You might mistakenly believe that, due to their large, robust leaves, Monstera plants are invulnerable to pests. But let me assure you, over the past few years my Monstera fell prey to harmful pests, which can significantly damage its stunning aesthetics if you do not identify and address promptly.
Infestations of pests such as spider mites and thrips can lead to discoloration and the appearance of brown spots on your Monstera plant leaves. Another culprit, the weevil, is a chewing insect that can create unsightly holes in the plant’s foliage.
On top that, you might observe a flurry of fungus gnats buzzing around your Monstera’s pot. This damage can halt your Monstera’s vigorous growth, adding stress and making it more susceptible to further harm.
I’ve been growing Monstera plants for several years now, and throughout this time, I’ve encountered numerous insects and pests that target these beauties.
I will provide you with tips on how to identify them and methods to effectively eliminate them. Importantly, I’ll share techniques that have worked for me, enabling you to get rid of these pests without overly relying on harsh chemical treatments.
- 1- Thrips on Monstera
- 2- Spider Mites on Your Monstera Plant
- 3- Scale Insects on Your Monstera
- 3- Fungus Gnats in Monstera’s Soil
1- Thrips on Monstera
If you’ve been nurturing houseplants for some time, you might already know the hurdles they can face. One major issue comes from tiny critters that are just like miniature vampires, draining the vital sap from your plant’s leaves.
Not only do they cause unsightly brown spots, but they also weaken the plant, making it more susceptible to other diseases.
Recognizing the telltale signs of thrip damage on your monstera is crucial. The most obvious symptom is leaves developing light, almost whitish, guttate spots that gradually darken to a brown hue.
Moreover, the leaf surface may appear as though it’s covered in scabs, and new monstera shoots may exhibit curved or malformed leaves.
But there’s more to these tiny invaders than meets the eye. Surprisingly, these pests can sometimes carry a virus that causes mosaic disease.
This ailment mimics symptoms of nutrient deficiency in your monstera, leading to a loss of vibrant green color. Instead, the leaves of young monsteras turn light green or yellow. While this disease is uncommon, it can indeed be transmitted through thrips acting as carriers.
Identifying Thrips on Monstera
Spotting Thrips on Your Monstera Discovering thrips on your monstera leaves can be quite challenging. Their tiny size can easily evade a casual glance, making it crucial to know exactly what you’re seeking. Here’s a quick guide to help you identify these sneaky pests.
The color of thrips can vary greatly. From black, yellow to milky white, they aren’t the typical bugs you might expect. In fact, they often resemble dust particles or water spots on your monstera leaves.
Here’s a snapshot for your reference. But remember, their color can change, so don’t rely solely on this.
If you have a variegated monstera, spotting thrips might be even more of a challenge due to the plant’s patterned leaves. But don’t worry, there are ways to spot them.
If you notice any specks on your monstera leaves – black, yellow, or milky white – simply give them a gentle nudge with your fingernail.
If they start moving, you can be sure they’re not just specks but indeed thrips. As you gain more experience, you’ll find it easier to spot them at a glance.
Don’t have a magnifying glass handy? Here’s a quick trick you can use to identify thrips: snap a high-resolution photo with your smartphone and zoom in for a closer look.
This method can provide instant confirmation of whether those tiny specks are in fact thrips. The more you do it, the easier and quicker it will become to confirm their presence.
How to Get Rid of Thrips
Thrips are highly fertile creatures that multiply at an impressive speed from April to October when the weather is warm (68°F to 77°F or 20°C to 25°C) and dry. Because of this, you might find it challenging to keep thrips at bay from your beloved monstera plant.
Despite your best efforts in using insecticides or thoroughly rinsing the plant, they somehow manage to stage a comeback.
It’s essential to understand that thrips are highly resistant to insecticides and never truly enter a dormant phase—they merely wait for conditions to be right to multiply again.
This resilience can make controlling thrips somewhat challenging. But don’t worry! Here are some effective methods to help you eradicate thrips from your monstera, as well as other houseplants.
- If you notice any severely damaged or curled leaves on your infested monstera due to a thrips attack, you might want to prune these off. Your monstera won’t mind a bit of heavy pruning—it will bounce back with fresh, shiny leaves.
- Thrips are drawn to blue and yellow colors, so try placing blue or yellow sticky traps around your monstera. This strategy can effectively catch adult thrips and significantly reduce their rate of reproduction.
