When houseplants start to show signs of distress, it’s most often a sign that their care needs to be improved. Requisite levels of water, light, heat, and fertilizer should be considered, first.
If your houseplants are still waning once these aspects have been sorted out, you may have a pest infestation. There are a number of pests that can make their way into our houseplants. Some of the most common include, aphids, mealybugs, spider mites, scales, soil mites, and fungus gnats.
Aside from these, there is another common, yet more benign creature that you may see in the soil around your houseplants. And that is the pot worm. So let’s unwrap, on how to get rid of pot worms.
- Types of Worms in Potted Plants
- Are Pot Worms Good Or Bad For Houseplants
- Why Do I Have Pot Worm In My Houseplants
- How To Get Rid Of Pot Worms
- Prevent Tiny White Worm Infestation
- FAQ’s Tiny White Worms In Pots
Now, before you start wondering how to get rid of those tiny white worms in houseplants or containers, it might help to understand what they are and what purpose they serve.
Pot worms, or Enchytraeidae, are part of a larger family of helminths. Helminths, being an ancient Greek term simply meaning ‘worm’, typically have elongated, flat, or rounded bodies.
In the case of our pot worms, they are rounded and look like mini earthworms.
Similar to the earthworms we love having in our gardens, pot worms spend their days eating decaying plant material and giving beneficial aeration to soil and compost.
How they end up inside your home and houseplants is simply a matter of them hitching a ride from outside. Recycled outdoor soil used for repotting household greenery is their most frequented method of transportation, however, they can also find their way in via newly purchased plants.
Types of Worms in Potted Plants
When we discover unexpected guests in our garden soil and potted plants, it’s important to identify them and determine their intentions. The presence of some can be detrimental to our plants, while others are quite beneficial.
In October 1881, Charles Darwin wrote, “There are few animals which have played so important a part in the history of the world than the earthworm”.
There are three different worm categories that work their way through the ground and potting soil. These are nightcrawlers, red wigglers, and nematodes. Let’s take a closer look at each:
Nightcrawlers – Nightcrawlers, including pot worms, are beneficial invertebrates that provide natural aeration to the soil. They also serve to loosen dense soil, such as hard clay and dry dirt, while consuming decaying plant matter for the benefit of live ones.
Red Wigglers – Highly prized by organic gardeners for their worm castings, these produce both a natural fertilizer and an effective pesticide against insect infestations.
Fungus Gnat Larvae – Not so highly prized are these tiny, white worm-like creatures. Its first choice of food is organic mulch, leaf mold, and compost. If these aren’t available, they’ll feed on and decimate plant roots. Ultimately killing the plant.
At first glance, pot worms and gnat larvae may seem similar. But their behavior and feeding habits are not. A closer look will reveal several distinct differences in appearance, to help you determine whether or not to eliminate them from your soil.
Pot worms are roughly one-quarter to one inch long and 1 or 2 millimeters in width. Their elongated bodies have a white translucence to them and they feed on organic waste material like fallen leaves, spent flowers and foliage, kitchen scraps, and composted wood.
Gnat larvae also have translucent bodies but are only a fraction of the length of a pot worm at 5-7mm. Similar to Pot worms, they have distinctive blackheads. Once mature, they become flying gnats.
Like pot worms, gnat larvae also feed on organic waste. But, with such ravenous appetites, they quickly run out and move onto the root systems of plants.
The scientific name for pot worms “Enchytraeidae” derives from the ancient Greek word for ‘of the earth’. This is apt because they quite literally eat, breathe, reproduce and benefit the soil.
Pot worms spend their days burrowing through the surrounding terra firma, losing and aerating dense soil and releasing natural fertilizers by way of their castings.
Despite our understanding of how beneficial these tiny bugs are to our gardens, little formal study on them has been conducted.
So far, we know that they reproduce rapidly. If left undisturbed, their number can reach an astounding 2500 worms in just one square foot of ground.
They prefer moist, slightly acidic environments which allow their smooth bodies to glide through the soil unimpeded.
Like earthworms, they’re rarely attracted to live plants as a food source. They prefer organic matter that has fallen within easy access and has begun to decay.
One or two tiny white worms in houseplants can actually be beneficial to the health of both plants and soil. Especially if the soil was originally lacking in aeration and nutrients.
Worm castings can naturally reduce acid-forming carbon in potting soil. This type of carbon is often left behind when frequent watering washes away vital micronutrients like calcium and magnesium.
Castings also organically increase accessible nitrogen in the soil, allowing for healthy foliage formation and photosynthesis.
These castings result from consumed plant material that has fallen. But, worm castings can also be purchased as fertilizer without risking damage to your home’s greenery.
On the flip side, because they reproduce so quickly, it is probably best to consider how to get rid of pot worms. The reason is, once all fallen plant material has been consumed, they’ll have no choice but to look to your houseplants for sustenance.
