How to Identify and Control 11 Common Houseplant Pests

I’m guessing that you’re here because you suspect or know that there is some kind of creepy critter crawling on your orchid, philodendron, or succulent.

Do you want to know the secret to ridding your houseplants of pest problems?

No, it’s not a big old vat of insecticide, it’s being able to identify the specific pest that’s causing the issue.

With a solid identification, you can then take steps to address it and prevent future infestations.

There are 11 common pests that feed on houseplants and we’ll help you identify each of them and give you some tips about how to deal with an infestation.

Here’s the list:

In this guide, we won’t talk much about “occasional invaders” like ants, pillbugs, millipedes, slugs, and spiders.

These critters can hitch a ride on plants that are brought in from outdoors but they don’t thrive in an indoor environment. They will typically die off on their own.

Still, it helps to double- and triple-check your plants when you bring them in from outside.

With all of these pests, early identification is vital.

Make it a habit to examine your plants when you water them. Look at the top and undersides of the leaves, along the stems, and at the soil level.

And it goes without saying that healthy plants can better withstand an infestation than those that are stressed from inappropriate environmental conditions.

That means watering, feeding and keeping them in the right light exposure for the type.

Let’s start with one of the most common pests indoors and out:

1. Aphids

I’m willing to bet that if you grow plants long enough, you will come across aphids either indoors or out at some point.

Aphids are tiny sapsucking insects that feed on almost every popular houseplant out there.

There are many different species, most commonly green aphids (Myzus persicae), green peach aphids (M. persicae), and brown ambrosia (Uroleucon ambrosiae).

Some, like melon aphids (Aphis gossypii) are especially bad because they breed all year long in warm locations, like inside your home.

Regardless of the species, they can reproduce fast. One day you’re looking at just a small issue and the next you’re facing a devastating infestation.

Aphids cause leaf yellowing and distortion like curling and wilting. They can also spread diseases and kill off developing flowers. If there are enough of them, they can cause stunted growth or even kill the plant.

They leave behind a sticky substance called honeydew, and this can attract sooty mold.

In addition to these symptoms, you might see the insects themselves. They’re small, but they generally cluster together on the undersides of leaves, and on the stems, especially where the leaves meet the stems.

If you catch it early on, you can usually address the problem with nothing stronger than water. Isolate the plant and spray off the aphids with a strong stream of water.

Do this every few days until you don’t see any left on the plant. Keep the plant isolated for a few more days to be sure they’re all gone and you can move it out of isolation.

2. Caterpillars

Caterpillars are the larvae of a variety of different pest species.

None of them thrive indoors, so these are the pests that will sneak in occasionally and then die off because they can’t complete their life cycle in your home.

If you see any, just put on some gloves, pluck them off, and drown them in soapy water. Not much to worry about.

The exception is if you see worm-like critters in the soil. These grubs can infest the soil and feed on the roots of your plants.

I realize this is a petty complaint when there are pests out there that will kill your prize variegated monstera in a heartbeat. But something about them just drives me up the wall.

Fungus gnats are tiny flying insects in the Orfelia and Bradysia genera. They are small, around one-sixteenth to half an inch long, and they look similar to mosquitos, but they don’t bite humans.

They feed on fungi and other decomposing matter in the soil, not on live plant material.

So the adults won’t hurt your plants, but they will fly around being annoying. To justify my unreasonable hatred, the larvae can be a problem. They feed on plant roots, causing stunted growth and leaving the houseplant vulnerable to disease.

Fungus gnats can reproduce all year round with overlapping generations, so populations can build up quickly.

If you see the adults flying around, put some yellow sticky traps in the soil and reduce the amount of water you’re offering your houseplants.

Fungus gnats love moist soil, so if your plant can handle it, water less often with more water.

Or try the bottom watering method. If you can keep the surface of the soil dry while providing moisture, as happens with bottom watering, it can help to reduce populations dramatically.

4. Leaf Miners

Leaf miners are fairly uncommon, though not unheard of, on houseplants.

