Crepe myrtle leaves change color for a few reasons. In autumn it is usually normal fall color. In summer, early yellowing, spotting, and leaf drop often point to cercospora leaf spot, a common fungal disease in the humid South. Drought stress and crepe myrtle bark scale can also cause off-color leaves. The timing and pattern tell you which it is.
- Fall: normal seasonal color change
- Summer yellow or orange spots plus early drop: cercospora leaf spot
- Wilting and browning in heat: drought stress
- Black, sooty coating with white bumps: bark scale
- Pale, off-color leaves overall: nutrient or root stress
Crepe myrtles are everywhere in New Orleans for good reason. They are tough, they bloom for months, and they handle our heat. So when the leaves start changing color at the wrong time, it is worth a closer look. Here are the usual causes and what each one means for your tree.
Normal Fall Color
In autumn, crepe myrtle leaves naturally turn yellow, orange, and red before they drop. This is healthy and expected. If it is fall and the color is even across the tree, there is nothing to fix. Enjoy it.
Cercospora Leaf Spot
If it is summer and you see yellow or brownish spots, leaves turning orange or red early, and the tree dropping foliage from the bottom up, the likely culprit is cercospora leaf spot. This fungal disease thrives in our warm, humid weather and spreads in wet conditions. It rarely kills an established crepe myrtle, but it can strip a lot of leaves. Good air flow, cleaning up fallen leaves, and choosing resistant varieties all help.
Drought and Heat Stress
During a long dry stretch, crepe myrtles may yellow, scorch at the edges, and drop leaves to conserve water. A deep soak during dry spells, rather than frequent light watering, usually helps the tree bounce back.
Crepe Myrtle Bark Scale
If the leaves look dull and you notice a black, sooty coating on the bark along with small white or gray bumps, you may have crepe myrtle bark scale. The insects feed on the tree and leave behind a sticky residue called honeydew, and a black fungus known as sooty mold grows on top of it. The mold does not attack the tree directly, but a heavy layer blocks light from the leaves and makes the whole tree look dirty. Bark scale is treatable, and catching it early makes control much easier before it spreads to the trunk and larger branches.
Powdery Mildew and Aphids
Two other common troublemakers show up on New Orleans crepe myrtles. Powdery mildew looks like a white or gray dusting on new leaves and buds. It shows up most in spring and fall when days are warm and nights are cool and damp, and it can curl and distort young growth. Aphids are tiny soft insects that gather on the undersides of leaves and along tender shoots. Like bark scale, they drip honeydew that feeds sooty mold, so a sticky black film on your leaves usually points back to either aphids or scale. Both problems ease up when the tree has good air flow through the canopy, which is one reason correct tree trimming matters for crepe myrtles.
A Quick Way To Read The Symptoms
The color and pattern of the change usually tell you what you are dealing with. Use this as a starting point before deciding whether it needs treatment.
| What You See | Likely Cause | Season |
|---|---|---|
| Even yellow, orange, and red across the whole tree | Normal fall color | Autumn |
| Spots with early color and leaf drop from the bottom up | Cercospora leaf spot | Warm, wet summer |
| Scorched edges, wilting, and dropping leaves in heat | Drought stress | Dry summer stretches |
| Dull leaves, black film, white bumps on bark | Bark scale with sooty mold | Spring through fall |
| White powdery dusting on new growth | Powdery mildew | Spring and fall |
| Overall pale, thin, off-color leaves | Nutrient or root stress | Any time |
Why New Orleans Weather Makes It Worse
Our climate is close to ideal for the fungi and insects that bother crepe myrtles. Long, hot summers, heavy humidity, and frequent afternoon rain keep leaf surfaces wet, which is exactly what cercospora leaf spot needs to spread. Powdery mildew works a little differently, thriving on the high humidity and heavy dew of warm days and cool nights rather than on soaking rain, and our climate serves up plenty of both. Poorly drained clay soil, common across the metro area, holds water around the roots after big storms and adds stress on top of the disease. Trees that sit in soggy ground or stay crowded against fences and other plants tend to hold moisture in the canopy and see more problems than trees with room to breathe and dry out.
Early Color Can Be A Stress Signal
When a crepe myrtle turns color well before fall, the tree is often telling you something is off at the roots. Drought is the obvious one, but the opposite matters too. Roots that stay waterlogged after heavy rain cannot take up oxygen, and the leaves respond by yellowing and dropping early. Recent digging near the trunk, soil piled over the root zone, or a young tree still settling in after transplant can all bring on off-season color. If the color is patchy or one side of the tree looks worse than the other, look at drainage and root conditions before assuming it is a leaf disease.
Crepe Murder And Why Topping Backfires
Every winter you see crepe myrtles cut back to thick stubs, a practice so common it earned the nickname crepe murder. It feels like a fresh start, but hard topping hurts the tree. The stubs push out clusters of weak, whippy shoots that flop under their own bloom weight, and the large open cuts invite decay and give pests an easy way in. A stressed, over-pruned tree is more likely to show poor leaf color and disease, not less. Crepe myrtles bloom beautifully with only light shaping, so the better move is to remove crossing or dead branches and thin the canopy for air flow. If your tree has already been topped for years, our tree preservation team can help guide it back toward a healthy natural shape over time.
When to Call a Professional
Off-color leaves are often cosmetic, but heavy leaf drop, spreading spots, or a coating on the bark are worth a professional look. Our disease and pest control and fertilization services can get a struggling crepe myrtle back on track.
Get Your Crepe Myrtle Checked
Not sure whether it is a disease or just the season? TurnKey Tree Removal will diagnose it and recommend the right fix. Call (504) 565-2705 or request a free estimate.
Frequently Asked Questions
Why are my crepe myrtle leaves turning yellow in summer?
The most common cause is cercospora leaf spot, a fungal disease that thrives in our humidity. It causes spots, early color change, and leaf drop from the bottom of the tree upward. Drought stress can also yellow the leaves.
What is cercospora leaf spot?
A fungal disease common on crepe myrtles in the humid South. It shows up as dark spots and early yellow, orange, or red leaves that drop in summer. It rarely kills the tree but can strip many leaves.
Will my crepe myrtle recover?
Usually yes. Most leaf color issues are seasonal or treatable. Established crepe myrtles are resilient and typically leaf out fine the next season once the cause is addressed.
Should I remove a diseased crepe myrtle?
Rarely. Most crepe myrtle diseases are managed with treatment and good care, not removal. Removal is only considered if the tree is dead or declining for other reasons.
When do crepe myrtles lose their leaves?
They are deciduous, so they drop their leaves in fall after turning color and stay bare through winter. New growth returns in spring.