Question
what could be wrong with my 2 year old giant butterfly bush it has lost all of its green and flowers and looks like it is drying completely out and is going to die help me ?  stan

Answer
Probably too much water which will cause a root rot causing the leaves to turn brown and fall off.  I would cut the plant back some and wait for the new growth and see how it looks.  The plants are very shallow rooted and the top growth may be more than the root system can handle.  It is easier to replace the shrub than it is trying to treat with a fungicide.  Good Luck.