If you take your plants outside during the warm months or you just brought home a new addition, they might hitchhike along.

But even if leaf miners are present they’re mostly just a cosmetic issue. In other words, leaf miners shouldn’t cause you to lose any sleep.

The adults are tiny, harmless pests, but the larvae tunnel into the foliage, leaving maze-like trails behind.

They’re most commonly seen on vegetables, but being opportunistic they can impact many different species.

My favorite way to get rid of leaf miners is to gently smash the leaf between my fingers to crush the tunnels and any bugs inside.

Otherwise, pluck off any symptomatic leaves and spray the surface of the soil and all over your houseplant with a spinosad-based pesticide.

Learn more about leaf miners and how to deal with them in our guide.

5. Mealybugs

Mealybugs (Pseudococcus spp.) are super sneaky.

Until populations build up dramatically, they can be hard to spot because they are flat and immobile so they almost blend in with the stems.

Plus, they like to hide in nooks and crannies so you can’t see them even if you do know what to look for.

The adults are oval and flat, without wings. Most have a waxy coating, but some don’t. The coating can be clear, brown, or white, and the pests themselves can be anywhere from cream to black in color.

Citrus mealybugs (Planococcus citri) are the most common species found on houseplants. They’re covered in a fluffy, white, waxy coating.

Before you bring any new plant into your home, quarantine it for a week or two and examine it carefully and repeatedly. Look for both the pests themselves and their cottony white egg sacs.

Mealybugs use their sucking mouthparts to feed on sap of the plant, causing symptoms like yellowing or speckled foliage, aborted flower buds, and stunted growth.

They also leave behind a sticky substance called honeydew. That’s a nice way of saying that they poop out the excess sugars that they consume. This attracts sooty mold, which is a whole other problem.

I’m not going to lie, mealybugs can be difficult to eliminate.

Because they hide in protected areas on the plant, and thanks to the waxy protective coating, they can be hard to find and kill.

You can wipe the pests off with a butter knife, spray them off with a strong stream of water, or wipe them with a cotton swab dipped in isopropyl alcohol to remove their protective coating.

On larger plants, you might need to prune out heavily infested areas, since it’s unlikely you’ll be able to find and kill all the pests.

Bag and dispose of the pruned parts to avoid spreading the pests to other specimens in your houseplant collection.

If you have a large infestation, scrape or wash off as many mealybugs as you can. Then, spray the plant with insecticidal soap.

Make sure to get in all the nooks and crannies to find the hiders, because the soap needs to come in contact with the pests to kill them.

Learn more about mealybugs and how to deal with them in our guide.

6. Mites

No, not spider mites, we’ll come to those later. We’re talking about the microscopic arachnids cyclamen mites (Steneotarsonemus pallidus) and broad mites (Polyphagotarsonemus latus).

Both types of mite hide in the folds of leaves and on stems, feeding on the plant’s sap.

As they feed, they extract chlorophyll and cause the plant to look sickly and pale, or take on a bronze hue.

New growth might be slow or non-existent, the foliage may curl or be distorted, and any flowers or fruits will abort.

The extra bad news is that you have no way to know they’re around until symptoms show up.

So long as you act quickly you should be able to save your plant.

The most effective way to rid the plant of these tiny mites is to submerge it, pot, soil, and all, in a bath of 110°F water for 15 seconds.

This won’t kill most houseplants, but don’t try it on a precious, tender specimen.

You can also treat the plant with a miticide or insecticidal soap. Saturate the houseplant and soil once every two weeks until new, healthy growth emerges.

7. Scale Insects

The first time I saw scale on a houseplant, I thought my specimen just had some weird bumps on the stem. I shrugged and went on with my week.

Next time I looked, the bumps had increased in number and it started to occur to me that maybe there was something wrong with my coffee plant.

Scale insects are more common on outdoor plants than those grown indoors, but if they can sneak inside on a specimen that you bring home from the store or that has been outside for the summer, they will.

