K.C.
I live on Cape Cod (Massachusetts) and we have Hydrangeas like crazy. I believe they do like shade and the type of soil (I am sorry - I can't remember if it is acidic or not) is very important. They are not big fans of heat, so I would say (for Kansas) plant them so the cooler part of the day is the time when they get sun.
Best of luck - they are beautiful!