I have never heard of a Japanese Snowball shrub before. This looked like a hydrangea but when I looked it up it proved to be another plant.
"What's the difference between a viburnum and hydrangea" you ask? This is what I found out:
Snowball bushes growing in colder climates are probably hydrangeas. The hydrangeas have a much longer bloom period than the viburnums, with blossoms remaining on the shrub for as long as two months. Hydrangeas bloom in spring and may rebloom in fall, while viburnums bloom in summer.
