Below is a list of species. The * denotes the species and hybrids that we have in our nursery:

As you can see, H x orientalis is a very diverse hybrid and there is a school of thought that suggests that the species H.orientalis is almost extinct due to the hybridisation that has occurred in the wild. In fact it is know very difficult to say with certainty that you have a true species rather than a hybrid as most of the plants in cultivation may have hybridised without our knowledge.

Some of the hybrids have given rise to the colours we see today, for example crosses with H.odorus tend to give yellow hybrids, H.torquatus gives darker colours and H.cyclophyllus gives green coloured flowers.