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The Family of Orchids by Aaron J. Hicks With MANY thanks to: Bruce Ide (American Orchid Society) Rod Venger (Venger's Orchids) No group of plants has been more deeply immersed in lore and fiction than those of the orchids; black orchids and wild orchids, from Nero Wolfe to Charles Darwin, no single group of flower can lay claim to the mystique that orchids have, and still do. Of some 650 recognized genera of orchids, only 100 or so are commonly brought into cultivation; the neophyte will be introduced to a handful of this amount, possibly a dozen or so at the most. The single greatest fallacy of orchid culture is that they are incredibly difficult to grow; to the contrary, the majority of the species and hybrids that are commercially available are quite easy to raise, given the proper set of conditions. It has been said before that if one can raise African Violets, that you can raise orchids as well. As a matter of fact, the entire family of orchids is remarkably adaptable to home conditions; I have personally seen orchids raised in all environs, from steamy hothouses, to collections intermixed with cacti and succulents. The best rule of thumb to remember is that orchids are remarkably varied; given all the hybrids and species on the market, one is likely to be able to find a number of plants suitable to your own specific growing conditions. And how does one best accomplish this? Most dealers are very supportive of new growers, and can help by guiding you to plants that are more readily cultured. Of course, any guidelines such as "Easy to grow" should be taken from the same perspective as one would take for any other plant- the division off of that Iris in your yard, for example, that grows like a weed died the minute your neighbor put their hands on it. With this in mind, there are three primary temperature groups that orchids tend to fall into- cold, warm and intermediate growers. People in the southwest will have difficulty growing cool-growing Miltonias, and people in Minnesota will be distressed by their heating bills should they decide to raise Phalaenopsis by the hundreds. Rough guidelines are given with the culture section to follow. This FAQ is not designed to turn someone who has had a single plant with a tattered and faded label thrust into their care into a world-class culturist; there is only one thing that can do that, and that is experience. Experience with orchids comes primarily in one form: killing them. For every experienced orchid grower comes a price other than that which is on the tag, and that is killing orchids. Many are not particularly finicky plants, but it may simply be your current horticultural conditions that caused that case of black rot, or dehydrated the plant, or something else that caused an awful fate to befall your once-robust specimen. So beware! the "expert" in orchids who claims they never killed a plant- they are not telling the truth.... 1) Technical background The family Orchidacea is comprised of (approximately) 650 genera, with an estimated 25,000 to 35,000 species. They are found on every continent excepting Antarctica. Estimates of the number of hybrids extends into the 200,000 mark. The bulk of the species that are brought into cultivation are tropical and epiphytic, although many types are terrestrial in nature, and there are orchids native to virtually every portion of the globe. Their epiphytic nature (meaning that they grow primarily upon other plants) presented a great problem to early would-be orchidphiles. Despite great protest from the adventurers who brought them back, culturists insisted on plunging them into barrels of sawdust that were in overheated growing rooms nearly saturated with water; this assured killing the plant in very short order, both by smothering the roots and through rot. Today, it is widely recognized that the epiphytic species live attached to branches of immense tropical trees, adhesed to the massive branches through tough roots. They are bathed constantly in moving air, and in many areas, the primary source of water is from morning dew, rather than rain. It is in this environment, with bromeliads and tropical ferns, that these plants thrive- subsisting on little nutrient content than what is supplied by bird droppings, and by tiny bits of tree bark trapped between their roots. 2) Cultural In culture, these conditions are simulated to the best of our ability by providing the roots of a potted specimen with as much air as possible (for the majority of cultured plants), by using highly porous media, and by keeping the plants themselves in conditions similar to those they are naturally from, by moderating their water sources, and preventing stagnant air. Another technique for growing orchids is to "plaque" them, which entails wiring a plant to a slab of cork, osmunda or other suitable growing media, and then allowing the plant to grow onto it in the same manner as they would do so in the wild; these plants do best under conditions that have considerably higher humidity than that which is seen in most homes, as the roots are not kept as moist for as long as they are in a pot. For most greenhouses, they are very acceptable. Water: water, as orchids receive it in nature, is generally nearly as pure as distilled water. As such, it makes tap water look more like mineral