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How to Treat White Specks on Plants [Easy Methods]

Do not neglect your plants during the summer month, as the risk of white specks is highest due to humid and warmer conditions.

Generally, the white specks are the symptom of pesky diseases like powdery mildew and rust. Still, high temperatures, humid conditions, moist soil, pests like spider mites, and too much direct light can also initiate the white spot.

Too high or too low environmental factors can turn deadly to your plants. So scroll down to know all the responsible causes and control measures to apply.

What Causes White Specks on Plants?

Balancing the indoor environment is easier than the outdoors, as the rooms act as enclosed spaces to control the external surroundings.

However, things might go awry in the lack of proper care and maintenance, giving rise to powdery mildew that gives the leaves a cake frost appearance.

But do check if the white spot is due to environmental factors because if you have recently painted your home, chances are that the dots are just a paint or a stain.

Also, sometimes the plant tends to be variegated, so consult the seller, whether the plant is a hybrid or crossbred, as it is normal for them to have white spots.

If not, look at the given inducing factors that promote fungus growth.

1. Fungal Diseases

The primary reason for the white specks is a fungus called Powdery mildew that tends to affect various plants.

Starting from a single plant as white powdery spots, the fungi proliferate rapidly and transmit to the other plant in the space through the wind only.

However, the spread could also be due to the spores that remained dormant in the vegetative material in the past.

Most commonly, Roses, Tomatoes, Begonias, Ivy, Jade, Kalanchoe, and Poinsettia seem to have white specks due to powdery mildew.
Another on the list is the white spot disease caused by Mycosphaerella fragariae and white rust by Albugo candida which shows similar symptoms in the affected plants.
white spots on plants
White spots on plants are the sign of powdery mildew.

In addition, greyish-white hairs underside the leaf, commonly known as downy mildew, appears when the cool and damp conditions persist.

2. Mild to High Temperatures

Higher temperatures always favor dread as most fungi actively participate during hot days.

The powdery mildew strikes hard at 60ºF to 80ºF temperatures, spreading from a single spot to the entire leaves and fruits.

Even cold temperatures aided by shady places promote the growth of powdery mildew. In contrast, temperature above 90ºF slows down their spread.

However, that does not mean you should increase the temperature, as it can kill your plants.

3. Insufficient or Too Bright Light

Sunburn is common in low-light lovers, so keeping them in an east-facing or north-facing window has its trend.

However, low-light condition promotes moisture and higher humidity, the perfect surrounding for the fungus to grow.
The leaves of plants covered entirely with the powdery substance.
Low light condition favors more towards fungal growth more than excess bright light.

Meanwhile, changing the plant’s location to a south-facing window means higher intensity of light which leads to sunburn in the plants, another reason for the specks.

Also, direct rays of light increase the warmth of the space, promoting the optimal condition for fungus growth.

4. Pest Infestation

Beware of the little buggers like mealybugs, scale, spider mites, and aphids that leave a white powdery and web-like substance to show their presence.

To know the origin of the pests is difficult as the tiny bodies can invade your space without your knowledge.

The presence is visible once vigorous growth occurs, mainly during drought and dry climates, leading to a wilted plant if not controlled on time.

Often the plants affected by pests not only have white specks, but they also dry down and wither up due to excess sap sucking by the sneaky pests.

5. Excess Moisture and High Humidity

Inadequate watering has a less adverse effect on plants than overwatered ones aided by high humidity, as it is home to different fungi and bacteria.

Moisture in the soil and air provides suitable breeding conditions for the mold and spores of powdery mildew.

Also, overwatered plant roots are weaker and prone to be affected by root rot, blocking the passageway for the nutrient transfer to the plant part.

Increased humidity leads to the proliferation of fungi, and if a single plant is affected, none of the others will be spared, which ultimately causes white specks to appear.

The fungi spores can travel even with the air or droplets of water at the time of watering. So keeping the plants together might not be a good idea.

6. Poor Air Circulation

Maintaining space while adding new members is always a priority, but sometimes the topic might slip your head, which might not be a big deal for you, but that’s sure for plants.

The congested area traps the air pockets around the plants, increasing unhealthy fights amongst themselves. Indirectly, the grouping boosts the humidity of the area.

Also, the wrong mix or hard water can lead to compact soil with salt buildups in the air pockets present in the soil, leading to root suffocation and mineral overload.

Thus, turning the leaves brown with pale, creamy white spots.

7. Nutrient Deficiency

One of the most common problems in plants is nutrient deficiency, significantly when a plant cannot absorb the required nutrients from the soil.

Due to the lack of absorption, the nutrient responsible for the green shade of the leaves, mainly iron and nitrogen, gets scant, turning the leaves pale and have white specks.

However, confirm that the white specks are due to nutrients, as the deficiency is first noticed in older leaves.

If the upper new leaves are affected by white spots, the cause may not be due to nutrient deficiency.

How do You Get Rid of White Specks on Plants?

Regardless of the cause behind the white specks on the leaves, gardeners think of the spots as a powder and wipe them off with normal water.

However, the wiping might not work for the fungus, as many reported the spots to appear the next day and with a higher range.

So to get rid of the problem, you need to remove the deep-rooted cause of the white specks. Some of the tips are as follows:

  • Prune off the damaged leaves with sterilized pruners and burn them instead of disposing them in a dustbin.
  • Use pesticides like horticulture oil, neem oil, or jojoba oil to spray over the affected plant.
  • Also, you can prepare a home spray using mouthwash (anti-bacterial) and water in a 1:3 ratio to apply directly to the affected part.
  • Another remedy can be mixing and spraying 1 part of baking soda with 1 quart of water.
  • Install grow light in case of dark rooms.
  • In case of high humidity, place a dehumidifier near the plant.
  • If the condition is severe, go for fungicides like Triadimefon and Bonide.
  • However, it should be done early as the fungicide does not work during the late growing season.

How to Prevent White Specks on Plants?

Applying immediate control measures is effective in a worsened situation, but the white specks can be prevented from the beginning under proper cultural practices.

  • Allow gaps between waterings to let the moisture drain away, and check for drainage holes in the pot.
  • Acclimatize the potted plant before keeping them under harsh growing conditions.
  • Avoid misting the plants regularly, and remember to wipe the plants after each misting.
  • Maintain the optimum space between plants as given in the package, or disperse the plants indoors to minimize crowdedness.
  • Keep the foliage in check by trimming the dense part occasionally.

You can also buy mildew-resistant plants like Lavender, Hydrangea, Melons, Squash, and Cucumber.

From Editorial Team


Early identification and on-time eradication always work to cure the white specks on plants, although it might not completely stop the infestation.

Ensure proper plant growth conditions by keeping moisture, humidity, fertilization, and light in check.

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