Asahi image Copyright Evelyn Drew

Orchid Nomenclature

Orchid nomenclature can be intimidating to the beginner, but it is not that complicated. This article is intended to de-mystify orchid nomenclature, so that all orchid growers can understand the proper labeling of their plants, and the benefits derived therefrom. It is also an editorial on the danger of a new trend toward inadequate labeling of mass merchandised orchid plants.

What is Orchid Nomenclature?

Orchid nomenclature is based on the binomial system devised by the Swedish naturalist, Carl Linnaeus, in the eighteenth century. Using this system any plant can be succinctly described using two words: one for the genus, and one for the species, hence "bi-nomial." Prior to Linnaeus, plants were referred to using long descriptions that varied regionally, and similar to the common names used today, were rather ambiguous. The binomial system works because of certain conventions; for example, the genus must be unique across all plant families, and the species must be unique within a genus. The binomials are given in Latin, because when Linnaeus came up with this system, Latin was the language used by educated people in many countries, the language that people who spoke different tongues could use to communicate. Binomials continue to be given in Latin, because it trancends language and political differences.

In Linnaeus's system, the first word or genus, is a noun, and the second or species is an adjective describing the first. The two must agree in case and number; for example, Paphiopedilum philippinense and Phalaenopsis philippinensis, describing a Paphiopedilum and a Phalaenopsis, both from the Philippines. By convention, the genus is always capitalized, and the species is always lowercase.

Two different systems have been devised by two separate commissions to describe species and hybrids, but both are fundamentally related to the system devised by Carl Linnaeus. The International Code of Botanical Nomenclature (ICBN or the Botanical Code) describes how species found in nature are named with latin binomials, and is regulated by the International Botanical Congresses. The International Code of Nomenclature for Cultivated Plants (ICNCP or Cultivated Code) deals with those plants that have entered cultivation by man, including cultivars of species and natural hybrids, and grexes and cultivars of artificially-produced hybrids. The Botanical Code is primarily of interest to Taxonomic Botanists who attempt to apply the binomial system devised by Linnaeus in an unambiguous way; while The Cultivated Code is primarily of interest to those who cultivate, propagate or hybridize with plants that have entered cultivation. It is primarily the Cultivated Code that comes under scrutiny in this article.

How Does Orchid Nomenclature Work?

Similar to other plant families, the binomial system has been extended to facilitate naming valuable cultivars in the orchid family.

Whats in a name

In the example above, you can see the normal binomial form in the genus, (Phal., abbreviated from Phalaenopsis), and the grex (which would correspond to the specific epithet for a species). But there are two more terms as well. There is a cultivar epithet, that identifies a single cultivar, and all of its divisions or propagations, (including mericlones), and a term that represents an award that cultivar has won from the American Orchid Society. The cultivar epithet and the award are optional terms. Not every plant is worthy of being named, and it follows then that not every plant is of sufficient quality to receive an award.

In the example below, you can see the form as it applies to a species, instead of a hybrid. In this case, the species also has a forma epithet. Taxonomists can give a subspecies, a varietal or a forma epithet to a species in order to differentiate between the type species and a variety of the species that has horticulturally significant differences. In this case, equestris f. aurea has only carotenoid pigmentation and no anthocyanin pigmentation in the lip, causing it to be yellow, and has been given a forma epithet to keep it distinct from the typical pink or red lip of the type species. This example also shows a cultivar epithet and an award from the American Orchid Society. In this case, the last two terms are optional; while not all species have subspecies, varieties or forms, this one is a form, but not all plants of a given species are worthy of receiving a cultivar epithet, nor an award. Forma is often used to differentiate between color variants within a species; alba forms, for example. A subspecies is more distinct than a variety, a variety more distinct than a form.

Whats in a name

Sometimes you will see a person's name in parenthesis after a binomial. This is to indicate the taxonomist that described that species using that name. This is helpful for new descriptions, controversial descriptions, or for species that have changed names over time. It is a more specific way to name a species, and you will generally only find this in the context of a discussion between taxonomists or botanists or perhaps at an arboretum or botanical garden. Eric Christenson has recently recommended moving the species formerly in Doritis into Phalaenopsis, so you might choose to write Doritis pulcherrimma like this: Phalaenopsis pulcherrimma (Christenson).