sludge. Oddly, even in areas with generally very hard water, this does not provide much of a problem, unless these salts are not flushed from the pot with copious quantities of water periodically. Of course, babying your plants with either distilled or reverse osmosis (RO) water may help you prevent this. Should heavy white crusts appear on the media you are culturing your plants in, be certain to periodically flush the pot (i.e., whenever you water) with copious quantities of water- at least until there is considerable water coming out of the drain holes. Care, in this sense, is not that much different than that of most other house plants: excess salts will dehydrate the roots, through osmosis, and eventually damage or kill the plant. Fortunately, this takes considerable time, and is generally quite reversible until serious damage occurs. The best rule for watering orchids: whenever they need it. Plants like Cattleyas and Phalaenopsis require that the media dries out (perferably not bone-dry) between waterings; this keeps the roots from rotting and, if you are using an organic media, keeps the media from rotting. It also helps discourage insects and other plant pests. If in doubt as to whether or not to water: don't. Withholding water will rarely kill these plants (exceptions: Paphiopedilums and Phragmipediums, whose roots need to be moist -not soaking- or they can be damaged. Also plaqued plants, which should be misted regularly, especially when humidity is low, for reasons already mentioned). Watering should be performed as early in the day as possible, which allows for water accidentally splashed on the leaves to evaporate, as this may cause rot if allowed to remain for a period of time. Try not to spill water into the crowns of sensitive plants, such as Phalaenopsis and Paphiopedilums. Fertilizing: Keep in mind these are plants that normally live off of decaying bark and bird droppings; the former is one of the reasons that I use primarily organic mixes. As the mix breaks down, it supplies certain concentrations of nutrients. Supplimentation is best provided through the use of any water-soluble fertilizer, although most orchid growers that have access to it, use Peter's for Orchids, which is 30-10-10, and has extra iron added. On the other hand, virtually any 10-10-10 or 20-20-20 will do; use half the recommended quantity, and use it with less frequency than is recommended on the label. How often you should apply it depends upon how actively the plant is growing, how often you are watering it, and how big your pots are (and, therefore, how long it takes for them to dry out). Some growers also use Superthrive, at either recommended, or reduced, concentration. Humidity: humidity for optimal growth of orchids is approximately 50% to 80%, but this can be dropped if the plant has exceptional root systems, or is of a type that does not respond negatively to low humidity (I have found a number of Mexican species do well in low humidity, for example). Should humidity rise much above 75%, it is suggested that air circulation should be increased. Orchids do well in kitchens, over the sink, or in the bathroom. Air circulation: as orchids normally live in the tops of trees, bathed in air, they tend to do better, especially when they are in larger collections, when the quantity of air circulation is maintained at a high rate. This may be established by providing your growing area with an osciallating fan or two. Most commercial greenhouses maintain a high rate of air circulation for their plants; water that pools in and on plants will tend to evaporate more readily in a light breeze than they normally would, which will help prevent rot and decay of plants. The media: Oh, BOY. Where do we start here... Orchids may be potted in one of a variety of media, including redwood or fir bark, tree fern fiber, charcoal, osmunda (the dried roots of the Osmunda fern), coconut fiber, pumice, lava rock, sphagnum moss, singly or in any combination of these compounds, and many, many more. A bit of advice: until you learn what works best for YOU under YOUR growing conditions, do not make radcial changes. The author personally knows of one grower who, after going to a lecture on how WONDERFUL lava rock was for HIS plants, thought it would be a good idea to rip up all of his plants, and plunge them into lava rock. They all died, as lava rock was not good for his conditions. Unless otherwise noted, fir bark seems to be best for most of the epiphytic species of orchids that the novice will encounter. It is inexpensive, easy to work with, and readily available. For Phalaenopsis, I personally perfer a mix that holds water a bit better than bark, so I use a combination of sphagnum moss, a bit of bark, a bit of cork, some perlite and charcoal. With Cattleyas, most any mix will work. With Paphs and Phrags, although fir bark has been used (with or without vermiculite), I prefer a mix that holds considerably more water; one trick I have been introduced to is to use chunks of foam rubber, about 1/4S cubes (as much as you can make a cube with foam rubber and a pair of scissors), which seems to "breathe" well. Do NOT go immediately into "exotic" mixes that people "swear by", unless they have traditional components in them; again, they may work well for someone else, but your growing conditions are most probably very different. A popular source