- I once found success in repelling thrips from my monstera by using heat shock. This method involves exposing the plant to high temperatures for short periods, which seems to suppress thrips activity and control their population. However, be aware that this can be a risky maneuver for your plant and may cause damage. To reduce the risk, I ensure my plant is well-hydrated before exposing it to a temperature of 107.6°F to 113°F (42°C to 45°C) for 5 to 10 minutes, 2-3 times a week.
- Thrips often hide on the underside of monstera leaves. If you spot any there, wipe the leaves with insecticidal soap or neem oil, and then give the plant a strong spray with a water hose. This approach helps remove both visible and hidden eggs and larvae.
- Some plant parents find that thrips infestations can reoccur even after using neem oil and insecticidal soap. This is because thrips are incredibly resistant to chemical insecticides. If this is your case, you could try using a different insecticidal soap spray to see if it has a more effective result. If you notice a decrease in infestation, continue using this treatment until you completely get rid of the thrips. Remember, persistence is key in dealing with these persistent pests.
2- Spider Mites on Your Monstera Plant
Recently, I’ve spotted these minuscule pests creeping on the leaves of my indoor Monstera plant. Despite my best efforts, snapping a clear picture of these elusive critters proved to be a challenge due to their incredibly small size.
Resembling tiny beige specks, their intricate details, such as legs, are hard to decipher. But a closer look reveals their dynamic movements – a trait indicative of mites.
These invaders take on a red, spider-like form and are always on the move. A telltale sign of a spider mite infestation is the thin, web-like structures they weave for ease of navigation between various parts of your Monstera.
As they feed on the leaf chlorophyll, you’ll start to notice white spots or specks, particularly on the leaf underside – their preferred feeding grounds.
This consistent nibbling leads to the emergence of white or yellow stripes on your Monstera, giving the leaves a sunburnt appearance and eventually causing them to wilt and die off.
Rest assured, these signs are not indicative of sunburn, especially if, like mine, your plant is placed indoors, away from direct sunlight.
I tried to get rid of these pests by vacuuming them and wiping the leaves with a damp cloth. But to my dismay, they reappeared the next day, in even greater numbers. If left unchecked, these mites have the potential to multiply rapidly.
Eliminating Spider Mites from Your Monstera
My first line of defense involved using mite-specific insecticides, which appeared to provide a temporary solution. However, these pesky creatures would bounce back in a few days, or sometimes even as soon as the day after treatment.
Interestingly, spider mites aren’t fans of water, so one efficient method to curb their population involves submerging your Monstera in water. Of course, this method is more feasible if your plant is on the smaller side.
If you’re constrained by space or prefer not to use your bathtub for plant-washing, rinsing the leaves, particularly the underside, with water is also an effective method. A wipe-down with isopropyl alcohol or plain water using a clean cloth also helps to eliminate any stubborn mites.
Remember, if your Monstera is densely foliaged, consider pruning to increase ventilation and minimize the risk of re-infestation.
My personal favorite is a biophysical approach – introducing predatory bugs like Persimilis (Phytoseiulus persimilis) into the plant ecosystem. These harmless creatures feed on spider mites and their eggs, effectively controlling their population.
It may take some patience to see noticeable results, but trust me, it’s worth the wait. Your local garden store should stock a variety of these friendly predators, but availability may vary based on the local climate and environment.
Remember, spider mites are not isolated threats. If they’ve infested one of your plants, they’re likely to move onto the others. It’s crucial to control their population to protect your entire indoor garden.
And the best part about the biological control method? It’s safe for your plants, children, and pets.
3- Scale Insects on Your Monstera
Scale insects can pose a major threat to your Monstera plant. These little pests not only damage the plant by draining its leaf sap, but they also promote the growth of a fungal disease known as sooty mold.
Insects like scales, mealybugs, and aphids release a sugary, sticky substance after consuming the leaf sap. This substance not only attracts other pests such as ants, but also encourages the development of the dreaded sooty mold.
If this sticky substance isn’t promptly removed from the leaves and trunk, sooty mold can proliferate, causing a nasty black sooty mold disease. This mold feeds on the excrement of scale insects – a chilling thought! So, it’s best to be vigilant.
How to Eliminate Scale Insects from Your Monstera
While performing a routine check of my Monstera plant, I noticed the leaf surfaces looked clean and healthy. However, upon inspecting the undersides, I found a brown bug, easily visible if you look closely. This tiny invader was approximately 0.04 inches (1mm) in length.
