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The Good, The Bad and The Stinky
A Profile of Orchids and Their Myriad Fragrances
By Christopher Croom
Photo: Rachel Cobb
The family Orchidaceae contains the largest number of named flowering plants, with at least 25,000 species. There are literally millions of cultivated hybrids and hundreds of natural hybrids, with the former being created by orchid hybridizers and hobbyists, and the latter being created by pollinators occurring in the orchids’ natural habitats. Some experts believe that as orchid taxonomy continues, there may eventually be as many as 30,000 to 50,000 naturally-occurring named species, meaning that there are up to 100 percent more species that haven’t even been discovered yet.
Orchids are one of the three most popular cultivated flowers in North America, with the Phalaenopsis genus and its related hybrids being the most often sold and grown. Orchids are commonly considered to be “exotic” tropical flowers, inhabiting steamy, equatorial jungles in horticultural conditions considered difficult or nearly impossible to emulate in captivity; this is largely a myth. As the largest family of flowering plants, they occupy every continent except Antarctica, and many thrive outdoors in California. The state flower of Minnesota (yes, Minnesota, with winter temperatures that often reach -40 degrees Fahrenheit with eight or nine months of snow on the ground) is an orchid known as the “showy ladies slipper,” Cypripedium reginae.
Orchids are everywhere, from cultured beauties sold in big box stores (think Target and Home Depot), to natives growing in state parks. California has over 20 wild orchid species that can be regularly found, including a newly re-identified species from Yosemite. Platanthera yosemitensis, which smells like sweaty gym socks. A handful of native species can be found in San Diego County, including Epipactis gigantea, the “stream orchid,” often found in or near streams.
Orchids are both exotic and startlingly familiar at the same time, which is part of the mystique of the plants themselves. And, their fragrances are just as enigmatic. About 85 percent of orchids produce a fragrance of some kind, but often their fragrances are produced for their pollinators, rather than our human noses. Orchids produce scents though structures called “osmophores,” which typically resemble tiny hairs with dots of aromatic oils on the ends of them. (Some orchids produce hair-like structures on their flowers that don’t provide volatile oils). These osmophores release their aromatics at certain temperatures and particular times of day, tailored to attract their wild pollinators when they’re likely to be active. That’s why some orchids are exclusively night-fragrant, others are only fragrant during the day and some species have stronger fragrances at dawn and dusk.
So, whether an orchid flower is “fragrant” has to do more with the time of day you are smelling the flower and your ability to detect its fragrance. Pollinating fauna have different abilities to smell flowers than humans often do.
These complications are magnified by orchid hybridizers who typically breed orchids for their flower size and color combinations, rather than their fragrances. This is important, since 98 percent or more of the orchids you are likely to encounter in garden shops will be hybrids. This means that unless you go to someone who grows orchid species in particular, you’re probably not going to find orchids with the wealth of fragrances that are truly represented by the orchid kingdom. No worries, though, the largest orchid species
grower in the world, Andy’s Orchids (www.andysorchids.com), lives and sells plants out of his greenhouses in Encinitas.
Luckily, even though the orchids at regular garden shops are not bred for their fragrances, many of them are still fragrant, and delightfully so. Cymbidiums, for example, are cold-tolerant (at temperatures above freezing), have large, waxy, long-lasting blooms and often have hints of lemons or oranges in their bouquets. Not only can your cymbidium handle the same basic cultural requirements as a rose (minus the pruning, and grown in medium or fine fir bark instead of dirt), but it has flowers that can last up to two months each. And, established plants have flowers that can get five or six inches across.
Cymbidiums are the more stately orchids you’re likely to find at places like Trader Joe’s and big box stores, with fist-sized or larger ovoid pseudobulbs at the level of the substrate, and long, strap-shaped leaves that up to two or three feet in length.
Cymbidium flower colors range from light and dark greens, through pastel and bright yellows, oranges, reddish-browns and pinks. They may or may not have spots on the “lip,” one of the structures that you’ll notice first when looking at an orchid. The lip looks like a petal with completely different decoration and form than the others. It is typically larger than the other petals, and pointed downwards in resupinate orchids like cymbidiums. This is also where the osmophores or “scent glands” are most likely to be found. Some cymbidium flowers smell like grass or lettuce, so when it comes to these impressive orchids, you should probably smell the hybrids before you buy them.
Species cymbidiums, on the other hand, are likely to have more consistent fragrances from one plant to the next. Some cymbidium species will smell like oranges, and others like gardenias and the finest perfumes (in particular the compact Chinese species like C. goerngii, C. sinense, C. kanran and C. ensifolium).
Another fragrant orchid species you’re likely to come across on a regular basis at garden shops is the Cattleya, or hybrids involving this orchid. Cattleyas have showy blooms that typically last about two weeks, and are often five inches across or more with ruffled edges. Many of you probably wore cattleya corsages and boutonnieres to your proms, and Cattleya orchids reached the height of their popularity in the 1950s and early ‘60s. Since that time, these big and fragrant flowers have been hybridized with members of the Laelia and Brassovola genera to produce larger, more symmetrical, and sometimes more fragrant, blooms. While cattleyas don’t last as long as cymbidium flowers, they are supremely and delightfully more fragrant, loaded with osmophores and often smell as good at night as they do during the day.