for orchid growing mixes: OFE International, Inc. P.O. Box 164402 Miami, FL 33116 (305) 253-7080 Pots: as orchid roots like air, the more ventilation, the better. A small handful of styrofoam chips, placed in the bottom of the pot, make for better ventilation. With HUGE plants, inverting a smaller pot in the center of the bottom of the larger pot when repoting greatly increases the quantity of air that reaches the roots; as orchid root systems may be rather small in the center of such large plants, this will not hurt them. It also makes the pot considerably lighter, and keeps the center of the pot, media and roots, from rotting. When potting orchids, I generally use plastic, as the roots tend to come off of it better when repotting next time, and is lighter than plastic. It is also more readily broken without harming the plant, should the plant grow into the pot to a degree where this becomes necessary. How to repot orchids is an art more than a science; most of it depends upon telling when a plant should be repotted. First rule: never repot a dormant plant. Spring is the best time; Cattleya types should have new growths about 2-3" long, and roots starting to appear at the base of the growth. Phals should not be in spike, and should be actively growing. Generally, orchids only need to be repotted for two reasons: they are coming out of the pot, or the media is rotting out from under them. If you have a Cattleya or a Dendrobium where there are new growths RhangingS in mid-air, outside of the pot, it is time to repot. If the media, when you dig down a bit, is black and mushy, it is time to repot. Most of all, don't be pot-happy: most orchids like a *tiny* bit of restriction, and many can stay in pots for several years (4-5 years, up to 8). Pots should be sterilized first: clay by baking them, or plastic by soaking them in 10% Chlorox for 1 hour or more. Wash well before potting, of course, just like your hands. Take the plant to be repotted, and remove all the media possible. Invert the pot, and remove the plant as best as possible (yes, you probably will tear roots; do not touch open orchid wounds, to prevent accidental viral infection). Remove all old media, and discard; do NOT use this for potting another plant, as the old plant may be virused, and could infect another plant. Place it in the cleaned pot, which should be sized appropriately to allow for growth. With Cattleyas that have a "line" of growth, give the plant plenty of room in the direction that the new growth is heading; this is to say, you can even "push" it into the corner of the pot opposite that of the new growth. Fill in with the media of your choice, and tamp and settle it. Cumbersome plants may need staking or other support. Should you require support, I suggest calling a friend. :-) Additional cultural information can be had from: The American Orchid Society 6000 South Olive Avenue West Palm Beach, FL 33405 They produce the American Orchid Society Bulletin, which is published monthly, lavishly illustrated with color photographs of orchids, and dedicates a good portion of their periodical to advertisements, which will allow you to expand your collection. Caution: orchids are habit forming! The AOS Bulletin is NOT a rinky-dink publication! The AOS is also the governing body behind judging the quality of plants. The primary scheme goes something like this: FCC/AOS: First Class Certificate, American Orchid Society. This is the highest award an orchid can receive under the AOS. Precious few are awarded each year. AM/AOS: Award of Merit, AOS. This is the second-highest award granted by the AOS. Several are granted each year. HCC/AOS: Horticultural Certificate of Commendation, AOS. Third-highest award under the system of judging.
Although an FCC will most likely be quite expensive for a period of time after it is awarded, eventually such popularity wanes, and plants can be had for considerably less after this period. Replacing AOS with RHS means the award was granted by the prestigous Royal Horticultural Society, which has some different awards, but are no less scrupulous in their granting of awards. A list of types of awards,as granted by the American Orchid Society (from The Handbook on Orchid Nomenclature and Registration): AD Award of Distinction AGM Award of Garden Merit AM Award of Merit AQ Award of Quality BA Bronze Award BC Botanical Certificate BM Bronze Medal BMC Bronze Medal Certificate BRC Bronze Certificate CBM Certificate of Botanical Merit CBR Certificate of Botanical Recognition CC Certificate of Cultural Commendation CCM Certificate of Cultural Merit CHM Certificate of Horticultural Merit CPC Certificate of Preliminary Commendation FCC First Class Certificate FCD First Class Diploma GC Gold Certificate GM Gold Medal GMC Gold Medal Certificate HCC Highly Commended Certificate JC Judges Commendation PC Preliminary Commendation RHC Rare Hybrid Certificate SC Silver Certificate SM Silver Medal SMC Silver Medal Certificate SMM Silver Medal of Merit A partial list of the RHS awards: RHS Awards FCC= First Class Certificate AM= Award of Merit CCC= Certificate of Cultural Commendation PC= Certificate of Preliminary Commendation It is highly recommended that the reader subscribe to the AOS Bulletin; it is a first-class journal, bursting with articles on technique, on culture, and on the latest in orchid science and politics.
