Unfortunately, just like most if not all plants can turn white from time to time, rhododendrons are no exception.
Fortunately, the causes of leaf bleaching in rhododendrons are fairly easy to identify and treat once you know what to look for.
So here are those causes, what to look for, and how to treat your plant today.
powdery mildew
The most easily identifiable cause of white leaves on a rhododendron is attributed to powdery mildew.
If you notice a white, powdery substance covering parts of the plant or the entire plant, you have a powdery mildew problem.
Powdery mildew is a fungal problem that can spread in high humidity, or just be caused by luck, as this material can travel for miles through the air.
Unfortunately, it can spread very easily, so it’s best to get it treated as soon as it’s noticed.
Solution
One way to treat powdery mildew on a rhododendron is to mix a tablespoon of baking soda to a gallon of water, then spray the affected parts of the plant.
Another way to deal with this is to use effective fungicides like neem oil to spray the plant as well.
Both are great options and will get the job done, so you no longer have to worry about white dust on your Rhododendron.
harmful
Sometimes rhododendrons can be overrun by a variety of pests including rhododendron borers, lace bugs, spider mites and aphids, to name a few.
Many pests feed on the leaves, losing nutrients and in turn causing white or pale leaves.
The mites leave behind a fabric-like material, so this would be an instant treat for these particular pests.
Other signs that you have a pest problem include curled leaves, drooping leaves, yellowing leaves, holes, white or black spots, and bumps in the foliage.
You may even be able to spot the parasites yourself, but it depends on the type you’re dealing with, as some are so small you can’t even see them, just the symptoms that follow.
Solution
The first thing to do when dealing with a pest problem is to isolate your rhododendron from other plants to prevent it from spreading.
Now that you have done that, there are mainly 3 different ways to get rid of the errors.
One way is to use only water to spray them on the plant.
Another way is to use a cotton swab soaked in alcohol to remove them one by one by hand.
Finally, you can use some type of pesticide or insecticide to get rid of it.
Personally, I always seem to use neem oil as it’s great to have on hand as it’s also an effective pesticide and fungicide.
I recommend this neem oil if you need these things.
little light
Another common cause of rhododendron leaf whitening can be low light or lack of light in general.
While rhododendrons can grow quite well in shade and generally prefer full sun, they still need plenty of indirect light to grow and look their best.
Lack of light can cause chlorosis, which is a loss of chlorophyll needed to complete photosynthesis and get those completely green leaves.
When a rhododendron has chlorosis, the leaves may turn white, pale, or yellow.
Other signs of too little light are curled leaves or stretched leaves known as etiolation.
Solution
If you notice any of the above symptoms, it’s time to find a new location for the plant where it can get plenty of light each day.
That said, you don’t want to put your Rhododendron in full sun all day, just a few hours a day is ideal.
You want a location that gets lots of bright, indirect light, such as under balconies or trees.
When grown indoors, most windows will work just fine.
Just be sure to keep the plant a bit away from the window to prevent the sun’s rays from scorching the leaves.
Once the light issue has been resolved, your Rhododendron should return to its normal color.
conclusion
So there you have it, the main reasons why you have white leaves on your rhododendron and the steps needed to fix them and get them back to normal.
As always, I hope you find this useful so you don’t have to worry when issues like this arise.