 other titles in English and French. He is a past president of the Garden Writers Association (now Garden Communicators International) and the winner of the prestigious 2006 Garden Media Promoter Award offered by the Perennial Plant Association. He resides in Quebec City, Quebec, Canada.

5 comments on “When Centipedes Live in Houseplant Soil

  1. I like seeing what comes in when I bring plants in for the winter. Winter is long and dull, a few lucky insects liven it up!

  2. These are very common in redwood forests. It is odd because, just a few miles away, in the Santa Clara Valley, they are rare.

  3. Lol I think its kinda funny that someone actually thought it was a caterpillar..thatd have to be the fastest caterpillar on the face of the earth! Lol. Although I am playfully joking, I am in no way “making fun of” the lady who asked the question..after all, I only ended up here because I too was searching the internet for answers to what these creepy crawlies were that I described as “super fast moving red worm with tons of legs like a miniature centipede”..my good friend Google ALWAYS seems to know exactly what my nonsense means..she* just gets me, ya know?(*or perhaps he,or non binary🙄,w/e fits your fancy people,I’m not trying to politicize the potential gender of an internet search engine lol) so i, too, goofed on this one in my own way that probably have people laughing at me..I laugh right along with them. Idk why I had it in my mind that centipedes were larger& poisonous&a type of creature that wasn’t a normal everyday critter but more like a rare bug you’d only find in some viatnamese jungle or some remote desert rarely touched by man lol. Now I’m even more terrified to stick my fingers into the soil to gauge the moisture level of my plants.. I kinda wish I would’ve just stayed naive in my ignorant state of wander.. Lol. Are they poisonous or do they sting/bite? And after reading this it seems like its abnormal to have as large of a population as I do. You say they’re solitary creatures which is funny, as I’ve yet to ever see just one, its always 4 of more..usually, lots more. Eek. I just got the heebie jeebie goose bumps. Thats my queu to leave. Bye now! But wait, is it bad to have so many? Should I take steps to reduce the population? If so, what would those steps be?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: