White spots on indoor plants are issues that could happen due to different reasons and would also be different factors that are behind them. However, there are other causes and problems than just the room you keep your plants in.

White Spots on Indoor Plants

If you’ve spotted these strange white patterns, you’re probably wondering about the causes. This article is here to help you find out what’s troubling your houseplant, as well as how to treat the causes of these white clumps.

What Are The Causes of Indoor Plants to Develop White Spots?

The causes of indoor plants developing white spots are powdery mildew, downy mildew, and aphid attack. It could also be the result of mealy bugs, and spider mites; on the flip side, it may also be due to nutrient remnants.

There are many causes of those spots on your plants, and while some may be directly caused by indoor conditions, others are caused by insects that will suck the life out of those leaves. A close-up inspection of your plants will often solve this conundrum.

– Powdery Mildew

Powdery mildew is probably the most common fungal disease and almost all plant world is susceptible to it. This issue can develop as white mold or powdery clumps on the top of the leaves of your plants and the best way to tell if you have it is to run your fingers through it.

If the substance leaves a white powdery smudge then powdery mildew is your culprit. Luckily enough this disease isn’t deadly to your plants and is treatable with high success. This means that you can reverse it, slowly but surely take care of it, and reduce the issue from your house plants.

– Downy Mildew

This one is often confused with powdery mildew because the symptoms are somewhat the same. However, the powdery disease affects the top sides of the plant leaves, while downy mildew affects the bottom sides and occurs in spring and fall months when there’s plenty of moisture and not enough air circulation in the home.

The white spots caused by this disease will quickly go black and brown and gray on the edges. The excess humidity would cause the plant to show these issues, and it could be different environmental factors that would harm the plant’s exterior.

– Aphids Attack

If the white spots on your plant’s leaves are moving, then you’re likely dealing with an insect infestation, and the most common of these are aphids. Aphids are small white and translucent, pear-shaped insects, and these will often group and look like white soot on plant leaves. On the same notion, you could also see them looking white in the center and quite darker on the edges.

However, if you take a closer look you will see them quickly pacing around looking for a perfect spot to latch onto and suck the sap of your indoor plant. After they cling to the leaves they will appear dormant, and it’s at this stage that they’re most vulnerable.

Causes of Indoor Plants to Develop White Spots

As soon as they mature from enough food, you will have another thing coming and will likely have to take much of your foliage down, and this is how they will develop.

– Mealybugs

Just like aphids, these are tiny insects that infest and eat off your plants. The mealy bugs are ones that are often mistaken for white flies as both insects produce a white substance which places them on this list. However, mealybugs are wingless and will stay on your plants for longer periods, as they would come and stick to the plant.

Other than feeding on plant sap they will often cause stunted growth and can distort younger freshly forming leaves. It’s because they feed off the plants so aggressively, and they would show the dots so obviously. These bugs will most often be found on stems and leaves, but if you’re dealing with serious infestation they’ll attack your potting mix as well and eat away at your roots too.

– Spider Mites

Along with aphids, these will be the most common creatures attacking your plants. Spider mites are the tiniest and barely visible insects that can attack your plants, but coincidentally the ones that do the most damage. They would also increase their growth and develop faster if they feed on the nutrients and grow even more.

They can often be found on the undersides of foliage and leaves where they will weave protective silky webs to protect their bodies when feeding off your plant. Spider mites come in many different colors most commonly red, green, and yellow. On the same note, it is when they weave their webs is when they will become most evident as white colonies of tiny moving creatures.

In colder climates, these will overwinter in eggs and mature in just a few weeks come springtime, so they’re a tough nuisance to get rid of. You should inspect your plants regularly for signs of their activity, for instance, fine webbing is a clear indication of this, which means that if you spot it, look on the underside of the leaves, and you may just discover those red points going about.

– Nutrient Remnants

A lot of fertilizers for your house plants will either come in hard or liquid form. No matter what these may occur in they will likely be some amount of salt in them, and this would also be due to the minerals that are rich in salt.

