Viburnum macrocephalum ‘Sterile’ has a rounded habit to 12-20 feet tall and wide. In the Gardens, we keep it pruned back to fit the scale of its surroundings. Also known as “Chinese Snowball’, this Viburnum has spectacular big, rounded 6-8 inch flower clusters in spring. Made up of sterile flowers, this type of flower shape is often called a lacecap.