The practice of nurturing houseplants for personal enjoyment goes back to the time of ancient Babylon, Mesopotamia, and Egypt. In these tropical regions, with mild winters, people of antiquity would bring parts of their outdoor gardens into their open-air living spaces and house them in terra cotta or marble pots.
But, along with this long-standing practice has come the equally long-standing nuisance of houseplant pests.
There are tens of thousands of different soil creatures that have all adapted to serve a specific purpose in the natural world. Luckily, there aren’t that many to worry about finding in our houseplants.
But, the relatively few that are worrisome, can either be beneficial to our plants or can decimate them in a short period of time.
Winged varieties, like aphids, gnats, and whiteflies are easily seen and therefore can be targeted and eliminated. Microscopic and soil-dwelling varieties are a bit harder to see but are noticeable by the visible evidence they leave behind.
Even fewer are the ones that consume fallen plant material and expel it back into the soil as nutrients, in a quickly available form that houseplants will benefit from. These are soil mites, which are clearly more helpful than destructive.
So, how do we identify tiny white bugs in houseplant soil? Or whether they’re harmful or helpful?
Identifying Tiny White Bugs On Plants
Countless numbers of soil-dwelling creatures have been inhabiting the subterranean world of garden soil for roughly 400 million years. With each specializing in either the health and vitality of our plants or more predatory and damaging activity.
Some prefer to scavenge on the soil surface in search of food, others prefer to stay buried in the safety of the soil.
Then, there are those that like to stay close to their food source. Visibly larger pests, like aphids, may be seen feeding on the underside of leaves.
Some winged types can also be seen as they fly from houseplant to houseplant in search of sustenance. Conversely, microscopic varieties are only evident by the wispy, white webbing they leave behind.
If you find bugs in your houseplants, it’s important to identify which type you’re seeing before you take action. If their presence is beneficial, like basic soil mites, eliminating them may not be necessary.
But, if they’re the predatory variety, it could be tragic if you don’t. Here, we’ll cover the most common types of houseplant pests and how to fix the problem, when necessary.
These insects are light silver in color and have soft, scaled bodies with up to 30 “legs”. They prefer moist, warm soil and feed on the juices of plant foliage.
These are most common in ferns and other tropicals that prefer moist soil. So, to avoid creating an attractive environment for these pests, it’s best to let these plant varieties dry out a bit before watering them again.
While mealybugs are large enough to be seen with the naked eye, they often hide in the top 2 inches of soil, or in deep plant crevices, when not feeding. Further evidence of them is the cotton-like cocoons they create, on stems and leaves, to protect their eggs.
These can be removed by hand and eggs can be removed by snipping off damaged or cocoon-infested parts of the plant. The top layer of soil should also be replaced. An organic or synthetic insecticide can then be applied as a deterrent.
These range in color from red and brown to yellow and green. Often mistaken for aphids (of similar coloration), spider mites are often hard to see with an unaided eye.
These destructive pests prefer dusty, arid soil and feed on the underside of leaves with piercing mouthparts. Where they also lay their eggs.
You do want to let the soil around your plants dry out a bit in between waterings but if left too long these mites may appear.
Spider mites protect their eggs (that look like tiny translucent pearls) with a silk webbing, which can easily overwhelm a plant with a high population.
If you see this on your plants, simply wipe the area with a white paper towel. If you see reddish-brown streaks on it, you have spider mites.
Removing damaged or infested plant parts may save it, in addition to applying an insecticide. But in severe cases, the entire plant may need to be discarded.
Under a microscope, these tiny creatures display a soft, brown, or yellow body with eight legs. Most thrive in consistently moist soil and multiply as soil fertility increases. Around succulents and cacti, their numbers are far lower.
Soil mites feed on decomposing plant material that has fallen onto the soil. They then release that matter back into the soil as macro and micronutrients for our plants.
So, they basically convert fallen houseplant leaves into nutrient-rich compost overnight. And their movement, through the soil, helps to distribute those nutrients.
They also feed on other creatures, like those on this list, that are detrimental to our plants. But, in poor, dry soil, where natural food sources are sparse, soil mites may look to our plants as another option.
If their numbers grow to a point that is either visually undesirable or it just makes you feel uncomfortable to see them, keep reading for things you can do to remedy that.
Most growers are familiar with this common nuisance in the garden. But, aphids can also wreak havoc on houseplants, after hitching a ride inside on your clothes or newly purchased plants.
These pear-shaped pests come in a rainbow of colors and feed in packs. With groups of them fiercely sucking the sap out of tender, new growth, or the underside of mature leaves.
