Pacific NW gardeners often look to bigleaf hydrangeas when wanting color in shadier garden spots. These deciduous shrubs thrive in morning sun or all-day filtered sun and have a large, pleasing presence when mature. Given free rein, a 'Pure White' hydrangea can reach four to six feet in height and spread almost as wide, making a glorious mound of long-lasting, white mop head flowers. The shrub loses its leaves in the fall, at which point you may prune it back to keep the shrub in check before it leafs out in the spring. While the big leaf hydrangeas can grow in sunnier environments, chances are the leaves and flowers will get burned by the late afternoon sun, regardless of how much they are watered.