Taxonomy

• The snowball bush (Viburnum opulus 'Roseum') belongs to the Caprifoliaceae family. The snowball bush denotes the sterile specimen of Viburnum opulus, as it produces no berries. The fertile cultivar of Viburnum opulus goes by the common name of the European cranberry bush and produces red berries. In contrast, the hydrangea (Hydrangea paniculata) belongs to a completely different family, the Hydrangeaceae family.
  
  

Form

• The snowball bush takes the form of a rounded, dense shrub that sends out branches from the base of the shrub and reaches up to 8 to 10 feet high at maturity.
  
  The hydrangea, on the other hand, produces heavy branches from a central point, which then arch over and cascade like a fountain, according to the University of Connecticut. In addition, the hydrangea grows 10 to 20 feet tall and wide. The branches have a gray cast to them and the stout stems grow reddish-brown in color.
  
  

Foliage

• Noticeable differences between a snowball bush and hydrangea lie in their foliage. The rough textured leaves on a snowball bush have three lobes that resemble a maple tree leaf, according to the University of Arkansas.
  
  The dark green leaves on a hydrangea, though, have no lobes, instead forming one long elliptical shape with serrated edges. These leaves grow opposite one another and do not turn colors in the fall.
  
  

Flowers

• The flowers of the snowball bush give it its name, with round clusters of white flowers bursting forth during mid to late spring. These clusters measure around 3 inches in diameter.
  
  The very fragrant flowers on a hydrangea bloom between mid July and September. The white flowers mature to a light pink and form a cone-shaped cluster of flowers called a panicle that stretches 8 inches long and 6 inches wide.
  
  

Growing Culture

• A very hardy shrub, the snowball bush thrives in full sun to partial shade and adapts to varying soil types. In addition, this winter hardy plant proves easy to grow.
  
  In contrast, hydrangeas prefer full to partial shade and need moist, fertile soil for best growth. The hydrangea does not grow well in hot, dry conditions and lacks hardiness.