I know it is very annoying when you suddenly see white dots moving on the leaves of your prized Monstera plant. The little white dots are actually thrips.
A new thrips infestation can be treated with sticky traps or a lint roller, but more persistent infestations will require you to remove infected parts and use insecticidal soap or form a beneficial relationship with ladybugs.
In this article, I will explore the signs of thrip infestation, how to control them, and ways to prevent these tiny winged pests from inhabiting your plants.
Let’s get started!
Things you Should Know About Thrips
How do Thrips look like?
Thrips are small, thin (usually) winged bugs that resemble rice to the naked eye. These insects are tiny, measuring between 1.5-3mm in length.
There are 6,000 different species of thrips. Most commonly found in Monstera plants are yellow or black.
How Thrips damaged Monstera leaves?
Before laying eggs, adult female thrips will make a hole in the plant’s tissue. Several days later, the nymphs will hatch and immediately begin to feed on the sap.
Without these sap, Monstera could not transport water and nutrients effectively throughout the plant.
Thrips Life Cycle
The nymph undergoes two more nymphal stages before dropping to the soil to pupate and turn into an adult thrips.
During the hotter seasons, it takes up to 12 days to complete this process. However, during winter the process slows down and can take 40 days.
Thrips thrive in warm temperatures, ideally between 80 and 85° Fahrenheit (27 – 30° Celsius). However, they can remain active in temperatures as low as 50°F (10°C) and as hot as 90°F (32°C).
On average, thrips live for about 45 days. But they can also produce up to 15 generations in one life cycle.
How to Identify Thrips Infestation on Monstera
Thrips will suck the life out of your Swiss Cheese plant, so keep an eye out for when your Monstera starts to look lifeless as this might be a sign of an infestation.
There are several methods of identifying signs of thrips on your monstera plant:
- Look for yellow or brown discoloration on the leaves
- Check if there are black spots on the underside of any leaves (this is excrement)
- Look for wilting or droopy, curling leaves
- Use a magnifying glass to look for thrips crawling on the surface or underside of leaves
One creative method of confirming you have a thrips infestation is by shaking one of the Monstera’s leaves over a sheet of white paper. This will make the thrips easier to see with the naked eye.
How to Save Your Monstera Plant from a Thrips Infestation
Now that you’ve confirmed that your Monstera plant is infested with thrips, there are several steps you can take to save it. These include:
- Luring them with a blue (or yellow) sticky trap
- Physically removing the thrips by wiping them away with a lint roller
- Using insecticidal soap
- Releasing ladybugs to help rid the thrips
- Pruning the damaged leaves
- Propagating surviving leaves (only if you couldn’t save the entire plant)
Luring Thrips with Blue Sticky Bug Traps
Plant parents may also use blue sticky traps to lure the bugs away from their Monstera. Thrips are attracted to the colors white, yellow, and blue.
You can buy insect traps online and in stores. Alternatively, you can also make one with the items you already have lying around your house.
How to Make a Homemade Sticky Bug Trap:
Sticky bug traps are an easy and efficient method of removing thrips infestation. To make a homemade sticky bug trap, you’ll need to use:
- A white or blue index card or piece of paper
- Honey, non-stick glue, or Vaseline
Place the sticky substance on your colored sheet of paper and place it in your planter; the thrips will be attracted to the color and walk right onto it.
Removing Thrips with a Lint Roller
Using a lint roller is a practical tip from a friend of mine, which works well to remove thrips. Lint rollers work similarly to sticky traps.
Carefully hold your Monstera leaf and glide the lint roller across the leaf’s surface; the thrips will get attached to the adhesive for easy physical removal.
Use Insecticidal Soap to Kill Thrips
Insecticidal soap, also known as horticultural soap, is made up of potassium fatty acids. When used, it will break down the bug’s outer shell on contact. This causes the thrips to become dehydrated and die.
Since insecticidal soap is water-based, it dries quickly. Once it is dry, it will have no effect on the thrips.
To use insecticidal soap on your Monstera plant:
- Shake the bottle of insecticidal soap well before spraying
- Spray a small amount of soap on an inconspicuous part of your Monstera to see if it works. Check your Monstera plant in 24 hours; if you see brown spots known as scorching, dilute the insecticidal soap by half and try again.
- Spray the stem, surface, and underside of leaves thoroughly.
- Repeat this process every other day for two weeks until the thrips infestation is gone
If this is your first time using insecticidal soap to remove thrips from your Monstera, we have a few tips:
- Spray the plant before 9:00 am or after 5:00 pm to help prevent the insecticidal soap from drying out quickly due to the heat.
- Make sure your Monstera has been watered before spraying
How to Make Your Own Insecticidal Soap
If you prefer to make your own insecticidal soap, it’s easy to create with items you already have in your home.
What You Need:
- A clean spray bottle
- All-natural soap
- Pure water (tap water is also safe to use)
Step 1: Determine How Much You Need
The amount of all-natural soap you’ll add to the water, depends on how much product you want.
If you want a gallon of insecticidal soap, you’ll add 4-5 tablespoons of soap to the water. If you want a quart, you’ll only mix 1 tablespoon of soap.
