Crepe Myrtle Problems
We planted a crepe myrtle last fall. Bloomed only slightly this summer. Bark is splitting on one trunk and leaves are turning yellow.
Certified GKH Gardening Expert
Did you have a harsh winter? The splitting bark may have been damage from cold or frost.
The yellow leaves can come from a wide variety of things. Most commonly in a young tree, it means that the tree has not established as well as it should. Extra water and some fertilizer may help.
The other common reason is a fungus. Just as a precaution, I would treat the tree with a fungicide. It won't hurt the tree to do so and will take care of any fungus that may be attacking the tree.