Diseases for crêpe myrtles

Question

The leafs have fallen and curled on my crepe myrtle. What would cause this.

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Answer 1

Diseases can develop when they are cut back. There is no need to cut contrary to common belief. Leave them alone and hopefully the myrtles can self heal.

Answer 2

This could be due to a drop in temperatures or lack of water. Though they do well in hot southern gardens, they do need regular irrigation.

https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/crepe-myrtle-care.htm