There are several "subfamilies" of orchids, and, with notable exceptions, the rules are fairly similar. First, a word on native species of orchids. Native species of orchids are beautiful. It has been asked many times, where they can be purchased, how they transplant, the best ways to cultivate them and so forth. The basic rule is this: unless you have them growing on your property already, you will not be able to culture native American orchids. The reason is fairly simple: in the wild, orchids require the presence of a special mycorrhyzial fungus that lives in symbiosis with the plant. The plant provides a home, the fungus provides compounds for the plant to thrive. When transplanted, the roots are shocked tremendously, and this may disrupt, or even kill, the fungus. The plant may come up weakly the first year, more weakly the second, and probably not at all the third: the plant will probably not flower at all. Even if a significant portion of the root system is taken with the plant, and the trauma is kept to a minimum, it is unlikely that the soil in your backyard is amenable to growing native species of orchids (thus, the comment that "unless you have them growing on your property already..."), as many of these species are very sensitive to soil types. Many of these plants that are offered for sale have virtually no roots on them, and perish without ever coming up. Many are removed from public lands illegally, and those that are taken from private lands with permission are indistinguishable from those that are not. As a result, the sales of these plants assists, with very little variation, in the extinction of these species, and the corruption of our public lands. Do not purchase native species of orchids. It should also be noted that the techniques that are commonly employed for propagation of tropical species of orchids by seed and by cloning are not well-established for these species, and probably will not be without a major economic motivational force, which is highly unlikely.
3) The Plants
Orchids are unusual in that they form intergenetic hybrids, most of which are fertile (in contrast to infertile progeny, or genetic "mules"). There are literally hundreds of orchid genera, both naturally occuring, and as artificial hybrids. Thus, when we take a Brassvola and cross it onto or with a Cattleya, we produce the artificial genus Brassocattleya, which is abbreviated Bc, as you can see below. With more complex hybrids, they are commonly named after individuals in their honor, or after the company that sponsored the work (See Potinara, below). Some helpful abbreviations and their parentage: Bc. - Cattleya type (Brassocattleya = Brassovola X Cattleya) Blc. - Cattleya type (Brassolaeliocattleya = Brassovola X Laelia X Cattleya) Cat. or C. - Cattleya Cym. - Cymbidium Dend. - Dendrobium Enc. - Encyclia Epi. - Epidendrum L. - Laelia Milt. - Miltonia Odont. - Odontoglossum Onc. - Oncidium Paph. - Paphiopedilum Phal. - Phalaenopsis Pot. - Potinara (Brassovola X Laelia X Cattleya X Sophronitis) Sc. - Sophrocattleya (Sophronitis X Cattleya) Slc. - Sophrolaeliocattleya (Sophronitis X Laelia X Cattleya) I have arranged these in no particular order.