Large houseplants can usually withstand a bit of aphid activity with little adverse damage. But, a severe infestation can cause:
- Distorted growth
- Out-of-season leaf drop
- Yellowing leaves
- The premature death of young plants
Winged varieties are sometimes mistaken for spider mites. But, you’ll be able to tell the difference by their size, darker color, and communal feeding habits.
Since they’re easy to see, they’re easier to remove by spraying your plants with medium-pressure water and knocking them off into a bucket of soapy water. Then, prevent their return with an organic insecticide or essential oil spray.
These highly invasive pests are not really flown. More closely related to mealybugs and aphids, these gnat-like creatures sport a grayish body, only 1/16th of an inch long.
They feed on plant sap and lay their eggs on the protected undersides of leaves. But, being so small, they’re difficult to see.
Whiteflies can cause severe leaf and stalk damage and they can multiply in record time. So, it’s important to inspect the leaves of your houseplants for the following:
- Newly hatched bugs or eggs on the underside of leaves.
- Swarms emerging from your plants as you approach them.
- A black, sooty mold that whiteflies leave behind.
- Ants in your houseplants (ants are attracted to a sweet nectar-like substance that whiteflies secrete).
Occasionally checking for these whitefly symptoms will enable you to contain and eradicate them before their numbers grow too quickly. Once they do, it’s an uphill battle to save the plant and get rid of these pests.
There are two main reasons why these pests like houseplant soil so much. There’s ample food and – depending on the type of bug – they like the environment.
Mealybugs prefer soft plants that are fed unnecessarily high amounts of nitrogen and aren’t allowed to dry out in between waterings.
Spider mites are attracted to dusty, arid soil, low humidity, and bright sunlight. A consistent watering schedule will keep these pests at bay.
Soil mites are scavengers that are attracted to organic, rotting matter such as leaves, moss, and wood chips. An occasional clean-up around each plant, followed by a daily misting of deterrent spray will deprive mites of a food source and they’ll move on.
Aphids love any houseplant that is over-watered and/or over-fertilized and whiteflies dream of greenhouse conditions that are warm and humid.
To avoid finding any of these in your houseplants, first, make sure they’re properly cared for. This will not only contribute to healthy, thriving plants. But, will also make living on them extremely unattractive to bugs.
Are Bugs In Soil Harmful
Whilst some of these pests can be extremely damaging when it comes to our houseplants, most are unlikely to cause damage to people and pets.
Soil mites are considered completely benign and rarely come in contact with people or pets. Nor do they carry harmful contagions. However, they can act as hosts for tapeworm eggs. So, it’s best not to reuse outdoor soil to repot houseplants.
Spider mites don’t spread diseases to humans. But, they have been known to bite. Given their tiny size, you likely won’t feel it. But, red abrasions could appear on the skin.
Mealybugs can’t bite humans but are one of several pests that can transmit plant viruses from one to another. However, there’s never been a documented case of those viruses being transmitted to people or animals.
Aphids aren’t dangerous to humans or animals, either. But, they can bite if people and pets are mistaken for plants when near them.
Whiteflies are another pest variety that can transmit plant viruses from one to another. But, again, there’s never been a documented case of this happening to people or pets.
Aside from bugs or mites, you may also come across small white worms called pot worms. Although these tiny translucent worms are not harmful they often infest house plants so it is worth considering removing them just in case they reproduce in large quantities.
Getting Rid of Bugs In Soil
Houseplant pests can enter your home by traveling on something (or someone) that has come in from outside.
Bugs, of any kind, can be transferred to clothing or pet fur when brushed up against a plant where they are feeding. And with them being so small, you probably wouldn’t even see them.
But, once you do detect them, there are a number of ways to eradicate them and protect your plants from decimation.
Keeping newly purchased houseplants away from others for 2 to 3 weeks should be long enough to detect the presence of these hitchhikers.
Placing sticky, fly ribbon, stakes, or traps near infested plants can lure them out of hiding and trap them.
You can use a commercial insecticide to control population growth. But, some pests, like spider mites are notorious for developing a resistance to chemical pesticides. In my humble opinion, a good organic pesticide is worth its weight in gold.
Luckily, there are some really reliable ones that you can purchase or even make yourself, at home. In addition to incorporating some effective, preventative measures into your houseplant care practice.
When a pest infestation occurs, I recommend that you change the potting soil as soon as you can. Not only is it a proven successful first step in clearing them out, it is also considered to be the most eco-friendly. Here’s how to do it:
- Tap the sides of the plant pot to dislodge the soil from the interior
- Remove the plant from its pot and place the root ball in a large bowl full of lukewarm water
- Soak the root ball for several minutes to avoid root shock
- Remove excess soil from the root ball with your fingers while it’s still in the bowl
- Make sure there are no remaining old leaves or stems tangled in the root ball
- Repot the plant using fresh, sterile potting mix
Brand-new, right-out-of-the-bag soil is important. Re-used outdoor soil could have all kinds of critters in it.
