Last Updated on April 15, 2022 by Admin
Spider mites on Calathea can happen any time. You wake up one day and suddenly notice thin webbings on your plant.
What should you do? And how can you confirm that spider mites are in fact the problem?
In this article, I’ll go in depth about spider mites on calathea plants including the symptoms, how to identify them and treatment.
How do you get rid of spider mites on Calathea? Neem oil or insecticidal soap are very effective ways to getting rid of spider mites from Calathea plants. But you need to make sure you know how to use them since too much can damage the leaves in the process.
What are Spider Mites?
Spider mites are kind of like miniature spiders. They get their name from the webbings they spin.
Like other houseplant pests, these are tiny bugs that are hard to spot with the naked eye until they’ve grown in number.
This is why the leaf damage, webbings and other symptoms are what you usually notice first with these plants.
They like to hide on the undersides of leaves. So, it is very important to check each leaf on its back side for any signs including eggs, adults and larvae.
Spider mites have a 5 stage life cycle. Each bug has a short lifespan of between 5 to 20 days as well. As such, you’ll see spider mites either as:
- Nymph (there are 2 stages here)
When treating spider mites, it is very important to get rid of all of these.
Leaving one will allow the cycle to start over and repeat reproduction within a few days.
Because spider mites have short lifespans and they will breed and lay eggs before they die, their population grows quickly.
Additionally, each female can lay over 100 eggs.
This allows them to multiply very quickly. Therefore, don’t wait to treat the plant when you see just a few bugs present.
What Do Spider Mites Look Like?
Why Does My Plant Have Pests?
Unfortunately, pests are a normal part of plant life.
Most houseplants have natural resistance and defenses to pests like spider mites. Although, some are more prone than others.
Also, they different pests choose the plants they like.
This depends on the plant’s features.
For examples, pests like plants with large, thick leaves. Additionally, they prefer the sweeter taste of younger leaves.
Again, this can vary.
The problem is, your Calathea can become more susceptible to spider mites and other pests when it is stressed, in shock, weak or sick. That’s when its natural resistance is down.
Additionally, dust on the leaves makes plants attractive to the pests since they like dust and dirt.
So, keeping your plant healthy and cleaning it regular help a lot.
That said, there are other environmental factors. Some bugs like high humidity while others come during the warmer months.
Where Do Spider Mites Come From?
Spider mites are commonly found in subtropical regions as they like temperature climates.
For most houseplants, spider mites usually follow you home via the plant when you take it home from the nursery, garden center or plant store.
In these locations, there are lots of plants being grown at the same time.
And they’ll usually have some garden space open to the public to pick out their plants.
In many cases, the plant you bring home may already have pests. As such, I always recommend putting any new plant, whether you get it from a store, an exchange or as a gift from friends, on quarantine.
Leaving just outside your home or in an area away from all your other houseplants for 2 weeks work really well.
This will let you monitor the plant for any issues.
And if there are pests or diseases you’ll be able to notice them within those 2 weeks. This way, by the time you move them in with your collection, you’re sure they don’t have any issues.
Another common cause of spider mites in houseplants is when you bring your plant in from the garden.
Many home gardeners will take their plants outdoors and give them some sunlight especially during the warm weather months.
But at some point they’ll bring them indoors again, usually as the weather gets cold in fall.
Since your garden or backyard is teeming with insects and bugs, you always need to clean and debut each plant and its pot before bringing them indoors from your yard.
Otherwise, the pests can hitch a ride with the plant and infect the rest of your houseplants.
Finally, there’s you.
Spider mites can come in via open windows or doors that are right beside your yard or garden. They can also take a rid on your shoes, potting mix you’ve previously used, clothes or pets that just played in the yard.
How Do Spider Mites Damage Calathea?
Spider mites are sap sucking insects. Basically, they feed on Calathea plants by sucking its internal juices.
Sap contains moisture and nutrients that the plant absorbs from the soil. And it is distributed to the leaves and the rest of the plant to nourish these parts.
Spider mites have mouths that will piece through the plant’s outer tissues. They will then suck the sap juices out of the Calathea’s leaves.
