Spiraea cantoniensis, or Bridal-wreath Spiraea, is a deciduous perennial shrub typically grown as an ornamental feature in gardens. The plant can reach a height of 6 feet, tends to be twiggy and spreading into a fountain-like form, and displays frothy, pompom-like clusters of snow-white flowers along the terminal of arching branches. The bush blooms in May in its native China; hence the common name, May Bush.