First off make sure the brushtype is Mesh.
On the brush under flowers you can adjust petal curl, bent twist, etc.
These are all keyable attributes. Also if you have 7.0 you could try
creating a pfx modifier, making its widthScale 1.0 and using the force or displacement attributes to shape the petals( like a sculpt deformer ).
The control curves do not affect petals or leaves, just the branches.
As mentioned, you can also simply convert to poly and animate with
traditional methods. I would do this if you have very specific ways the
flower needs to move( for example acting like a character ).
Duncan