Houseplant Pest Guide
Whether you are an advanced or beginner house plant collector, you will inevitably experience pests. My first big pest scare was with mealybugs on a big and lush monstera adansonii. I noticed these white fuzzy specs everywhere, and naturally, freaked out when I realized they were bugs. At the time, I didn’t take any pest precautions with my plants, and unfortunately, the plant was infested beyond repair.
This Houseplant Pest Guide will introduce you classic warning signs for a pest infestation. You will also find some favorite tricks and tips for regular bug maintenance at the end of this guide. I’ve found that regularly inspecting my plants is the best way to know what is going on with them. It sounds easy at first, but as your collection grows and life gets busy as usual, it gets harder and harder to stay on top of each leaf in your collection! Now, let’s get an idea of what bugs to look out for.
Scale is a super sneaky pest because it looks so much like dirt or regular foliage stains. When checking your plant for scale, check where the leaf meets the stem. If you see little brown stain-like specs, or if your plant looks sticky or moldy, it’s time to check for scale.
Luckily, scale are immobile bugs and lock themselves into place on your plant. So this type of pest infestation isn’t likely to spread to all of the plants in your collection. Regardless, it’s important to quarantine the infested plant – make sure it’s leaves are not in contact with anyone else!
To treat for scale, start by simply picking them off your plant. Their hard outer shell keeps them protective, so simply removing them is the best way to go. You can also wet a Q-tip with rubbing alcohol and dab them individually.
If you’d like to use a spray, I recommend insecticidal soap. Once you spray down the plant, the scale can be easily wiped off. Insecticidal soap is something every plant collector should have in their arsenal. I personally like the products by Garden Safe, Bonide, and Natria. You can also mix your own insecticidal soap at home with water and a bit of dish soap!
Aphids love spending their time sucking the delicious sap out of the foliage of your plants. All of this “drinking” can cause leaf discoloration and stunted growth. If your leaves have random patches of yellow on them, then it may be time to check for aphids.
The first step is to treating aphids is to get them off your plant! Use a cloth and wipe them off; they should come off quite easily. Then you want to start with insecticidal soap and completely wet the foliage. It’s likely that you will need to repeat this soap treatment, so check the plant regularly. Within a few treatments, the Aphids should be gone.
Mealybugs are some of the easier pests to spot. They are white, fuzzy, and like to hide out under the leaves. They are often found grouped together, so if you see a cottony object on your leaves, it’s likely mealybugs.
Like scale, mealybugs can be spot treated with rubbing alcohol and a q-tip. You can also try wiping them off with a moist paper towel. Insecticidal soap is always a good place to start. After the initial treatment, wipe the leaves down weekly with neem oil. Neem oil is a great natural pest preventative and also a fantastic way to keep your foliage clean!
Make sure to check any nearby plants for mealybugs, as they like to move. When you find a mealybug infestation, it’s best to treat all of the nearby plants.
If you see little webs on your plants, then it’s time to introduce yourself to the spider mite. Spider mites like to pierce the leaves and drink the juices, leaving little marks behind. Another telltale sign is speckled or dotted foliage. They are quite hard to see with the naked eye, so these guys require careful inspection.
Insecticidal soap and neem oil are always my first steps when I spot spider mites. I also make sure to wipe the leaves down completely, getting rid of any webbing or visible bugs. If you are vigilant and repeat these steps, you will be able to get rid of them.
Spider mites are notoriously hard to get rid of on the first try. So make sure to check your plant frequently and be prepared for repeat treatments.
Fungus gnats are more annoying than anything else, and they are probably the most common houseplant pest. If you have plants that enjoy moist soil, you’ve probably experienced fungus gnats. Fungus gnats are usually found hanging around the soil of your plants. If you suddenly have little flies all around your plants, it’s time to treat for fungus gnats.
Fungicide spray (link) is a great way to manage a fungus gnat infestation. I like the one made by Garden Safe. Spraying the top of our soil weekly will do wonders. Another great way to manage an infestation is to put little saucers of apple cider vinegar around your plants. The gnats will be attracted to the sweet liquid rather than your plants, and so it’s an excellent way to catch quite a few without much labor. Another easy way to catch a lot of fungus gnats is to use sticky traps. On Amazon, you can find options for yellow plant sticky traps, even some in cute shapes!
It’s safe to say that thrips are just the worst. Not only can they severely damage and disfigure plants, but they can also outright kill them if left untreated. To get rid of thrips, you have to be very persistent. If your plants have random yellow patches, little black dots (they like to leave behind their poo), and stunted new growth, it’s probably time to look for thrips.
Quickly remove and quarantine any infested plants; thrips can spread fast. Thrips are hard to see, and the larvae they leave behind are near impossible to spot, so you will likely notice the damage before you spot the bug. Attracted to the color blue, blue sticky traps can often work for controlling adult thrips. A thorough and regular treatment of insecticidal soap or neem oil is vital. Make sure to soak both the front and the back of all of the leaves.
I am currently in an ongoing battle with thrips (I’m finally winning!), and what’s worked best for me is the Bonide Systemic Granules. You simply sprinkle them on the tops of your plant and water regularly—this a great way to control infestations of pests that like to burrow and lay eggs in your soil. If you can’t find anything that works, using an insecticide might be your only way to go. I recommend Captain Jacks Dead Bug Brew.
How to Prevent Pests
Now that we’ve gone over the most common houseplant pests let’s introduce some regular maintenance that you can do to prevent any outbreaks.
Whenever you bring a new plant into your home, it’s tempting to put it on display right away. But it’s so important always to check any new plants. Most pests enter your home by hitching a ride, so it’s best to catch them at their source.
When you have an extensive plant collection, it’s essential to be vigilant and inspect the foliage. I like to dedicate one day a week to check all of the plants in my house for pests. It sounds annoying, but finding an infestation too late is much more painful, trust me!
It’s crucial to quarantine any infested plants. Certain bugs can spread fast, so separating them from the rest of your collection is vital.
Keep your leaves clean. A regular treatment of a damp cloth or neem oil on your foliage will do wonders in the long run. Bugs will be less likely to damage plants that are regularly treated with natural preventatives.
Now that you know the most common household pests and how to prevent them, you will be able to handle any infestation that comes your way. Many of these pest infestations seem overwhelming and unbeatable when they are happening, but don’t worry. We’ve all been there, and you can get through this with some willpower and elbow grease.