Genus Phalaenopsis: The Moth Orchid Probably one of the most commonly purchased orchid is the Phalaenopsis. They are fairly easy to culture, easy to bloom, and very attractive and appealing flowers as a whole. There are large numbers of hybrids, many of which are well-suited to the novice. Species, although some are very attractive, may have flowers that will be somewhat smaller than the novice is looking for; hybrids are good to start with, or species, if one is certain they will like the appearance. The Rules: Phalaenopsis are warm growers. Generally, the temperatures should not drop below 60 degrees, and are best left with a minimum night temperature of 65. In order to bloom, on the other hand, they should have about two weeks of night temperatures into the mid-50's or so, and I have personally taken healthy plants down into 50 degrees with no damage. Phalaenopsis enjoy bright light, on the order of up to 1000 foot-candles in the summer, and even more in the winter (to about 1500 or even 2000 foot-candles). Phals will bloom whenever they feel like it, but generally do so in spring. A spike will form at the base, and elongate quite rapidly. After blooming, this spike may be removed, preferrably after it is dead and dried (see Pathogens, below). Phals grow in a monopodial growth pattern; they grow on a continuously lengthening upright stem, from which leaves sprout from in alternating directions. It is this center, or the crown, of the plant that is most susceptible to damage and rot; protect it by keeping moisture out of it, and drying it with a bit of tissue when it gets in. The fact that they are monopodial also brings about an unusual condition from time to time; the Phalaenopsis generally produces new roots just below the level of the base of the plant; as the plant grows larger, this point (where the roots emerge from) will extend further and further up. As new roots appear at this point, they may start growing well above the level of the media; under certain conditions of low humidity and high salts buildup, these roots may stop growing (the green tips will die), and the plant will start to dehydrate as old roots die off. This can be seen from new roots with dead tips, or that simply are not growing. The solution is simple: top-dressing. Unless the plant simply needs repotted, the base of the plant, where the new roots are emerging, must be surrounded with more media, preferably one that holds a great deal of water, such as dried sphagnum moss. The new roots will recieve more water, and do better. This is one reason Phals should be seated a little deeper (depending upon how much they have grown) into the media when repotted; make certain that the crown is well above the level of the media to help keep it dry, but also make certain that new roots will have access to plenty of water. Vandas are kissing cousins to Phalaenopsis: their culture is not advised for the complete orchid novice, and cultural information peculiar to this genus is best taken by the buyer from the grower. Cattleyas This group includes the genera Cattleya, Brassvola, Laelia and Epidendrum, as well as "odd-balls" like Sophronitis and Broughtonia, and many other plants from other groups. Look for the words "Care as for Cattleya types" or the like when using these cultural guidelines. Although the "traditional" corsage orchid has been largely replaced by flowers from hybrid Cymbidiums, at one point in time hybrid Cattleyas were virtually the only corsage orchid that one could purchase.
Most Cattleyas are quite easy to culture; they are happy under fairly broad conditions, in many different types of media, and it is not difficult to find a plant that will do well in a windowsill or kitchen. The Rules: Cattleyas are intermediate growers. Ideal night temperatures are between 55 and 60 degrees, although they can go lower without significant danger in the dormant stages. In the growing season during the day, temperatures are best around 72 to 78 degrees. The upper temperature limits are around 85 to 100 degrees, the latter being tolerated only for short periods of time, and out of direct sunlight. Cattleyas have a sympodial growth pattern, which means that the pseudobulbs (literally: false bulbs), which support the leaves, grow from a creeping stem or rhizome. The new leads are produced from the base of the previous growth, and when mature, produce a sheath and flowers from the center. This pattern may cause the plant to crane out of the pot, spilling out over the side (see "Repotting", above). In this manner, most standard- sized Cattleyas may grow one or two inches laterally per year. Flowering generally occurs with mature plant when the new growth has finished growing, and a thin green sheath sprouts from the center of the bulb; eventually, buds may form in it, which then proceede to grow and break out. Hygiene on Cattleyas is particularly important; as the pseudobulbs grow, they are sheathed in the smaller leaves that predecessed them. As the growth matures, these leaves then die, leaving a brown or white papery layer covering the pseudobulb. It is highly suggested that, after the leaves die, and the layer becomes dry and papery, that it be removed, either through peeling or carefully tugging it away (remember: only the dry dead stuff, please!) This serves two purposes. The first one is that the dry papery coating allows for a wonderful insect hatchery, and mealybugs wil commonly infest this dry haven if allowed. The second is that orchids will also photosynthesize through the green pseudobulbs if they are exposed, and this will make them more efficient in producing "food".
