Rhododendron 'Heureuse Surprise', which is a 1855 Sunningdale Nursery Ghent hybrid, has been determined to be a tetraploid using flow cytometry by
Dr. João Loureiro, Dr. Silvia Castro, José Cerca, and Mariana Castro
Plant Ecology and Evolution Group,
Centre for Functional Ecology,
Department of Life Sciences,
Faculty of Science and Technology,
University of Coimbra, Portugal.
To date, all Ghent deciduous azaleas have tested as triploid or tetraploid.
Summary of Ploidy Levels
Triploid 'Bronze Unique',
Triploid 'Daviesii',
Triploid 'Deep Rose',
Triploid 'Gloria Mundi',
Triploid 'Josephine Klinger',
Tetraploid 'Bijou des Amateurs',
Tetraploid 'Comte de Flandre',
Tetraploid 'Heureuse Surprise',
Tetraploid 'Ignacea',
Tetraploid 'Julius Caesar',
Tetraploid 'Lelia',
Tetraploid 'Madame Gustave Guillemot',
Tetraploid 'Nancy Waterer',
Tetraploid 'Oscar I',
Tetraploid 'Raphael de Smet'
Source: Arnold Arboretum Accession Number: 7105
John and Sally Perkins
