The Snowball Tree. Wonderful deciduous form of Viburnum smothered with large, snowball-like clusters of white or green-tinted white flowers - which sometimes age to pink, from May to June. With maple-like, fresh green leaves that become purple-tinted in autumn. Height & Spread 4m. Full sun or partial shade. This is one of our most admired shrubs, when in flower, in our front garden.