6 Causes of Bougainvillea Leaves Turning White [Solutions]

Are the leaves or flowers of your bougainvillea turning white?

Various ornamental plants combine colors with our surroundings. Bougainvilleas are the best of that kind.

Therefore a shabby look with white leaves, white flowers isn’t much expected, right?

Multiple reasons are responsible for the whitening of leaves or flowers of bougainvillea. For instance, sunburn, too cold temperature, chlorosis, genetic mutation, powdery mildew, leaf miner attack, etc.

In this article, I have discussed these reasons in detail & provided both control & preventive measures.

So, If you want to know the reasons why the leaves or flowers of your bougainvillea are turning white & also the solutions, then walk with me!!

Let’s begin-

Reasons of Bougainvillea Leaves & Flowers Turning White

Purple heatlhy bougainvillea

In this article, I have discussed the 6 most important reasons. Some of them are equally responsible for the whitening of both leaves & flowers. And some of them are responsible for particular ones.

1. Sunburn

Have you ever wondered how much heat is too much for tropical plants like bougainvillea?

Well, Bougainvillea is a sun lover, no argument upon this! But everything has its limits, right?

Over 38-degree Celcius is considered to be too much heat for bougainvillea.

In such temperatures, directly exposed bougainvilleas face sunburn.

Causes & Symptoms

Sunburn occurs to bougainvillea when three agents are available-

  1. Direct exposure to the sun
  2. Exposed for a longer period
  3. Temperature is above 38-degree celsius

If all three are confirmed, then extreme heat burns up the exposed layer of the leaf or bract tissues.

Due to the burning, Leaves & flowers of bougainvillea begin to turn white.

Control Measures

  1. Probably you know what is the first thing to do! Yes, you are right. Arrange shades for your bougainvillea
  2. If you are thinking of clearing out the burned leaves & flowers, let’s not do it. Let them stay. They will provide shades to the other leaves & flowers.
  3. It would be helpful if you could increase the humidity. Manually, spraying cool water mists over the foliage is quite okay. But a humidifier would do just fine. (our pick: TaoTronics Humidifiers)

Preventive Measures

  1. Try to grow a native cultivar. That will resolve many issues.
  2. If you have just brought the plant, you might want to pay some attention to “Hardening”. Before leaving it to the direct sun for 6-8 hours, try to adjust your bougainvillea with your garden environment.

So, how would you do it?

Initially keep the plant to direct sun for 2 or 3 hours, and then in shades for 1 hour. Repeat this for one week or less. Well, congrats! You have hardened your bougainvillea!!

2. Very Low Temperature

Bougainvilleas are the Aphrodite of tropics. They are native to that region. This means bougainvillea requires a 21-30 degree Celcius temperature on average.

Bougainvillea can tolerate a temporary cold temperature-may be for 1 or 2 days, but, 4 degrees celsius is the limit.

Causes & Symptoms

Temperature below 0 degrees Celsius can induce critical damage to both flower & leaves of your bougainvillea.

Low temperature affects nutrient uptake & creates freezing conditions. And the result? The leaves & flowers of your bougainvillea start wilting & turning white.

Control Measures

Sorry to say, but, once your bougainvillea starts wilting & turning white because of too cold temperature, you don’t have much to do.

If the freezing weather is still on, you can cover your bougainvillea with polythene & remove it as soon as possible.

One thing to mention, while covering, try to avoid touches between foliage & polythene. Because polythene can retain moisture against the leaves & flowers & cause more freeze injuries.

Preventive Measures

  1. Keep weather records beforehand to get prepared.
  2. Bring your bougainvillea inside if there is below 4-degree Celsius going on.
  3. Cover your bougainvillea with plastic before cold weather hits. & remove as early as possible. It is a temporary measure and only for bougainvilleas which can’t be moved inside.

I4. Interested in an artificial lighting system? Give it a thought. (our pick: GE BR30 LED Grow Lights for Indoor Plants)

3. Powdery Mildew

“I wish I didn’t meet with this guy”- have you ever thought of something like that?

If so, then you might want to protect your bougainvillea from powdery mildew. Yes, you heard me!! It is a fungus, a potential destructionist for your bougainvillea.

Both leaves & flowers of Bougainvillea can be affected by powdery mildew but leaves are more prone to it.

Cause and Symptoms

Warm & humid weather is what powdery mildew needs. Densely arranged plants with minimum airflow create the exact environment.

After infestation, initially, you will see white spots at the end of the leaves or flower petals. Trust me! they won’t take much to spread all over it. White powder-like structures will cover the surface entirely.

And you will discover that, in a very short time, the leaves or flowers of your bougainvillea have turned white!

Control Measures

The first step is cutting off infected parts and destroying them.