Living below the soil line, their first target will be the roots. Once severe damage to those roots occurs, plants are left unable to absorb moisture or vital nutrients.
Competition for food, in a relatively large population that has been left unchecked, can make for the quick destruction of any plant.
Luckily, the appearance of tiny white worms in houseplants is rare, especially if you’re in the habit of only using fresh, sterile soil when repotting.
Using ground soil or reused soil from outdoor containers could be an invitation for them to come inside. This is true for fungus gnat larvae, as well.
Indoor potting soil that has a relatively low pH and is kept moist, such as with ferns, creates an environment that is perfect for pot worm habitation. When repotting or dividing plants that prefer consistently moist soil, it’s imperative that a fresh, potting medium be used.
In warm coastal regions, humidity is typically high in summer. This humidity passes into our homes when we open our windows to let the cool afternoon breezes in.
But, this higher humidity, together with moist soil and a low pH, also contributes to an attractive environment for pot worms.
Quality houseplant care should include the removal of any fallen plant material. I “groom” my plants every time I water them. This will deprive pot worms of their chosen food source if you have them.
They may then look to your plants, but this evidence of them will give you the opportunity to eliminate them before they eliminate your plants.
As gardeners, we understand the issues that come with over-watering. Chlorosis (the yellowing of leaves) is a common symptom of excess moisture. Lots of moisture and fallen plant material to feed on are exactly what pot worms are looking for.
Most plants prefer for the soil to dry out before being watered again. Following this guideline can keep pot worm populations in check.
Because they breathe through their skin, moist soil is critical to their survival. If their skin dries out, they can’t breathe, and they are unable to move through soil freely. Without moisture, they’re stuck.
Watering your plants well, when needed, will provide the right environment for pot worms to aerate your soil and benefit your plants.
Allowing the soil to dry out in between waterings will motivate pot worms to occasionally seek moisture elsewhere, thereby minimizing the risk of them feeding on your plants.
Every plant has its own pH preference. Many fall into the same healthy pH range, contributing to effective plant groupings.
Maintaining adequate pH levels is essential to optimal health and resistance to disease and pests. Pot worms can become if soil pH isn’t periodically monitored.
Not only will a low pH block vital nutrients from being absorbed, but it also creates the ideal pot worm breeding ground. Considering how quickly they multiply, this could result in strong competition for food, expanding to your plants.
Sharing a love of acidic soil, pot worms are particularly common around hydrangeas and azaleas. But again, allowing the soil to dry out, around these, in between waterings, will help ward off any damage to the plants themselves.
I tend to leave any fallen flowers or leaves on the ground, to give any earth or pot worms something to focus on besides my plants.
Houseplants grow well in a humidity range of 70-80%, while garden plants thrive at around 50%. Altering humidity around houseplants is easy enough if you suspect a worm infestation.
Of course, there are plants that prefer lower humidity. But this is typically outside of a pot worm’s comfort zone. For example, you probably wouldn’t find a pot worm in the same pot as a cactus.
Since humidity is moisture in the air, pot worms feel the higher the environmental moisture content, the better.
This ensures their ability to move freely, breathe easily and reproduce faster. Pot worms can lay a vast number of eggs at one time and those babies will reach reproductive maturity within 4-To 6 weeks.
Higher-than-tolerable humidity can leave house and garden plants more susceptible to infections and pests, in general. So, it’s important to monitor humidity levels if your area is prone to pot worm infestations.
Enchytraeidae feast quite happily on decomposing plant matter like fallen or decaying leaves (autumn is their favorite season!), dropped fruit, and spent flowers.
Allowing this material to build up around the base of your plants could invite a higher population of pot worms than is beneficial to your garden. As previously mentioned, this is especially true for acid-loving plants and shrubs. Which should be cleared of debris routinely.
If you normally add well-aged compost to your garden beds, this compound may already have pot worms in it. They aid in the decomposing process by consuming it, then enriching it with nutrients via their castings.
If you do find pot worms in your compost, don’t fret. Transferring them to your garden beds along with all that garden gold is a good thing. Provided you maintain adequate moisture, pH, and nutrient levels that is. Overdoing it is when pot worms become a problem.
If pot worms do become a nuisance either in houseplants or in the garden, the question of how to get rid of them arises.
There are several ways to accomplish either completely eliminating them or gathering them together so that you can safely move them to a place where they won’t do further harm.
Pesticides are an obvious go-to but aren’t really a great idea indoors where these toxic chemicals can mix with the air that you and your family breathe. These are better suited for outdoor applications.
Organic options, like neem oil, are far less toxic and offer you the opportunity to save your houseplants from infestation damage.
There are also options to rid your soil of pot worms that don’t require any applied substances at all.