4) Propagation
The propagation of orchids by seed was a largely hit-and-miss proposition, entailing the dispersal of large quantities of orchid seed, and hoping that some of the seed would find an appropriate environment and germinate. Orchid seed is extremely tiny, on the order of millions per ounce. Counts can be as high as 1-3 million in a single seed pod set on a mature plant. Obviously, with such a large number of seed being produced, there is virtually no nutrients that are carried with the seed itself. It was in 1922 when Dr. Lewis Knudson developed a technique for germinating orchid seed on a large scale. His technique depended upon using nutrient agar media, sterilizing the seed through the application of chemicals, then sowing the seed on the nutrient media. Through the use of this technique, the method for propagating orchids was revolutionized, and remains the primary technique for propagating orchids today. This technique can be performed in the home setting, but is not recommended for anyone who is not willing to put in a fair amount of time and involvement. It is further suggested that, due to the number of orchid "mutts" that exist, that the only seed that should be sown is that which is gathered from reputable sources; if one is absolutely desirous that they must produce their own seed for their own purposes, only species should be used, with the pollen crossed back onto the same plant, or another specimen of the same species. Orchid hybridization is a science that takes a great deal of time and effort to learn, and few people have the patience to contend with the task. For example: in order to see the fruits of one's labor, from seed to bloom, a Phalaenopsis may take upwards of 5 years. Cattleyas can take into 7 or 8 years, and Vandas have a generation time of approximately 15 years. This is one of the reasons orchids are so expensive: a great deal of time and effort goes into producing a single plant. Along with that goes the skill and expertise of the hybridizer that "produced" the plant you just purchased. Even with species, commonly only the best cultivars are chosen to produce seedlings for sale to the public. One of the more popular sources for materials and information on sowing orchid seed is:
G & B Orchid Laboratory 2426 Cherimoya Drive Vista, CA 92084 619-727-2611
The other technique for propagating orchids on a large scale is meristem culture; from a single plant, literally thousands (or even more, if desired) of GENETICALLY IDENTICAL plants can be produced from a single plant. Thus, if you were to purchase a meristem of Cattleya Zebron Barr 'Trophic' FCC/AOS, you would receive a plant that was genetically identical to the plant that was awarded the FCC; obviously, hybrids will not produce such identical progeny. This technique is not readily performed in the home environment, but can be done with the addition of some equipment to that which would be found in a small seed sowing (or flasking) set-up; the actual procedure is beyond the scope of this FAQ.
For the home grower, propagation of orchids is primarily performed through division, or keikis. Orchids are divided when they become too cumbersome to satisfactorily remain inside a pot of a given size. Generally speaking, the division should have at least three back bulbs (old growths), preferably 4 or 5, and at least one new (actively growing) growth. The division should be made with a new, sterile razor blade: sterilizing is best performed by dipping in alcohol, then passing it through a flame. Do not re-use this blade for cutting live tissues on any other orchid plant, to keep down the spread of viruses. Take the division, and pot it up as you would any other seedling. With Paphiopedilums and Phragmipediums, the plants form clusters, and when divided, there should be no fewer than 2 larger plants, and 3 or 4 smaller plants in a clump. The larger the clump, the better; I personally do not divide either of these two types of plants, as I prefer the appearance of a large cluster of these terrestrial plants, grown into specimen plants. Phalaenopsis are somewhat recalcitrant to reproduce vegitatively; occasionally, one will produce a plantlet that will grow quite rapidly on a flowering spike, called a "keiki", which may be removed when adequate roots and leaves have been produced to assure its survival. Again, this only happens naturally on occasion; there are pastes available commercially that can be applied to nodes on the flowering spike to induce this artificially. Sometimes, rather than propagating plants that are already in collections, plants may be "imported" from the wild; some of these plants may be harvested from trees that have been cut down during slash and burn operations in the jungle, but many are not. Although "wild" plants may be very tempting to own or buy for the advancing novice, the rules are very simple: of the available orchid species, there are several variants, of which some are highly desirable. It is hoped that, in the process of propagating these, a hybridizer will use only the most appealing (in terms of flower size, ease of flowering, growth habitat, disease resistant, etc.) members of that species they have available. As such, if you go into a greenhouse, and look at two plants of the same species, one wild-collected, and one grown in the lab, there should be distinct differences: the lab-grown one will be healthier, look better, and probably have better flowers than the wild one. This is, quite simply, the goal of the breeder: to take a plant that exists not for the appeal of the culturist, and select those traits that make it more appealing. You will receive a better plant, in general, if you purchase one that has been propagated in the lab. Further, you will be saving those plants that exist in the wild from unscupulous collectors that decimate native populations.
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