To confirm the registration of an Australian native hybrid & view its composition/progeny: (Database as at 1st January 2020 RHS registrations)
For non-Australian Dendrobium hybrids use the Dendrobium Hybrids checklist here
Sarco. Heartlight
= Pinkhart x hartmannii ( has 2 hybrid progeny ) registered: 21/08/1992 by Banks, DavidSpecies composition summary:
hartmannii 87.5% ceciliae 12.5%
Detailed composition:
Sarco. Heartlight = Pinkhart x hartmannii = [Lois x hartmannii] x hartmannii
Lois = ceciliae x hartmannii