Searching for Orchids with Flowers Offering this Coveted Hue

OF ALL THE RAINBOW’S COLORS, blue is perhaps the least represented in the plant world. If you think about it, flowers of a true blue hue are a rarity, and this is applicable to the orchid family as well. Still, there are orchid species, varieties and hybrids that are called “blue” and they are found in various branches of the orchid family. For the most part, their flowers have colors that tend toward bluish shades of lavender, lilac or violet. Technically, these are more properly termed forma (fma.), or forms, rather than variety, since they represent aberrant clones, as with white forms, which are referred to as alba. 

The example of the blue cattleyas is a good place to begin. It is not hard to understand why the quest for a blue flowered example of this most popular orchid captivated the hybridizers’ imaginations almost from the start. 
I still remember the first time that a blue cattleya flower was shown to me. The coloration was unquestionably unique and indeed, somewhat in-triguing, but I could not help but think to myself, “They call this blue? Who are they kidding?”

CATTLEYAS  But to be fair, the species of the Cattleya alliance simply do not possess the pigmentation necessary to produce really blue flowers. At best, most of the blue cattleyas are rather pastel shades of a color I would call gray-violet, a hue that is not only difficult to describe, but one that can also be a challenge to accurately capture on film.

Yet a number of Cattleya species are known to have or have had these blue forms, which are usually termed coerulea varieties. Cattleya labiata, Cattleya gaskelliana, Cattleya walk-eriana, Cattleya mossiae and Cattleya bowringiana are but a few. Typically, the word coerulea, meaning blue, is used in the subspecific epithet to designate the blue varieties of the species. Two examples are C.  gaskelliana var. coerulea ‘Drago’, HCC/AOS, and C. walkeriana var. coerulea ‘Monte Azul’, AM/AOS.
Dedicated hybridizers have been crossing the coerulea varieties of the Cattleya species and have been working with their hybrids for more than a century in an attempt to improve their color and form. The results have been somewhat mixed. Perhaps that is because most coerulea varieties tend to lack in size, form and substance when compared to their more typically colored brethren.

Still, with better color likely the main goal, hybridizers have successfully intensified the coerulea hue and that color is often accented by darker tones in the lip. Cattleya Ariel (bowringiana × gaskelliana) is a primary hybrid that dates to 1915. While it is virtually certain that the original cross was not made with blue varieties, such were subsequently crossed and produced the cultivar ‘Bodnant’ that features good coerulea color. Taking this breeding a step further is Cattleya Sapphire ‘Sea God’ (Ariel × labiata), which was registered in 1968.

Later efforts are represented by Brassolaeliocattleya Lois McNeil ‘Gran Stan’, HCC/AOS. The grex was registered in 1983 and offers rather good, strong color. Its somewhat complex breeding is based primarily on combinations tracing to C. labiata and C. bowringiana. Brassolaeliocattleya Boy’s Grotto (Lc. Blue Boy × Blc. Blue Grotto) has been around about 10 years. It is another good coerulea grex with a considerably more complex heritage that relies on contributions from seven species in the Cattleya Alliance. There is no doubt that the blue cattleyas continue to intrigue those who admire them and there are those hobbyists who specialize in collecting and growing them.

DENDROBIUMS  The genus Dendrobium is another good place to look if you are seeking orchids with bluish flowers. The species Dendrobium victoria-reginae is one that immediately comes to mind. There are also a number of hybrid dendrobiums, often of the Dendrobium nobile type that have flowers with coerulea tones. Dendrobium Blue Sparkle and Dendrobium Blue Twinkle are but two,and I had a hybrid of these that was nicely colored and a vigorous grower as well.

SPECIES TO TRY  Species col-lectors looking for blue flowers can seek out Bollea coelestis, a native of Colombia. It produces quite showy solitary flowers up to 3 or 4 inches (7.5 or 10 cm) across. Acacallis cyanea, from Brazil, reputedly has rather true blue flowers, but I have no experience with it. It is related to the genus Zygopetalum, which is another good source of bluish and violet-colored orchid blossoms. Zygopetalum mackayi has flowers with lips streaked a purplish-blue, while some of the hybrid zygopetalums feature even more saturated blue color.

VANDAS  The Vanda alliance is perhaps the best source of blue orchid species and hybrids too. Rhynchostylis coelestis is a species that can produce spectacular inflorescences composed of numerous small flowers in a foxtail arrangement. One of the prettiest blue orchid hybrids I have grown is also a Vanda relative, Darwinara Charm ‘Blue Pacific’ (Neofineta falcata × Vascostylis Tham Yuen Hae). 

In fact, the Vanda Alliance includes some of the bluest orchid species and hybrids that are commonly available. Vanda coerulea, from India, has flowers that range in color from rather pale blue to dark slate-blue. It has parented and contributed to the pedigrees of numerous Vanda and Ascocenda hybrids with flowers of some incredibly blue shades. Ascocenda Princess Mikasa (Royal Sapphire × Vanda coerulea) is but one example.

The bluest orchids I have seen were actually shown on slides during a presentation by the speaker at our local orchid society recently. They were the flowers of Disa longicornu, which are colored an almost unnatural light sky blue. It is a relative of the more familiar crimson species Disa uniflora. Both are terrestrial plants that may be found growing on Table Mountain above Cape Town, South Africa. The genus Disa indeed includes some species with flowers of remarkably intense coloration, but unfortunately, their cultural requirements make them unsuitable for the average grower. 

I was surprised to learn of that one, which was previously unknown to me. It was a reminder of the orchid family’s size and diversity. There are other blue flowered orchids that I have seen referenced in books and magazines as well, so I think it is safe to say that those with a penchant for the blues should always be able to look to their orchid collections for a bit of happiness.