If you’re aggressively feeding your plants without following the schedule prescribed on the label, salts may accumulate. At first, they will accumulate in the soil where your fertilizers were applied choking the roots.

On the other hand, if you’ve gone overboard with fertilization these salts may through evaporation climb to the canopy and stems of your plants, causing further problems and appearing as white spots. If you’ve done your feedings properly, and you’re still seeing salt crystals forming on your plants, these might’ve come from the water, so you’ll likely need to purify your water for the next watering session.

What Are The Treatments of White Spots on Your Indoor Plants?

The treatment of white spots on your indoor plants could be pruning the damaged leaves, or you may also spray some homemade solution. You can also spray some insecticides, or try to isolate the plant and repot it, and lastly, try to brush off the soil.

To know what is possibly going on with those white things on indoor plants’ leaves, we can approach treatment far better. Recognizing the root cause will help you reach a solution far better than just doing anything you can topsy-turvy, doing even more damage to the plant.

– Pruning the Damaged Leaves

We already mentioned that mildew isn’t that harmful of a disease. But it surely doesn’t look too attractive either, so to begin treating it you should first remove any infected foliage. After removing the foliage it’s time to treat the plant with some fungicide so that the new foliage would be growing at a stronger pace, where the new leaves will be growing strongly.

– Spray Some Homemade Solution

The best thing to go with here is some homemade remedy, mix up to two or three tablespoons of baking soda in a gallon of water and spray and rub it in the plant. This is an effective fungicide that will help your plant back to health, and since your plants are indoors, you can move your plant into quarantine for a few weeks, just to make sure the disease is gone, and no other plants will get infected.

Treatments of White Spots on Indoor Plants

You should look to grow your green friends in somewhat drier spots with good air circulation to prevent powdery mildew from forming. You may also open the window every other day to get some fresh air inside so that the environment will be cleaner.

– Spray Some Fungicides

Getting rid of aphids shouldn’t include any nasty chemicals, because they can spoil the plant as well. When you can reach for the homemade solution here as well — use neem oil and mix it with water. Neem oil is an effective fungicide that will suffocate and kill all of the aphids hanging on your leaves.

For even more protection you can use a mixture of hand soap, rubbing alcohol, and water which you can then rub on the leaves with a cloth to make sure that the environment is no longer attractive to aphids. In short, these will be the ones that will protect your plant, and they will be in a way a barrier to not letting the pests in, and harming your plant any longer.

– Isolate and Repot

Mealybugs and spider mites are far worse than aphids, as these can penetrate the potting soil as well. To treat the plants when they’re infested by these, you should first isolate plants and do the same treatment as you did with aphids.

However, if you’ve spotted some of the insects moving around in the dirt, you should think about potting your plants in a fresh soil mix. Which means that you can repot the plant and begin with a fresh start

– Brush Off the Soil

Removing salty deposits and nutrients remaining you can brush them off with some distilled water and an old toothbrush. A more gentle option is to place your plants in an area with high humidity for a while — the bathroom being a perfect option.

Shower steams will evaporate salt crystals into the air; however, they can again cause issues with mildew or other fungal diseases. Another worthy option is to spray some distilled water onto the plant and scrub away with a softer cloth, which will be more tedious but less harmful than a toothbrush scrub.

Spray Some Fungicides on Indoor Plants


We all love growing those wonderful indoor plants as they make our lives and rooms happier and more lively. However, they do with their own set of issues, most notably, stale air and air humidity in our living rooms. Here is what we covered in this article:

  • Humid air conditions can lead to diseases and fungal issues like mildews forming. These won’t be harmful but will remind us to look after our plants better.
  • Sap-sucking insects are far worse a sight when it comes to those spots, as these are live targets that we won’t get rid of that easily.
  • Insecticides aren’t a great option to be used indoors, so prevention is your best option.
  • Always try to keep your plants in a place where you can ensure some circulation of air for a few hours a day.
  • People often jump to conclusions and think that the culprit is powdery mildew, but it is not always the case, because it could result in other aspects as well.

Now that your plant care routine includes know-how about handling white spots on those plants, we’re sure they’ll be growing happily ever after.

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