They are equally easy to grow, requiring about the same bright light levels as cymbidiums, but they like to dry out between waterings a bit more and therefore need to be planted in coarse fir bark mixtures. Cattleyas won’t necessarily all grow outside year-round in our climate like the large cymbidiums will, either, so you have to be careful about your selection.
You’re likely to do well with intergeneric cattleya hybrids with the abbreviations “Lc.” (Laeliocattleya) or “Slc.” (Sophrolaeliocattleya). The latter won’t be as fragrant, but are likely to have flowers with more red in them. A good fragrant cattleya should smell like the most overpoweringly intoxicating flower you’ve ever whiffed, with hints of the best floral notes you could possibly imagine, from frangipani to gardenia to honeysuckle, all rolled into one. Take care, some might smell somewhat medicinal.
Oncidium ‘Sherry Baby’
Photo: lucy Warren
The last of the fragrant orchids that you’ll be likely to encounter in a garden store environment will probably be Oncidium ‘Sherry Baby,’ which has many awarded cultivars that might appear in single quotes after this part of the name. ‘Sherry Baby’ is probably the most popular orchid with a fragrance that we can detect, if only because it is known as “the orchid that smells like chocolate.”
‘Sherry Baby’ is easy to grow outdoors, year-round in areas that don’t freeze, either mounted on a tree with moss wrapped around the roots or in a pot with fine or medium fir bark. It has starry, usually deep reddish-brown flowers that have been grown larger and larger over the years with improved breeding, blush purple/pink lips with a whitish callus in the center. It has a very sweet aroma with strong hints of vanilla and something else that is hard to characterize, but is nonetheless extremely pleasant. Vanilla is an ingredient in chocolate (and is an orchid itself), and one of the species parent plants of ‘Sherry Baby’ (O. ornithorhynchum) smells like vanilla mixed with chardonnay. Thus ‘Sherry Baby’s’ fragrant reputation comes from the famous chocolate-like aroma might be attributed to its parent for the sweetness mixed with slight hints of astringency, the strong vanilla overtones in the fragrance and the chocolaty appearance of the blooms. Non-orchid hobbyists are typically unaware of how prevalent this plant is in cultivation and how easy it is to grow. It’s tough, tends to grow like a weed when compared to other orchids and is very difficult to kill. Some hobbyists can even get it to bloom more than once a year.
“So, where’s the ‘bad’ and the ‘stinky’?” you might ask, as I’ve only described orchids with delightful fragrances, or that are neutral, at worst, so far. Species orchids have fragrances that range from the most pleasant jasmine and gardenias, through roses, primroses, tuberoses, violets, narcissus, paperwhites, hyacinth and anything pleasant in the floral world you could imagine. On the other hand, orchids may also have flowers that smell like every rank cleaning product imaginable, horribly bitter medicines or industrial toxins. Orchids can often smell like fresh or rotten fruits, ambrosial candies, feet, aged cheeses, animal excrement or even dead bodies. Some smell like cut green bell peppers, like Cycnoches barthorium, and some like fresh peaches, such as Dendrobium unicum. Some smell like my grandma’s perfume, such as Dendrobium chrysotoxum, or a mixture of wine and perfume, such as Dichaea glauca. Some have more complex odors, such as Stanhopea tigrina, which smells like an overpowering combination of vanilla, mint and chocolate. Many orchids have green apple fragrances, such as Dockrillia pugioniformis, Sarcochilus fitzgeraldii, Epidendrum raniferum, and Sarcochilus hartmanii. Some even smell like honey, like Prosthechea cochleata (the national flower of Belize), Prosthechea chimborazoensis, and Dendrobium macrophyllum. Others are reminiscent of candy, such as Neofinetia falcata, the “samurai orchid,” which has been cultivated for a thousand years or more in Japan. Many smell like cinnamon or freshly-baked apple pies, like the yellow-flowered Mexican Lycastes, both Meiracyllium species or about a dozen or more members of the genus Prosthechea that are found in Central and northern South America.
Yet some orchids smell like the musk glands of animals (some individuals of Coelogyne ochracea), or even the treats your dog leaves for you in the backyard, like Bulbophyllum echinolabium. Just a couple of weeks ago I was at Andy’s Orchids and smelled a Bulbophyllum orientale flower that smelled of rotten apple cores and banana peels. Some orchids smell like the skin of a fish or pond scum—like Ancistrochilus rothschildianus or Bulbophyllum psychoon or Gastrochilus calceolaris. Bulbophyllum carunculatum and Masdevallia caesia both smell like rotten brie. Bulbophyllum fascinator smells exactly like boiled crab, which is a pleasant smell in itself, but disconcerting when worn on a flower.
Many of these plants have hauntingly beautiful or proportionately large flowers—the bloom on B. echinolabium can grow to 16 inches or more on a plant that would fit in a 10" or 12" pot! Unfortunately, all of these italicized plants are species orchids, have no accurate common names and are not something you’re likely to run across unless you go out of your way and find a local grower.
So, how do you experience the myriad of fragrances that orchids have to offer? Purchasing cattleyas would be a great place to start, but you might want to join your local orchid society so that you can make sure you know what a Cattleya is first. The San Diego County Orchid Society (www.sdorchids.com) is one of the largest orchid societies on the West Coast, and its members will gladly show you to the cattleyas.
Photo: Rachel Cobb
Reprinted from March/April 2008, Volume 99, Number 2
Mission: To promote the knowledge and appreciation of horticulture and floriculture in the San Diego region.