I was initially alarmed, but thankfully, I could easily remove it with a damp tissue. I spotted a few more on the undersides of other leaves and swiftly wiped them away as well.
To make the task easier, consider utilizing a few tricks before applying insecticides to control the scale insects. From May to July, scale insects are in their larval stage, making insecticides most effective during this period. However, the situation can become complicated once they mature.
The effect of the insecticide diminishes by half when they become adults. In such cases, manual removal can be highly effective. I recommend using an old toothbrush to brush off the easily identifiable pests from your Monstera leaves.
A few days later, while watering my Monstera, I recalled the scale insect infestation. After carefully examining the undersides of the leaves, I found no trace of the pests. I was thrilled – it felt like a victory.
However, as I watered the base of the plant, I noticed movement. To my dismay, the base of the plant was crawling with scale insects!
The few I had found on the leaves had merely been a distraction; these pests had been congregating at the base of my Monstera all along, ready to infest the entire plant.
Frustrated, I spent an hour meticulously removing the scale insects using a cotton swab dipped in alcohol. The alcohol content dissolves the hard shell of the scale insects, making them easier to remove.
Despite the annoyance, I found the removal process oddly satisfying. That day, I believe I rid my plant of over 100 scale insects.
What I’ve Learned About Dealing with Scale Insects
I’ve realized that you can’t simply rely on pesticides like horticultural oil or insecticidal soap to eradicate scale insects from your Monstera. These treatments are only effective when the insects are in their larval stage.
As the insects mature, their shells stabilize and become harder, which reduces the impact of the insecticides. It’s as though they develop a resistance against these treatments.
Hence, the best approach is to visually locate and remove them using a cotton swab or brush them off with a toothbrush. I’ve also found baby wipes to be quite effective.
Furthermore, these insects are vulnerable to water, so spraying them off with a hose can also be a very effective strategy.
3- Fungus Gnats in Monstera’s Soil
There’s nothing worse than seeing flies buzzing around my beloved Monstera plant. There’s a chance you’re dealing with fungus gnat.
Apart from the tiny bugs that tend to pop up this season, it’s the smell of decay that gnats find irresistible. They’re attracted to areas rich in nutrients, like the corners of your kitchen or the fertile soil of your Monstera plant.
How to Get Rid of Fungus Gnats
Another method to reduce the population is by removing and replacing the top layer of your monstera soil, roughly 0.8 to 1.2 inches (2-3 cm).
For potted plants, adding decorative stones or bark chips on top of the soil can help prevent these gnats from laying their eggs, effectively controlling the infestation.
You’ll notice a significant reduction. Also, it’s essential to keep the area well-ventilated and not overly damp. A high probability of gnats breeding exists in poorly ventilated, damp areas—much like your typical kitchen corner.
If you want to change the soil, consider using Organic Potting Soil. This is a quicker solution than trying to devise your own mixture. However, keep in mind that soil and bugs have an inseparable relationship—it wouldn’t be surprising if the gnats returned.
When dealing with fungus gnats, it’s best to use the yellow sticky traps. These gnats lay their eggs on the soil’s surface, so the adhesive can effectively trap them. Rest assured, these adhesives don’t contain any chemical insecticides.
If you’re looking for a more comprehensive solution, there are also spray-type agents that can wipe out Black Fungus Gnats.
This can be particularly helpful for those of you growing a variety of flowers and foliage plants or those dealing with other pest problems. The spray-type option might be the most convenient for you.
- Monstera plants, prone to pest attacks, suffer aesthetics and health impacts from thrips, spider mites, scale insects, and fungus gnats.
- Thrips drain Monstera leaf sap causing brown spots and weakness, and they are detected using a magnifying glass or high-resolution photos, with removal methods including pruning, sticky traps, heat shock, and persistent use of insecticidal soap or neem oil.
- Spider mites feed on leaf chlorophyll, causing white or yellow stripes, and they can be controlled by rinsing leaves with water, wiping with isopropyl alcohol, or introducing predatory bugs like Persimilis.
- Scale insects drain leaf sap and promote sooty mold, but manual removal or a cotton swab dipped in alcohol can dissolve their hard shell for easier extraction.
- Fungus gnats target fertile soil, so removal of the topsoil layer and ensuring well-ventilated, less damp conditions can help control their infestation.