Question
I live in S.C. and have full sun in my yard.  Is there any hydrangia that will grow in full sun?

Answer
Margaret,
The hydrangea that does best in full sun is the Pee Gee Hydrangea, Hydrangea paniculata grandiflora.  This is the one that you sometimes see trained as a small tree, with white flowers that age pink in the fall.  This is an easy, hardy shrub to grow.  There are several new varieties you might want to check out including LimeLight and Pinky WInky.

If you want to grow the blue or pink mop-head hydrangeas (Hydrangea macrophylla) in full sun you have to be able to keep it moist - you need to take that "hydra" part of it's name seriously!.  This may mean watering every day if it gets in the 90's where you live, but at the same time it's best if your soil is well drained so that the roots don't rot.

That said, the blue and pink hydrangeas really do better, and the flowers last longer, in part shade. Early morning sun and afternoon shade is best.  Where I live I see that those hydrangeas that are planted in full sun get dried, brown flowers very quickly where as the ones planted in part shade stay blue all summer and into the fall.

all the best,
C.L.