Question
Hello-I live in Tennessee which I believe is zone 7
I transplanted 4 crepe myrtles given to me if I did it now- in the heat of
summer. Of course they are brown even after being planted correctly and
watered well- however in full sun-not shade. I expected them to go into
shock, but I see no sign of new growth and do not know how long that would
take.

How can I tell if the plant is dead or in severe shock?  
Should I continue watering them in hopes of some future new growth?

Answer
MESSENGER, my friend.  Check it out:

http://www.edenbio.com/garden/

Click on 'Find a Retailer' and you'll see a whole list of stores that sell it.  They may not have a clue what you're supposed to do with it.  So let me explain.

Messenger is a Harpin Protein product that accelerates recovery in damaged or weakened plants.  It was discovered by scientists working at Cornell University.  It has 'cured' several of my plants from serious conditions and I can't tell you how impressed I am with it.  It's certainly worth spraying on the victims of your ill-timed transplant.  I can tell you I did the same thing -- this year! -- on a few spring blooming perennials.  What was I thinking? I don't know.  Just like you, the soil was carefully prepared and amended, and I just scheduled it at the wrong time of year.

About.com writer Marie Ianotti writes all about Messenger:

http://gardening.about.com/od/gardenproblems/gr/Messenger.htm

Thanks for writing.  Good luck with this stuff -- spray it on, it's fantastic.