There are many reasons behind a begonia with white spots, like disease damage, insect infestation, sun scorching, water spots, and over-adding fertilizers. The good thing is that these causes are fixable.

Begonia With White Spots

Please continue reading to find out what to do to treat them.

What Causes Begonia With White Spots?

White spots on Begonia are usually caused by disease attacks. Moreover, if you add more fertilizers, the plant can also have white scars or marks. Furthermore, environmental stresses like high humidity and chemical exposure can also cause white to gray spots.

– Disease Attack

The begonia plant, commonly called polka dot begonia, is prone to both fungal and bacterial diseases. The common one that causes whitening of leaves and stems is powdery mildew. It is a fungal disease that first impacts the older and weaker leaves. You will see white blotches or spores on the whole plant. If you don’t do anything, powdery mildew can cause plant death.

Stem rot is another undesirable condition in which a white powdery substance or spores emerge on the stem of the begonia maculata plant. The white spores can grow more if the environment is humid or wet.

Pythium root rot is another disease impacting begonia maculata leaves, stems, and roots. First, the fungus attacks the roots, adversely affecting their ability to uptake moisture and nutrients. This makes plants weak. With time, the impact of this disease gets visible on the stem and leaves as it causes discoloration.

In addition, leaf spot is a harmful bacterial disease affecting many plants, including angel wing begonia. In this, small circular spots first emerge on the leaves. After some time, you will see them turning brown and eventually whitish gray.

– Insect Infestation

Insect attacks can also cause white marks on polka dot begonia. The ones you will commonly find around your begonia plants are mealybugs and whiteflies. Mealybugs are white and are usually found on the stem and underside of the leaves. So, looking at plants infested by this insect from a distance, they will appear white.

Furthermore, these insects suck the cell sap, reducing the leaves’ chlorophyll-containing cells. When this happens, small white blotches will emerge. In addition, tiny white-winged insects also leave a dusty white powder on the leaves. So, plants infested with insects also cause polka dot begonia to appear white.

– Sunburn

Begonia leaves can become white when you grow plants in an area where excessive light with high-intensity falls. The reason is that plant cells can tolerate light for a specific time and intensity. If both are in extremes, then cells will start to die.

Causes of Begonia With White Spots

First, you will notice the upper leaves turning yellow. The sunburn causes a brittle yellow appearance. With time, the yellow leaves will start discoloring to whitish gray and eventually fall off.

– High Humidity Levels

High humidity can also be the reason behind white-spotted Begonia. Polka dot begonia loves humidity levels up to 50 percent. If they are more, then evaporation will not occur smoothly. The reason is that when the humidity levels are high, there is already a lot of moisture in the air. So, leaves will find it hard to evaporate.

When the excessive moisture doesn’t leave the leaves of the polka dot plant, they will start to turn white. Moreover, the chances of fungal diseases and plant rotting are higher when the humidity is high. Both of these problems can also lead to plants becoming white.

– Water Spots

Overwatering begonias is never a good thing. It is even worse when the water you apply is hard. This water is high in minerals, including calcium, magnesium, and manganese.

Some sprinkles can fall on lower leaves when you give hard water to polka dot begonias. When these sprinkles evaporate, they will leave minerals that appear as white marks. Generally, water spots occur when you add tap water. So, test the water quality immediately if you see these spots on your plants.

– Overadding Fertilizers

When you notice white dropping leaves after applying fertilizers, you have added them too  generously – adding more nutrients than required is never a smart move. It is because excessive nutrients change the pH of the soil and cause fertilizer burn on the roots.

Roots will not perform their role when these conditions impact the plant’s health. First, the leaf tips will start to curl. The yellowing will also occur with time. These yellow spots will then turn white because of the death of tissues. After some time, the white leaves will fall off.

– Chemical Damage

Begonia maculata toxic resistance is not good. So, the cells will die when the plant is exposed to any chemical. This will also reduce the chlorophyll in the leaves, which will impact photosynthesis. As a result, Begonia will become white and can even die if you don’t protect it from the chemicals.

How Do You Fix White Spots on Begonia?

To fix white spots on Begonia, you should first cut off any diseased part and apply fungicides or bactericides to control the fungal and bacterial attack. You should also eliminate insects and add organic fertilizers to keep the plants healthy and spotless.

– Protect Plants From Diseases

When Begonia gets infected by diseases, you must start the treatments as soon as possible. First, cut off any diseased part you see. Then, make sure to remove all the excess moisture in the soil. It is super important to dry the soil if you want any treatments to work and to avoid further polka dot begonia problems.

It is also recommended to change the top layer of the soil and replace it with a new well-drained one. This will make the soil dry and also take away most of the harmful fungi and bacteria. Next, uproot all the weeds in your garden, as they can also spread diseases.

If the white patches spread to all parts, apply appropriate fungicides and bactericides. After this, you should water Begonia with care and follow plant care measures, or the diseases might attack again.

– Get Rid of Insects

One of the biggest begonia maculata problems is insects. That is why one of the most asked questions is how to control their infestation. If you see more of them, use organic repellents like Neem oil, Wood ash, baking soda, etc.

Remedies for Begonia With White Spots

In case of severe infestation, use chemical insecticides as they are more effective and can control their population in just a few hours. Make sure to follow precautions like wearing a mask and gloves.

– Grow Plants in Appropriate Locations

You should take care of the light requirements of begonia if you want to avoid seeing leaf discoloration. Plants should get bright indirect light for at least six hours. So, choose a spot where they will receive this much light.

It is easier to do polka dot begonia care indoors. It is best to use Grow lights for indoor plants to provide optimal lighting conditions. If you don’t have these lights, put these plants near a window or opening. Make sure to follow our detailed guide on how to repot a Begonia safely.

– Smart Pruning and Propagation

You can also propagate begonia maculata to protect the whole garden. When you prune offshoots, the air passage will improve, lowering the impact of humidity and environmental stresses.

So, make stem cuttings with a sharp knife or scissors. The begonia maculata cutting should be around one inch long. It would be best to plant the cutting into well-drained and nutrient-rich soil to avoid complications.

You will see new begonia maculata grow faster than expected when you provide all the optimal conditions. Generally, the cutting will take around one week to grow. You should also follow begonia maculata care practices if you want your plants to avoid any problems.

– Add Organic Fertilizers

It’s always wise to choose organic fertilizers over chemical fertilizers. It is because they don’t cause pH change and do not lead to toxicity. The best one is compost, but you can also add bone meal, blood meal, or any other organic fertilizer you have. This will keep the plants healthy and green.

Conclusion of Begonia With White Spots


Whitish spots appear on begonia when it faces different problems. In this article, every cause was discussed, along with easy solutions. To revise everything, here are the main points:

  • When plants get damaged by diseases, follow proper preventive measures and apply fungicides and bactericides.
  • Use organic repellents like neem oil to shoo away the pests. When you see more insects, apply chemical insecticides.
  • Plants should enjoy sufficient light to stay in their colors.

Follow these points, and your Begonia will never have any white marks or spots!

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