Step 2: Mix Together
Mix the all-natural soap with the water. You’ll want to mix these together thoroughly before spraying.
Step 3: Spray Immediately
As soon as you are done mixing your insecticidal soap, you should spray your plant immediately.
Step 4: Repeat the Process
Experts recommend repeating this cycle every 4-7 days, as needed until the infestation is gone.
Releasing ladybugs onto your Monstera plant is an eco-friendly method of getting rid of a thrips infestation.
Ladybugs are natural predators of thrips and they will feast on the eggs and larvae before they become adults. This helps with population control. You can order adult ladybugs online at popular hardware stores like Home Depot and Lowe’s.
Pruning Damaged Monstera Leaves
Once thrips have been removed from your Monstera plant, you may notice a few damaged leaves which should be pruned. This will provide the means for your Monstera to support new growth.
What You Need to Get Started:
- Pruning shears (or a knife, if you don’t have any)
How to Properly Prune Your Monstera Plant
Step 1: Put Gloves On
Monstera sap can be irritating to sensitive skin. Protect yourself with gloves to reduce the risk of rash or infection.
Step 2: Identify Where You Want to Cut
You’ll want to look for yellow, black, or brown spots on the stems and leaves of your plant. Use yarn or string to mark these areas so you know where to cut them off with shears.
Step 3: Remove Damaged Leaves
If you want to remove damaged foliage entirely, make a flat cut across the stem as close to the parent node as possible. If you are only removing the infected section of the leaf, use shears to carefully cut around it.
Propagate Surviving Leaves
If you were unable to save your Monstera plant, the last option is to propagate the surviving leaves. Propagation is the process of creating new plants from a single leaf or leaf cuttings.
How to Propagate Your Monstera Plant
Propagating your Monstera plant is a simple and fast way to create new growth.
Step 1: Find the Node
A node is a brown, circular-shaped ring on the stem of where a leaf used to be. These nodes are crucial to propagating your Monstera because each node can support new leaf growth.
Step 2: Cut the Stem
Make a clean cut of the stem that includes the node. Immediately wash this stem after removing it from the plant
Step 3: Put in Water
After washing it, place the stem in a jar of room temperature water. Monstera plants thrive in temperatures between 68-86 degrees Fahrenheit. Make sure the water covers the plant’s roots when you go to put it into a container.
Step 4: Position the Stems Upright
Monstera plants are climbers, which means they enjoy indirect sunlight and medium to bright environments. To reproduce this environment indoors, you can use a taller vase or jar as well as a twist tie so your plant stays upright.
Step 5: Change the Water Every Couple of Days
Change the water in the pot every 3 -5 days to keep it fresh. New roots will begin to appear within 2-3 weeks!
Step 6: Plant in Soil
You should be able to pot your plant one month after it is propagated. Look to make sure they are at least two inches long before planting to fresh soil.
Preventative Measures for Thrips Infestation
There are several things you can do to help protect your Monstera plant from succumbing to another thrips infestation. These include:
- Isolating new plants
- Regularly cleaning the leaves
- Maintaining the leaves with Neem oil
- Removing weeds on the soil
Isolating New Plants
To prevent a thrips infestation from spreading to your other plants in the house, isolate newly purchased plants by keeping them away from your existing plant collections.
If you purchase a new plant, isolate it for 30 days in order to check for any common pests or disease problems.
Clean the Leaves Regularly
Dirty leaves are an easy point of entry for bugs like thrips or even spider mites and fungus gnats. Cleaning your Monstera plant every week can help keep these annoying houseplant pests away.
You can control thrips by wiping off dirt, dust, and particles from leaves using a clean, damp cloth.
Maintain Your Monstera Plant with Neem Oil
Neem oil is a natural pesticide that, when used in moderation, does not harm plants but can suffocate and repel insects.
How to Apply Neem Oil to Your Monstera
- Combine 1.5 teaspoons of neem oil with 1 liter of lukewarm water and 1 teaspoon of liquid soap in a spray bottle and shake
- Test a small amount on a leaf to ensure there is no damage. Check back in 24 hours.
- If there’s no damage, generously spray on the surface and undersides of leaves, including the stem
- Put the plant in a shaded area away from sunlight until the neem oil dries
Things to Remember About Neem Oil
Neem oil has a very strong odor similar to garlic, however, this goes away after the oil dries.
It’s also important to spray neem oil when thrips will be most active, usually in the early morning hours or in the evening.
Do not oversaturate your Monstera plant with Neem oil, as this will kill it. Neem oil lasts on a Monstera plant for about 1-2 days.
Remove Weeds on Soil
Weeds provide a welcoming environment for thrips, offering food, shelter and places to hide.
The unfortunate thing about weeds is that they can pretty much grow and survive anywhere – including your Monstera plant.
After removing the weeds from your Monstera plant, it’s recommended that you use a 20-20 liquid fertilizer. This is an all-purpose fertilizer and plant food that will help keep your Monstera plant healthy.
A healthy plant is the most efficient way of making sure your Monstera doesn’t fall victim to weeds or a thrips infestation.