Blue Orchids

[Andrew]

There are some good blues within the Thelymitra and Cyanicula genera. Some of the line bred Vanda coerulea's are also a reasonable blue. The blue colour in Australian genera such as Thelymitra at least appears to result from the anthocyanin cyanidin (the same pigment that makes cornflower blue).

The idea of a blue gene is a bit miseading. The blue pigment in plants can be produced by a several of types anthocyanins, the same chemicals that produce red pigments in plants. Hydroxylation and dehydroxylation of anthocyanins shifts their colour between red and blue in the presence of certain cofactors. Thus lack of blue flowers in nature does not necessarily represent the lack of a blue gene in non-blue plants but rather the difficulty in getting plant cells to drive the hydroxylation of anthocyanins into their blue state.

[Undergrounder]

Thanks Andrew very interesting!

I think some of you guys are being very 'blueist'.. I've seen plenty of orchids that i would call 'blue', not 'purple'...

[snow]

how about the himmalayan poppy?
if thats not blue, i don,t know what is.

[snow]

hydrangia.

[greenbean]

Yes those are very blue, and Himalayan blue poppy is one of my favorites, but they aren't orchids. True blue orchids are very rare, so I agree that we should be happy with the "blues" that orchids do have. Personally, I love some of the blue vandas, and Neostylis Lou Sneary 'Blue Moon', if only for the name, as it's certainly not blue, and the fragrance. Now if only I could find one!

[dgenovese1]

Jorge,

While I can't add anything to this discussion, I appreciate that you brought it up. I have enjoyed reading the entire post.

[Andrew]

I grow a number of Thelymitra and I have a number of species with varying shades of blue flowers. I always find it somewhat ironic that, while people dream of growing 'blue' orchids, I prefer the yellow Thelymitras.

[DebsC]

This might help a bit;

APPEARANCE

The frequent use of the term “blue Cattleya” notwithstanding, the flowers of variety coerulea Cattleyas are a color that is nowhere near the primary color blue the name suggests. The reason coerulea Cattleyas are referred to as blue is the bluer than is normal color of the flowers. The flower color of "blue" Cattleyas varies widely from cross to cross and may even vary considerably between orchids from the same clone. The color can be anything from an attractive shade of pink or pink-mauve to rich shades of purple-blue. AOS judges describe “blue” Cattleyas use a variety of descriptive colors such as lilac, rose blue, blue-lavender, lavender-blue, blue-violet, blue-purple or indigo blue. From these names, it should be apparent that most 'blue' cattleyas have a considerable amount of red in the flower color giving most 'blue' cattleyeas a color that is best descibed as a bluish shade of purple.


ORIGIN
Blue flower color is rare in orchids, and very rare in Cattleyas growing in their natural range. While growing in the natural range, "blue" Cattleya are the result of extremely infrequent mutations producing a plant that is typically called "variety coerulea" Many Cattleya species have coerulea color forms, though some species such as the yellow flowered Cattleya dowiana either doesn’t have a coerulea form due to the yellow original color or the coerulea form is extremely rare.

CHEMESTRY AND GENETICS
In orchids, the range of colors possible for a flower is defined by a complex of anthocyanin and co-pigments within the cells of the flower while the actual color expressed is determined to a great extent by the floral pH. The blue color in many orchid flowers is known to be associated with an alkaline floral pH. Research on some blue orchid blue forms has sown that blue color increases as the floral pH becomes more alkaline. Experiments with the blue form of Phalaenopsis pulcherrima show that the pH resulting in the blue form of the flower is inherited in the ratios expected for as a single recessive gene. [1]

ENVIRONMENTAL FACTORS
Blue Cattleya breeding expert Ervin Granier has conducted research which shows that the expression of coerulea coloration is very dependent on plant nutrition in at least the Cattleya alliance orchids he tested. His findings showed that the lack of a certain nutrient may suppress the expression of coerulea coloration significantly.. Fortunately, he says, most commonly used fertilizers such as Peters or Miracle Grow contain just enough of the nutrient to assure the full development of coerulea color. Adding more of the nutrient doesn't make flowers any bluer.


[1] Robert J. Griesbach, PhD, Breeding for Blue Flowers, Orchids, May 2005 (Volume 74, Number5)

[sucuz]

Thanks for the article, Debs. Very interesting. Too bad that you can't play with the acid/akaline balance or with nutrient levels to bring out the blue like with hydrangeas. Oh well...guess that orchid colors are what they choose to be for themselves. We can tinker, but there are limits. Just one of the reasons that we love them so much.

[Mel]

Andy's Orchids - Orchid Species - Cleisocentron - merillianum

I have seen this one in bloom. The blue is an aquamarine.

some people on the board here have bought it.