Invincibelle Spirit hydrangea, new in 2010,  is pink, no matter the soil type.  Invincibelle comes from the smooth leaf hydrangea, or Hydrangea arborescens ‘Annabelle’  which is native to Eastern side of North America.  One of my favorite things about these is that they bloom on new wood, so prune away!  No worries about cutting off next year’s flowers.  The flowers appear early summer until frost and are a welcome contrast to the blues and whites of other hydrangeas.  For every Invincibelle sold, $1 is donated to the Breast Cancer Research Foundation (plants helping people, again).   Growing 3-4 feet tall, this hydrangea prefers part sun to sun.  Go Pink!