Summer Joy
H. 'Summer Joy'
Leaves have white centres with margins of blue-green.
Photo credit: Dave Harrison

Alternative: H. 'Great Expectations'
Plant Size
  Large: 21 " x 48"  
Leaf
  12" x 10"; white, blue-green margins  
Flower
  Near white  
Parentage
  Sport of H. 'Blue Moon'  
Summer JoySummer Joy