Hydrangeas are a spectacular addition to summer shade gardens, thriving in all-day filtered sun, or morning sun and afternoon shade. 'Hortmablo' (aka Cape Lookout) is part of the Seaside Serenade series of hydrangeas, boasting of thick green foliage and a stronger resistance to scorching on hot summer days. This variety produces large flower heads that emerge a pale green, then turn pure white, with hints of pink as they age.  'Hortmablo' forms a rounded mound about three feet tall and wide, with the large leaves taking on bronze hues before dropping. Prune it back in the fall to late winter to keep the shrub in check when it leafs out in the spring.