Answer: First off I apologize for the delay in answering your question. Crape myrtles grown as container plants can be planted any time but midsummer is to be avoided because it is so hot and therefore stressful on the plants, and they are very slow to establish if planted in midwinter. So, ideally plant in spring or early fall.
Seedlings generally will not come true if taken from a hybrid cultivar so these shrubs/trees are usually propagated by tip cuttings. Here are instructions for how to do that. You may need to cut and paste the complete url into your browser to make it work correctly.
I hope this answers your question.
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