Early spring warmth causes some plants to break dormancy too soon with the result that they are damaged if it turns cold again.
Lovely pink or white spikes of bloom and handsome foliage (that is unappetizing to deer) more than compensate for the initial anxiety this plant creates.
All tropical plants must be kept from freezing and stored in a state of dormancy. Lack of warmth inhibits growth, which is why cool temperatures are best.
In the lower mid west, crepe myrtles can be grown as small shrubs.