This is why the leaves will sustain damage in the form of spots, holes and other abnormal patches.
Unfortunately, as the number of spider mites increase (and they do very quickly), they’ll rob more and more of the plant’s moisture and nutrients.
As a result, the leaves will turn yellow and wilt later on.
After a while, this also weakens the plant since it will start to lack water and experience nutrient deficiencies.
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Signs of Spider Mite Infestation on Calathea
Now that you have a good background of what spider mites are and why they can be dangerous to your Calathea, it is time to learn the symptoms of Spider Mites infection on Calathea plants.
This way you know what to look for and once you see these signs, are aware of what’s happening.
Discolored and Droopy Leaves
One of the most noticeable things that will happen to your Calathea plant once it is infected by spider mites is it will droop.
Although, a more unique symptom are the small, yellow dots on the surface of the leaves. These stippling makes the discoloration quite obvious as they’re lighter compared to the natural, healthy foliage color.
To make sure, always use a magnifying glass when inspecting your plants for pests.
That’s because these are very tiny creatures.
And to confirm which pest is there, you’ll want to see them with your own eyes.
The most telling sign that your Calathea has spider mites are the webbings.
This is a unique feature of spider mites and it is where the bugs get their names.
Spider mites will weave small, thin webbings that are visible on the stems and on the undersides of the leaves of the plant. These protect it from predators.
Your Calathea Leaves Don’t Close at Night
Calathea are part of the prayer plant family because their leaves open and close.
At night, they will close their leaves and taka a prayer-like position. It does this to conserve energy since there isn’t a lot of light to collect after nightfall.
Once dawn arrives, the leaves will open back up as it knows there’s a full day of sun available.
When there are issues with your Calathea or there’s too much light in the evenings, the leaves won’t close at night.
And pest infestations cause this to happen as well.
It happens because bugs like Spider mites feed on the plant’s sap which affects is natural day and night cycle.
How to Get Rid of Spider Mites on Calathea Plants
Of course, the most important part of this article is knowing how to get rid of spider mites in Calathea plants.
However, you’ll notice as I go through the different options and solutions that they are pretty much straightforward.
This actually makes getting rid of spider mites easy.
He actual hard part when dealing with these pests happen in the sections above. That is, you need to identify and confirm that it is actually spider mites infecting your Calathea plant.
Additionally, an essential part is discovering the pests early since they’re much more difficult to get rid of when they turn into an infestation.
Thus, early detection, proper identification are actually the harder and more important aspects.
The solution is more mechanical.
Below, I’ll go through the steps that will have you save your Calathea from spider mites and get rid of these pests from your plant.
Isolate the Infected Plant
The first thing you always need to do if you suspect or notice a pest or disease infection is to isolate the plant.
Keep it away from all your other houseplants because both bugs and infections will spread.
In addition, make sure to check the nearby plants to make sure they haven’t already been infected. Spider mites, along with other insects can easily travel or “jump” to other plants.
Move any and all the plants that have been infected and quarantine them.
This will let you treat them while keeping the other plants safe.
Remove Any Affected Leaves
Take a pair of scissors or pruning shears then sterilize it with rubbing alcohol or hydrogen peroxide.
Then cut off any leaves that have damages including spots, holes, dying or dead ones. These have been fed on by spider mites. And there may still be eggs or larvae hidden behind the leaves or around it.
Pruning the leaves and other affected areas will help get rid of some of the bugs.
But remember, these keep reproducing thanks to their ability to lay a lot of eggs at one time and their short life cycles.
So, you need to get rid of all the adults, larvae and eggs.
Otherwise, leaving any one of them will cause the cycle to start repeating after a few days.
Make sure to throw away the affected leaves. Don’t just dump them but carefully dispose of them separated.
Clean the Stems and Leaves with a Damp Cloth
Use a soap solution to wipe the stems and leaves. This helps remove some of the spider mites from your calathea.
And since coming into contact with liquid soap will harm them, it helps keep them away for a while.
Just combine one teaspoon liquid soap with one quart of water. Mix well. I like to use castile soap. Although Joy dishwashing liquid works well too.
