about the botany and the name change from Eucalyptus ficifolia to Corymbia ficifolia. The reason why the group of gums that include the red flowering gum were separated from Eucalyptus were that there are considerable differences. Corymbia are generally known as the bloodwoods and they have a special characteristic of being terminal flowering, with all those big sprays of flowers held on the end of the branches, which can be seen from a very long distance away. Many of what have remained as Eucalyptus flower way back inside the canopy on the axillary buds, unlike the terminal buds of Corymbia. Indeed, many people are surprised to hear that all gums are ‘flowering gums’; the red flowering gum just holds its flowers where they can be easily seen. Corymbia shares this terminal flowering with Angophora, sometimes known as the apple gums, of which the Sydney red gum, Angophora costata is probably the best known in cultivation. The botanists faced the dilemma that Corymbia gums were more closely related to Angophora, both being terminal flowering and sharing some other characteristics. Being closer to Angophora, it was either include everything within the one genus of Eucalyptus, or split off the bloodwoods and create a separate group for them sitting in between Angophora and Eucalyptus.
Which brings me to the genetic improvement of the red flowering gum, a brilliant but unreliable species, in the genetic sense that you don’t know what you’re getting! One of the more amazing projects that I’ve seen in my career as a plant breeder happened up in Queensland. A fellow by the name of Stan Henry, a retired horticulturist, wanted to grow a red flowering gum in his home garden but he was in the humid climate of coastal central Queensland. He watched a number of his Corymbia ficifolia die from the heat and humidity, and from the leaf spot that they tend to get when they’re grown in Sydney and further north (you can grow them but they look very ratty and not a good garden specimen).
The strategy that he then chose was to hybrid