Rhododendron Cultivars U

Editorial Note

Entries here are derived, unchanged, from Bean’s articles on Rhododendron hybrids, which, as transcribed into Trees and Shrubs Online format, were unsearchable. These entries, from his sections on “Rhododendron hybrids”, “Deciduous azaleas” and “Evergreen azaleas”, have been extracted and given their own entry under a series of pages Rhododendron Cultivars A, B, etc. Each cultivar’s affiliation to the above categories is noted.

Hybrid rhododendrons follow an unconventional form of nomenclature. All progeny of a stated cross form what was formerly called a grex, now called a Group, and share the same grex/Group name, which is not given inverted commas. For example, all progeny from the cross R. decorum subsp. diaprepes × R. auriculatum are in the Polar Bear Group, and all from any cross between Rhododendron Aurora Group and Rhododendron griffithianum are referred to Yvonne Group, regardless of when or by whom the cross was made. Within the Group individual clones may be recognised as cultivars, being identified by the use of single inverted commas in the usual way: Rhododendron Polar Bear Group ‘Polar Bear’, or Rhododendron Yvonne Group ’ Yvonne Pride’. Reference to the the International Rhododendron Register and Checklist, produced by the Royal Horticultural Society, is advised. A digital version is available through the good offices of the RHS Rhododendron, Camellia and Magnolia Group.

The cultivars presented here represent a fraction of the total diversity of Rhododendron cultivars, comprehensively covered by the Register. The listing on TSO will be developed further when funding permits.