Cure Black Leaves on Crepe Myrtle: Easy Solutions

Are your Crepe myrtles leaves turning black and unattractive?

This is a gardener’s nightmare. The crepe myrtles bloom only once in spring so when the leaves start turning black it’s normal to get anxious. But this problem can be prevented and cured if you identify and resolve the underlying issues. 

Sooty black mold, Adverse weather conditions, and Excess fertilization are the main three reasons why your crepe myrtle leaves are turning black.

This article will guide you through the easy solutions and preventative measure to take when treating your crepe myrtles black leaf.

Why Are The Crepe Myrtle Leaves Turning Black?

1. Sooty Mold on Crepe Myrtle Trees

Sooty mold is a fungus that attacks the crepe myrtle trees. It turns the leaves of the crepe myrtles black. This fungus is mainly brought by insects like aphids, bark scales, whiteflies, and mealybugs.

These insects excrete a sticky substance called honeydew. Honeydew is an excellent medium for the growth of sooty mold. Sooty mold coats the whole leaves of the crepe myrtle trees.

As a result, the plant cannot absorb enough sunlight and they cannot photosynthesize very well. The lack of sunlight causes the leaves to turn black.

When the attack of sooty mold is severe the stems, twigs and, even flower buds can turn black with the black mold coating.

But, how do you know if the trees are infested with aphids?

Aphids and whiteflies are very tiny and hard to notice. But the honeydew will make the leaf appear oily and sticky. You may also notice ants trailing over the leaves to get sugar from honeydew.

Control Measures

It’s very important to get rid of the sooty mold fungus before it starts to drop the flower buds. Treat your crepe myrtles with the best and safest fungicide (Our Pick: Bonide Copper Fungicide). Always follow the label directions written on the fungicide.

Make sure your crepe myrtles are in a location with adequate airflow and lots of sun. If the infestation is light, prune off the infested stems. Sterilize the pruning shears before and after working with rubbing alcohol. 

If your keen on making your own remedies for black crepe myrtle leaves, I’ve prepared a few recipes below. These can come in very handy for the natural control of sooty mold.

#Recipe 1:- Baking Soda Spray Recipe


  • 1 tablespoon of baking soda
  • 2 tablespoons of vegetable oil
  • 1 gallon of water
  • 1 teaspoon of liquid dish soap


  • Combine everything and give a good shake
  • Spray on the infected leaves of your crepe myrtle plants.

# Recipe 2:- Epsom Salt Spray Recipe


  • 2 tablespoons of Epsom salt 
  • 1 gallon of water.


  • Mix the salt with the water 
  • Use this as an instant mixture
  • Spray this solution every other week on the leaves as long as the problem continues.

Preventative Measures

The best way to prevent sooty mold is by getting rid of aphids and other insects as soon as possible. When you notice aphids on your crepe myrtles, spray water with a strong jet to wash them off. But this method isn’t always very effective.

Because aphids and whiteflies usually attack in bulk. So, you need to pick the best insecticide for your crepe myrtle that does not harm your beautiful flowers (our pick: Bonide (BND611) – Annual Tree and Shrub Insect Control)

Plant-resistant varieties like Tuscarora,’ ‘Tuskegee,’‘ Wichita.’ ‘Apalachee’ ‘Fantasy’ etc.

Control the insect problems naturally by applying these homemade recipes:

#Recipe:-1 Insecticidal Soap Recipe


  • 500 ml of Alcohol
  • 1 liter of water
  • 1 tablespoon of liquid dish soap


  • Combine everything and put the solution into the sprayer.
  • Spray on both sides of the crepe myrtle leaves.  

#Recipe 2:- Neem Oil Recipe


  • 5 teaspoons of neem oil 
  • 5 liters of water 


  • Mix the ingredients and spray in the crepe myrtle plants every week.
  • You can apply this solution to your plant on a regular basis to prevent these insects.

Tip:  Use a small part of the homemade solution in a small area of your crepe myrtle leaf. If the leaf burns or discolors then dilute the solution with some water. Make it a mild solution and apply it to a small leaf again. If that particular recipe doesn’t your crepe myrtle then skip the recipe and try others

2. Extreme Weather Conditions

Extreme hot weather with the sudden rise of temperature evaporates all moisture from the leaf surface. The leaf of the plant first becomes brown. But as the moisture loss continues the leaves of the crepe myrtle start to become black.

Control Measures

Heatwaves can be harsh on many plants so try giving extra shade to your crepe myrtles. Protect them from continuous harsh sunlight. Provide them with some extra moisture through mulching and extra watering.

3. Excessive Fertilization

Too much fertilizer builds up salts in the soil and causes the leaves to turn black. An excessive amount of any nutrient harms roots and as a result, the roots stop functioning properly. The leaf tips start getting black first, but later whole leaves turn black.

Control Measures

Your crepe myrtles need fertilizer to produce a high-quality bloom. You need to pick a good well balanced blooming fertilizer. It’s best to use a slow-release shrub fertilizer before the blooming period (our pick: Nelson Plant Food Crape Myrtle & All Flowering Trees).

When you suspect an overdose of fertilizer on your crepe myrtle, water them generously to leach out the nutrients. But, make sure the water drains adequately through the soil. When nutrients are balanced the black leaves will soon start to turn green.

Key Takeaways

In this article, we delved into the reasons behind the occurrence of black leaves on your crepe myrtle, and provided detailed information to help you determine whether it’s due to sooty mold bad weather, or fertilizer issues.

Taking care of your crepe myrtle and protecting it from insects is crucial to prevent the recurrence of this problem, but the good news is that it can be easily cured.

Remember to share this article with anyone you know who might be experiencing the same problem with their crepe myrtle.

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