For example, you can place a piece of milk-soaked bread on the surface of infested, houseplant soil. Pot worms will see this as an unexpected feast and come running. Once the bread is covered with large swathes of worms, you can either move them, all at once, to your garbage bin or eliminate them.
When opting for a chemical insecticide, be sure to read the label for proper use. Some are clearly marked for outdoor use only as they contain highly toxic compounds. While others are formulated specifically for blooming ornamentals.
Many are made for indoor use but only for certain kinds of plants. Using these on the wrong plant could result in its demise.
Organic insecticides will always be your best option for indoor use. There are effective choices for deterring or eliminating pot worms that you can make yourself.
- Vegetable oil spray – this combination of vegetable oil and mild soap coats the bodies of pot worms, blocking the pores through which they breathe.
- Chili Pepper Spray – a mixture of pureed fresh peppers or chili powder and mild soap, this is sprayed on foliage to ward off any pests looking to feed on them.
- Garlic spray – This garlic “tea” has a pungent smell that also serves to ward off pests.
This potent, natural insecticide is extracted from neem tree seeds and sends each life stage of pot worms into utter disarray.
Neem oil adversely affects and disrupts the internal, biological systems of worms and other insects that seek to feed on live plants.
It’s also known to be effective on powdery mildew and other fungal infections, as well.
Neem oil is toxic to pot worms but completely biodegradable and safe to use around people, pets, and wildlife.
It can be purchased readily pre-mixed or you can buy straight neem oil and mix it with some mild soap.
Replacing the soil in which these worms are found can eliminate any infestations and protect your houseplants and outdoor containers (isolating a newly purchased plant will help prevent this, too).
Before replacing the soil with a fresh batch, discard the old and sterilize the pot with a 10/90 ratio of bleach and water. Then, let it dry.
Learning how to sterilize soil is an option and can be done successfully in a few different ways, depending on the amount you’re working with. However, this isn’t always effective on pot worm eggs. Replacing the soil will be far more successful.
When changing soil, following a pot worm infestation, using fresh potting soil is a must. Carefully remove the plant from its pot and place the root ball in a large bowl of lukewarm water.
Remove excess soil (and worms) from the root ball with your fingers while in the bowl. Then, rather than using old potting soil that will remain contaminated with the infestation, repot using fresh, sterile potting soil.
Even when following these steps, those tiny worms might need a little motivation to release themselves from around the roots of your plants. Adding a tiny bit of organic insecticide to the water will force them out.
They say that an ounce of prevention is worth a pound of cure. That definitely applies to keeping tiny, white worms away.
Pot worms can be very beneficial in our outdoor garden beds. But, in pots with limited space and a lack of the kind of food these worms prefer, perhaps not so much.
The following goes a long way in warding these miniature wigglers off:
- Provide plants with optimal growing conditions. Stressed plants are vulnerable to pests.
- Check plants that are brought inside to winter-over for any signs of pests.
- Always use fresh soil to repot plants.
We’ve discussed why maintaining the right soil pH is important in deterring pot worms and other pests. So, how do you do that?
Start with a soil test. pH test strips are simple to use and will give you your soil pH in a matter of minutes.
If your pH reads too high, adding commercial-grade, elemental sulfur will lower it quickly. Or slowly, which is more beneficial for plants, by adding compost, manure, or alfalfa meal to your soil.
To increase soil pH, you can introduce some garden limestone or wood ashes to the soil.
We’ve also discussed how pot worms got into your houseplants and outdoor containers, to begin with. They may have arrived via old soil or on new plants brought into your home.
But what entices them to stay? They stay and multiply because they’re being offered a consistent food source that they enjoy. Which is any organic waste material like dead leaves that are left around the base of plants.
Make a habit of removing leaves or other plant material that has fallen onto the soil below. These decaying bits are perfect worm food and ideal breeding grounds.
Remember that pot worms breathe through their skin, making moist soil critical to their survival. If potting soil is overwatered, they won’t be in any hurry to leave because pot worm eggs need this environment to hatch.
Overwatering also leads to the yellowing of foliage and leaf drop. Allowing the soil to dry out in between waterings will motivate pot worms to occasionally seek moisture elsewhere, thereby minimizing the risk of them feeding on your plants.
Proper watering and keeping the soil clear of decaying plant material are effective practices in warding off a returning infestation.
Cross-contamination is typically how pot worms get into houseplants and outdoor containers. Re-using ground or container soil is an easy way to spread them around.
When repotting or planting new, it’s always best to use fresh, sterile potting soil. The same goes when creating those beautiful container arrangements for your garden. Ground soil is just teeming with beneficial creatures that may not have the same effect in pots or indoors.
If you’ve purchased a lovely new addition to your houseplant collection, a quarantine period of 40 days is recommended to make sure that no worm or mite hitchhikers find your other plants.