Then wipe the plant down with a damp cloth. Make sure to be thorough especially on the undersides of each leaf and the crevices of the stems and petioles.
These are where spider mites like to hide.
Use Insecticidal Soap
Insecticidal soap is one of the staples for getting rid of pests. And it doesn’t only work for spider mites but also common houseplant pests.
This works great because it is inexpensive and very effective.
Insecticidal soap damages the outer protective layer of the spider mites causing them to suffocate. Once this happens, they will quickly die.
But the hard part is that you need the soap to come into contact with the bugs.
As such, creating a spray is the most effective way.
You can buy insecticidal soap sprays that come in ready-made bottles. However, most home gardeners will just make their own spray since it is easy to do.
And it comes out cheaper. So, I do recommend trying this out.
Just mix one teaspoon of mild liquid soap with one quart of water. Dishwashing liquid usually will work. But I prefer to use liquid Castile soap.
Castile soap does not have any fragrances or additives added to it. More importantly, it has fatty acids that are more effective at destroying and dissolving the outer protective exoskeleton of spider mites.
Make sure to use the mixture above and not just to use fully concentrated liquid soap.
It has to be diluted considerably. Otherwise it will damage your Calathea’s leaves as well.
Therefore, always test the spray by applying on two or three leaves. Only spray on small portions. Then leave it for 24 hours.
The next day, check to see if the leaves are okay.
If there’s any browning or damage, don’t use the mixture. Instead, dilute the recipe even more with water or use a commercial pre-made spray.
If you immediately spray the entire plant with too much concentration, it could end up all brown within a few days then wilt, drop leaves and die.
So, always check.
If there are no side effects from the spray after 24 hours. That’s your go signal to use it.
To get rid of spider mites, spray your Calathea once every 4 to 6 days. Don’t do so daily. Make sure you get both the top and undersides of the leaves.
I like to spray in the mornings although you can do so later in the day as well.
Rinse the plant a few hours later to get rid of the dead spider mites.
Depending on how bad the infestation is, you may only need to apply a few times. Or it may require several weeks before the problem resolves.
Therefore, spotting the pest problem early is very important to shorten treatment duration.
Use Neem Oil (But Be Careful)
Neem oil is another option you can use instead of insecticidal soap. It is a natural and organic houseplant pest remedy.
That’s because it is a fungicide, insecticide and miticide.
It works by disrupting the insect’s hormonal functions which affects their ability to reproduce. It also causes them to stop feeding. As such, they die over time and don’t spread.
However, from my experience, there are two things to consider here.
- One is neem oil takes longer than insecticidal soap to work.
- Second, it is more dangerous than insecticidal soap because it is more potent. Therefore, you need to make sure you dilute the neem oil enough when applying it to your Calathea.
The second item is very important because overly concentrated neem oil can damage a lot of the leaves turning them from green to yellow within weeks.
At worst, they will change the leaf color, then after a while the plant will start wilting. Eventually, it dies.
I know because I’ve had a couple of plants this has happened to when I first started neem oil.
So, make sure you dilute it enough.
That said neem oil comes in pre-mixed spray bottles and concentrated containers.
If you’re not sure, go with the pre-mixed. They cost more. But they’re already diluted enough to make them safe for your plant.
On the other hand, the concentrated jugs are 100% neem oil. So, you need to dilute them with water.
Also don’t inhale neem oil since it can irritate humans. If you have sensitive skin, use gloves when handling concentrated neem oil as well.
If you decide to go with the concentrated neem oil, mix:
- 2 tablespoons (1 ounce) of neem oil
- 1 gallon of water
Make sure to mix well and put it in a spray bottle.
If you don’t need a much, you can scale it down like this:
- Half a tablespoon of neem oil (this is about a quarter of an ounce)
- 1 quart of water
Then spray the leaves both on the top and undersides.
Make sure to keep the plant out of direct sunlight until the leaves have completely dried from the neem oil.
Neem oil is phototoxic. Therefore, the leaves will easily burn or turn yellow if you leave the plant in too much light when the neem oil is applied.
Once a week application of neem oil for heavier infestations. For less serious cases, once every 14 days works well.
A few hours later, rinse the plant to remove any dead mites.