Last Updated: September 15, 2020
Many years ago coerulea hybridizing was considered to be a dead end. There were not many options to start with, hybridizers were limited to Phal. violacea var coerulea and Phal. pulcherrima var coerulea as a source for the "blue" color. They quickly found that breeding almost anything outside of these two specific forms resulted in 100% magenta flowers. There were a few happy accidents where successful pairings happened outside of these two species, but even then subsequent crosses would result in more magenta flowers. This lead to the perception that coerulea hybridizing was a dead end that could not progress. The big mistake at the time was trying to apply standard Mendelian inheritance to these lines of breeding.
We now understand more about the genetics and inheritance and it is not as simple as just dealing with dominate and recessive traits. The coerulea form is created by mutations in the Anthocyanin pigment pathways and those mutations are effectively errors that are easily fixed when a parent with a complete Anthocyanin pigment pathway is introduced and/or a coerulea with a different mutation.
What we have found is different coerulea mutations are generally not compatible with each other unless other genetics are introduced that stabilize the mutation. That is easier said that done, so it's generally important to understand the different groups of coerulea mutations and the related compatibility in order to successfully plan out coerulea crosses.
For a very long period of time we only had two primary groups of coeruleas to work with. Type 1 and Type 2 as it turns out are completely incompatible. So breeding between Type 1 and Type 2 coeruleas will about 95% of the time produce 100% magentas, subsequent attempts to produce coeruleas from that progeny will also produce 100% magenta flowers.
Type 1 Coeruleas:
- Phalaenopsis violacea var coerulea
- Phalaenopsis pulcherrima var coerulea
- Phalaenopsis equestris var alba (only some specific cultivars)
- Phalaenopsis Siam Treasure var coerulea (NOTE: we do not know if P. lowii is inherently compatible with all Type 1 or just the resulting coerulea form of Siam Treasure.)
Type 2 Coeruleas:
- Phalaenopsis violacea var indigo
- Phalaenopsis bellina var coerulea
- Phalaenopsis equestris var coerulea
- Phalaenopsis equestris var cyanochilus
This means that breeding pulcherrima and standard coerulea violacea hybrids with indigo violacea lines is mostly impossible without some extra help.
In recent years additional coerulea species and even new coerulea mutations in existing hybrids have emerged, so the number of different coerulea mutations has increased greatly complicating keeping up with compatibility within different combinations of coeruleas. Right now we have incomplete data for all of the different possible combinations, so this information is going to be updated on periodic basis as new data fills in the gaps. As such, the classification of different coerulea types will likely change as better data is available. But the following information represents the current understanding of the additional coerulea mutation types.
Type 2B Coeruleas: - new indigo compatible species, these do not appear to always be compatible with each other suggesting there are different mutations for each of these but they are compatible with the indigo lines. They are also at times compatible with Type 3 hybrids.
- Phalaenopsis tetraspis var livida
- Phalaenopsis tetrapsis var bruneola
- Phalaenopsis lueddemanniana var coerulea
Type 3 Coeruleas: - new Dragon Tree Eagle coerulea mutation
- Phalaenopsis Mituo Prince
- Phalaenopsis Mituo Princess
- all related coerulea with coerulea mutation going back to DTE
Type 3B Coeruleas: - new Taiwan violacea var coerulea lines
- Phalaenopsis violacea var coerulea (Taiwan strain)
Type 3C Coeruleas: - Type 3 lines combined with Type 2B
- Phalaenopsis parishii
- Phalaenopsis modesta var coerulea
- Phalaenopsis javanica var coerulea (early data suggests this falls under Type 2B)