You can purchase soil already mixed with additives that encourage good aeration and drainage. Or you can mix your own. Either way, your plants will remain happy and, hopefully, pest-free.
Another option to eliminate pests is spraying with substances that are either offensive to them or will kill them.
I mentioned that organics are the best but if you’re looking for something with a bit more punch then look for an insecticide that utilizes pyrethrins.
Pyrethrins are extracted from chrysanthemum flowers and affect the central nervous system of bugs on contact.
Considered organic by themselves, the insecticides that contain it are not. So, caution and outdoor use only are recommended.
This combination of insecticide and botanicals will mortally offend any invading pests, including spider mites, and last for several weeks.
This is actually a great follow-up treatment to use after you’ve replaced the potting soil. Just in case any were hiding on leaves or stems.
If you want to use something that’s more organic, a foliar/soil spray made from various essential oils (or just plain soapy water) has proven effective on my own houseplants on many occasions.
Natural methods are often the best choice when combating bug infestations. They’re safer to use indoors and far gentler on your plants than harsh chemical options.
Insects are also less likely to become immune to natural deterrents. Let’s take a look at a few essential oils:
Neem Oil – This natural insecticide is extracted from neem tree seeds and sends each life stage of various pests into utter disarray.
Cedarwood Oil – works to dissolve the exoskeleton and soft shells of houseplant pests, making way for their rapid elimination.
Peppermint oil – may be a pleasant scent to us, but spider mites can’t tolerate it and will be less likely to infest a plant where this oil is applied.
Spearmint – the menthol component in this oil effectively repels aphids
Patchouli – This oil, extracted from the tropical patchouli plant, has naturally evolved to repel pests that prefer equally warm climates. Like those that are attracted to houseplants.
This non-toxic solution can not only repel houseplant pests but extinguish them. The grease-cutting properties of many soaps are thought to disrupt the cell membranes of insects while removing the protective wax that covers their bodies.
Grease-cutting soaps can result in lethal dehydration when sprayed on aphids, mealybugs, and whiteflies that infest your houseplants.
But, caution is recommended for use on plant foliage that also has a waxy coating. These include ornamental figs, monsteras, jade plants, and bromeliads, among others. Spraying these plants with soapy water could result in the same kind of dehydration.
Soap alone is also not recommended. It needs to be diluted with water, in the following manner, in order to be effective.
- Whisk 4 drops of grease-cutting dish soap into 5 tbsp of laundry starch
- Then, dilute this mixture in 1 liter of water
- Spray ONLY the soil around the base of plants
- Wipe off any solution that gets on stems and leaves
When houseplants begin to show signs of distress, like drooping or yellow leaves, it’s often a signal that their care needs to be improved. Requisite levels of water, light, heat, and fertilizer should be considered, first.
But, if your houseplants are still not doing well, once these aspects have been sorted out, it may be due to a pest infestation.
It’s important to maintain your houseplants in a way that will help prevent future pest issues. Incorporating the following steps into your normal houseplant care regimen will contribute to healthy plants and soil that aren’t attractive to the common pests we’ve discussed.
- Make a habit of removing leaves or other plant material that has fallen onto the soil below. These decaying bits are perfect mite food and ideal breeding grounds.
- Maintain a consistent, even humidity level for optimal plant health. Spider mites thrive in low humidity with low air circulation.
- Occasionally wipe down your plants. Mites are attracted to the sections of leaves and stems where dust build-up has caused browning.
- Avoid overwatering. Overly moist soil is very attractive to aphids and fungus gnats.
Dealing with a pest infestation on your houseplants can be a nuisance, however, it’s a fairly simple process. Replacing old houseplant soil with fresh, sterile loam, wiping away all traces of infestations and spraying them with safe and effective insecticides, plus regular inspections can help eradicate any infestation. Plus, ward off future ones.
But, before you do, consider whether or not you should. Are you getting rid of them because they’re truly harmful to your plants? Or because you just don’t like bugs?
As we’ve seen, many pests, like aphids, whiteflies, and spider mites, can definitely do more harm than good. In this case, removal is a must.
But, simple, white soil mites contribute to the decomposition of decaying plant material. Allowing our plants access to some of the most nutrient-rich, organic materials around.
If you discover you do have a damaging pest infestation, make sure that your plants are being given only the amount of water and fertilizer they need. So as not to create a vacation resort-level “all-you-can-eat” buffet for undesirable bugs. And, remember to inspect them regularly and wipe them down from time to time too.