Secondly, I am suggesting some very effective home remedies-

Neem oil

Try neem oil (Our pick: Organic Neem Bliss 100% Pure Cold Pressed Neem Seed Oil) & you will see the effect within 24 hours.

Milk

Milk creates radicals while contact with the sun causes hostile conditions for powdery mildew.

Mixture: 4 parts of milk in 6 parts of water

Mouthwash

Sounds funny? Try it. Thank me later.

Mixture: 1 part of mouthwash in 3 parts of water

Vinegar

Mixture: little less than 1 tablespoon vinegar in 1-liter water.

Both surfaces of leaves or flowers of your bougainvillea should be thoroughly sprayed.

Preventive Measures

  1. Make some space for your bougainvillea. Maintain some distance with other plants. It will increase airflow.
  2. Prune your bougainvillea accurately for the same purpose
  3. Bougainvillea is a sun-loving plant. Ensure proper sunlight.

4. Genetic Mutation

Causes & Symptoms

Do you know those bright flowers of bougainvillea are not actual flowers?? Yes, you heard me!

Those are modified leaves called bracts. The actual flower is a bit tiny & usually found inside the bracts!!

You know, Bougainvillea displays different colors, for example – pink, red, white, yellow, etc. Sometimes because of genetic mutation, flowers change their colors.

So, suppose you bought a pink bougainvillea & now the flowers of your bougainvillea are turning white, then there is a teeny tiny possibility of complex genetic mutations.

Solutions

Okay!! This can be a pretty rare solution!! I’d rather enjoy the new color!!

5. Chlorosis

Chlorosis is so common in plants that most gardeners don’t even bother initially. But severe chlorosis will force you to regret it.

Causes & Symptoms

The green coloration of leaves is due to the presence of a green pigment called chlorophyll. Lack of chlorophyll causes the leaves to turn yellow, pale green, or white.

Chlorosis exhibits a unique pattern of symptoms. Leaves turn yellow, pale green, or white whilst the veins remain dark.

Your bougainvillea needs Iron to form chlorophyll. That’s why the deficiency of iron is one of the main reasons for chlorosis.

Control & Preventive Measures

  1. Soil pH controls the availability of iron in the soil. Bougainvillea can uptake iron from the soil if the pH is between 5.5 – 7. To maintain this pH, add organic fertilizers like vermicompost. It will enhance the acidity of the soil.
  2. Use chelated iron fertilizers.

But remember, after providing the fertilizers to Bougainvillea, don’t forget to water them well.

6. Leaf Miner Attack

I might say that Leaf miners are the artists of the entire pest world. Sounds stupid, right?

Trust me! Once you see the symptoms, you won’t disagree.

Cause & Symptoms

Leaf miner attack is a serious Leaf problem of Bougainvillea.

Leaf miners are specifically larvae that cause outrage on your bougainvillea leaves.

These larvae dwell inside the leaves. They create tunnels by absorbing cells like a miner.

These tunnel-like structures inside the leaf express themselves as whitish channels over the surface of the leaves.

A substantial amount of infestation will turn your bougainvillea leaf completely white and the leaves start falling off.

Control Measures

  1. First & Foremost, cut off the infected leaves & crush them. Pay attention- Do not mix the infected leaves with the compost pile.
  2. Let me recommend to you a home remedy. Prepare a pesticide by stirring 4 tablespoons of vegetable oil & 2 tablespoons of liquid soap into 1 liter of water. Spray it all over your bougainvillea leaves thoroughly.
  1. Clear out the leaf miners using Commercial pesticides. My recommendation for you (our pick: Monterey LG6150 Garden Insect Spray, Insecticide & Pesticide)
  2. Most gardeners rely on Neem oil as a natural pesticide. Numerous brands are available in the market. I am suggesting you (our pick: Organic Neem Bliss 100% Pure Cold Pressed Neem Seed Oil)
  3. Have you ever thought about biological control? If you are interested, Leaf miner predators can be your concern. They are beneficial insects that swallow leaf miners.

And one more thing, during biological control, be cautious about your pesticide spraying. You may kill your warriors.

Preventive Measures

  1. Ensure fulfilling your bougainvilleas’ necessities precisely. This will keep your bougainvillea healthy.
  2. Use a leafminer trap to avoid this trouble in the first place. But remember to set the trap some feet away from your bougainvillea.

Conclusion

I think if plants could talk & walk, we could’ve helped them earlier, more effectively. As it is not possible in reality, we have to understand their language, right?

However, now you know the reasons why the leaves or flowers of your bougainvillea are turning white.

It’s your turn now! Watch closely. Take good care of them & Thanks for coming so far. I hope you have found it helpful.

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