Cattleya mossiae var. alba

[Rosim_in_BR]

One of the nicest things of raising orchids since they are small seedlings is the surprise of the first flowers. This is a cross beetween an alba and a suave that bloomed pure alba! It is not first class, but I don't mind. The important is the joy you take from getting a small seedling and grow it up until an adult, flowering plant!

[stefpix]

why "not first class"? looks good to me. what does it need to be first class?

[RosieC]

Wonderful, looks just brilliant to me. I love that yellow on the lip.

Something I don't quite understand about Alba forms accross all orchids. Sometimes they have to be completely white, sometimes like this they have some colour. How is it decided what makes it 'Alba'.

[trdyl]

I love the amount of yellow in this one's lip.

[Bruno De Toni]

It looks pretty good Mauro.

[pheli]

What a beauty! I especially like the yellow on the lip.

[Rosim_in_BR]

Originally Posted by RosieC

Wonderful, looks just brilliant to me. I love that yellow on the lip.

Something I don't quite understand about Alba forms accross all orchids. Sometimes they have to be completely white, sometimes like this they have some colour. How is it decided what makes it 'Alba'.

Rosie, your question does not have an easy answer, unfortunately! The Latin word 'alba' and its relative 'album' means white. Horticulturally speaking, most of times it is used to designate white flowers, but this is not mandatory. For example, James Veitchi described Laelia purpurata var. alba, which in fact was not an alba, but a flower that had white sepals and petals and pink lip. On the other hand, take Cattleya mossiae var. wageneri and you will see that it is a white flower. But, this is not all. many call alba the xanthic (green with white lips only) varieties of flowers like Cattleya guttata, C. granulosa, C. forbesii etc.
I'm rising this just to say that naming orchids and especially naming varieties has no rule at all and the usage of the word 'alba' is no exception.
Anyway, in general, especially in the Cattleya alliance, a flower is considered an alba if it is white, but yellow in the throat and/or small amounts of green in the sepals tips, or at their bases are tolerable. In this alliance, the yellow in the throat is so common that in case the flower does not present that yellow it is called 'alba plena' (plena = completely). Alba plena varieties are very rare flowers in this alliance.
Hope that helps.

[RosieC]

Thanks Mauro,

So really it comes down to what the original person who described and named the species/variaty decided was 'alba'.

It's interesting about the yellow being very common in the albas of the Cattleya alliance. I love how much I learn all the time on OB