06/11/2026
Ants in Crepe Myrtles: The Hidden Cause of Progressive Dieback
If your beautiful crepe myrtle is looking thin, showing branch dieback, or has sticky black leaves, ants could be the real culprit behind the scenes.
What’s happening?
Ants don’t usually eat the tree directly, but they “farm” aphids and other sap-sucking insects. They protect these pests from natural predators, allowing huge populations to explode. The aphids suck sap from the tree, secrete sticky honeydew, and cause sooty mold — all of which stresses the tree and leads to progressive dieback over time.
This is very common in Texas crepe myrtles during warmer months.
How to Protect Your Trees:
Early monitoring — Catch aphid activity before ants take over
Promote beneficial insects (ladybugs, lacewings) that naturally control aphids
Proper watering and mulching to keep the tree healthy and resilient
Avoid over-fertilizing, which can attract more sap-sucking pests
What to Do Once You Have an Infestation:
Targeted treatments to break the ant-aphid cycle
Horticultural oils or soaps for softer, tree-safe control
Systemic treatments when needed for heavier infestations
Pruning out heavily affected branches to improve airflow and reduce stress
We always start with a proper consultation and assessment. Not every ant sighting means you need heavy treatment — sometimes simple cultural changes make a big difference.
If your crepe myrtles (or other trees) are showing sticky leaves, black soot, or thinning canopy, don’t wait for more dieback.
📸 Drop a photo in the comments or message us — we’re happy to give general advice.
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📍 Serving San Antonio, La vernia, New Braunfels and surrounding areas
Let’s keep your landscape healthy and beautiful all season long!