There are a few species that will feed on houseplants, with hemispherical (Saissetia coffea) brown soft scale (Coccus hesperidum), fern scale (Pinnaspis aspidistrae), and lecanium scale (Parthenolecanium spp.) being the most common.

Their appearance can vary depending on the species, with some having soft bodies and others having hard shells.

Most are brown but they can be white to black. All are oval and somewhat flattened or round, and usually under an eighth of an inch long.

The females don’t move much. In most species, they lose their legs and stay put, which can make them easy to mistake for a growth or something other than pests.

Even those species that remain mobile tend to hunker down, develop a protective waxy coating, and live out the rest of their lives without moving.

To get rid of scale, dip a toothbrush or cotton swab in isopropyl alcohol and wipe it over the pests.

You can also gently scrape them off with a butterknife or wash the plant with soapy water, but if you do this, be sure to protect the soil so that it doesn’t get wet.

Learn more about how to deal with scale insects in our guide.

8. Spider Mites

Spider mites are super common houseplant pests. These tiny little arachnids are common in dry, warm environments, which is often what we find in our homes.

There are several species that you can find indoors, but the two-spotted spider mite (Tetranychus urticae) is most common.

Closely related to ticks, they resemble spiders but in miniature, with eight legs and an oval body that is under 1/50th of an inch in diameter.

The two-spotted mite is reddish-orange, but other species can be black, brown, or cream.

You probably won’t spot the arachnids themselves, unless you use a magnifying glass. More than likely, it will be the fine webbing that they weave that you’ll notice first.

The pests will also cause the leaves to turn yellow or develop yellow stippling as they use their sucking mouthparts to feed.

Because they thrive in dry climates, you can go a long way toward avoiding them if you keep the soil of your plant moist, if appropriate, and by wiping the leaves down with a damp cloth once a week. This helps remove dust anyway, so it’s a good habit to get into.

Learn more about how to manage spider mites in our guide.

9. Springtails

Before we dive in, just know that springtails – hexapods in the Collembola class – aren’t commonly found on houseplants.

These elongated brown, black, gray, or white pests look a little like fleas, and can jump in much the same manner, but they don’t hang out on humans or animals.

Instead, they prefer moist conditions and soil with lots of organic matter. If you have terrariums, the chances are good you’ll come across them.

Springtails are detrivores, which means they eat decaying plant matter in the soil. Technically, they feed on the fungi and bacteria that feed on the decaying organic matter.

The important point is that they don’t feed on your live plants, so they are more of a nuisance than a big problem.

If you’re finding them on houseplants, the solution is easy: water less often. Let the soil dry out a bit more between watering. Most plants can survive with less water than you think and the springtails will die off or move onto greener pastures.

When it comes to terrariums, hobbyists will intentionally introduce these critters because they can be a positive part of a healthy enclosed environment, so just let them be.

10. Thrips

Thrips (order Thysanoptera) aren’t as common as aphids or spider mites, but like many other critters on this list, they can piggyback on a plant brought in from outside or from the grower’s greenhouse.

Thrips leave stippled silvery markings as they use their sucking mouthparts to feed on the foliage of plants.

These long, narrow black, cream, or brown insects are minuscule, rarely larger than one millimeter in length.

The silvery speckling on the foliage is as a result of the enzymes the pests inject as they feed, but you might also see scarring and yellow halos, which come from egg laying.

They also leave black fecal matter behind as they move around.

11. Whiteflies

If you’ve ever walked past one of your houseplants and saw an explosion of flying bugs, those would have been whiteflies.

Whiteflies aren’t the most common houseplant pests, but they aren’t unheard of. They are often found in greenhouses.

Damage is limited if the population remains small, but if numbers increase, these pests can drain your plant of energy and cause the foliage to fall off.

Whiteflies are insects in the Aleyrodidae family and are closely related to mealybugs and aphids.

Like those relatives, they use their sucking mouthparts to feed on the sap in the plant. As they do, the foliage might turn yellow or have yellow speckles.

As the damage worsens, the leaves will die and fall off the plant. Whiteflies also excrete honeydew, which results in a sticky substance that covers the foliage.

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