I am not a native and only have 9 years experience with them, but they do seem to leaf out slower than other trees. I don't think I would worry, especially since we have had two unusually cold years. I was warned that the colored flower types are more susceptable to damage than the white type and that appeared to be true. Two of my initial planted trees were severely damaged in their second year and lost all or most of their initial shape. I had to rely on the new growth. It has not been as straight as the initial plant, but they are coming around and the more crooked shapes may turn out to be attractive; it is still too soon to be sure. In any case, I think you may as well wait and see what happens. You can always cut later or next year.

Chas045 is right. Some colors spring forward better than others so it is a bit early to tell. I would wait another month and then trim away any dead branches. You will need to prune them into a tree shape if that is what you want. They tend to want to be large bushes otherwise.

Gee,

Contrary to popular belief, there is such as a crape myrtle tree.

There are trees, (depends on variety), then the shrub kind, then the miniature kind.

If you bought the shrub kind, it will never look like a tree. It will look like a big shrub.

It won't get the kind of strong tree barks, I can't explain it. I bought a tree 6 years ago,

It was 4 ft tall. I paid 15.00 for it, because I bought it in the fall and they were trying to get rid of them. It is 30 feet tall now. Seriously. I also bought other shrubs, which look exactly like shrubs, not trees.

If you want a big, fast growing tree, look for the tree. Google online Crape myrtle trees, and see what I am talking about.

Crape myrtles don't die in the Carolinas. They are hardy things.