This sytem has existed for decades, and the only real confusion that it has precipitated has been due to ignorance. Whether you choose to learn the nomenclature or not is up to you; indeed, you can remove the label from the plant and throw it away if that suits your fancy. The lack of a tag certainly does not interfere with the aesthetic value of the flowers in any way. But once the plants enter the trade without this information, something of value is lost. Nobody will have the opportunity to learn by the label where their plant originated from, what the constituent species are in the case of a hybrid, or important clues to the cultural requirements in the case of a species. People will have lost the opportunity to make their own choice about labels. Ignorance will have won out over established horticultural nomenclature; laziness over discipline; selfishness over regard for others.


Lack of care, not understanding nomenclature, language issues, or outright deception result in numerous problems related to mislabeling. Peter Lin suggested the example of Phal. Brother Dawn (Natasha X Misty Green), which has been awarded by the AOS under the cultivar epithets 'Cy' HCC/AOS, 'CY' AM/AOS and 'C.Y.' AM/AOS. These are probably the same cultivar, the award descriptions are almost identical. People often confuse varietal and cultivar epithets. People often fail to give a cultivar epithet to mericloned plants, leading to a great deal of confusion. There are plant labels printed in English by people for whom English is a second language, containing so many errors that it is virtually impossible to determine what they mean. There are nursery workers for whom English is a second language, so obviously incorrect labels are attached to plants; tags for pinks in the pots of whites, for example. There are people who put their own cultivar epithet on mericloned plants that either do or do not have a cultivar epithet on them already. There is one cultivar of one grex (Ever Spring Prince, if memory serves), that is in the trade, being sold under at least five different cultivar epithets.

These mislabeling problems precipitate all sorts of issues. One reader responded that he had what appeared to be a very nice mericlone Cattleya that was nominated for judging, but then failed to receive an award, because it was thought to be an improperly labeled mericlone, having no cultivar epithet. It must be very frustrating for Judges and for the owners of plants, where one mericloned cultivar is being shown under several different cultivar epithets.

Whether this mislabeling is due to language issues, lack of process, or outright misrepresentation, it causes a lot of problems for the committed grower or hybridizer, orchid judges, nurseries that want to sell properly labeled plants, and serious hobbyists. The author would like to see more care taken in the labeling of orchid plants.

What About Genus and Cultivar Epithets Alone?

In many other plant families, it is common to see plants labeled in the trade with the genus and cultivar epithet. This is a shame, as the species (or grex, in the case of a hybrid) tells you more about the plant than the genus or cultivar epithet. In the case of a species, the specific epithet allows you to know where the species occurs, so you know under what conditions it thrives. It allows you to know what time of year it flowers. In the case of a hybrid, the grex tells you what parent species are in the hybrid, so you know how it prefers to grow and when it is likely to flower. Some orchid genera have literally hundreds or sometimes over a thousand species, (Dendrobium and Bulbophyllum for example), found over huge geographic regions with disparate environmental conditions. It is therefore evident that the genus alone is quite insufficient to give adequate information as to the origin and culture of a given species or hybrid.

It is becoming increasingly common for orchids to be labeled in the genus and cultivar epithet manner. In fact, the International Code of Nomenclature for Cultivated Plants recently gave it's blessing to using this "system" of nomenclature for orchids. This is a shame. Not only do you lose information about what it is and where the original material came from, but in the case of orchid hybrids, you lose over one hundred years of painstaking record-keeping that has been done by the Royal Horticultural Society and by breeders, so you know precisely what a given orchid hybrid is composed of. Supposedly, you cannot use the Genus/Cultivar Epithet form where the same cultivar epithet is being used in the same genus. Unfortunately, there is no place these cultivar epithets are recorded, so it is not a reliable system. How many cultivars of red hybrids might be called 'Candy Apple' or 'Fire Engine' or something similar? You cannot show plants with unknown parentage for awards at most orchid shows, (including American Orchid Society awards), and you cannot register hybrids made from them either. If it is good enough to propagate, it is good enough to label properly. This author hates to think where this shortsighted "system" will lead in a few decades.

Numerous orchid plants are entering the trade now with only the genus, or with just the genus and cultivar epithets. Among orchids, this has not been done before. Now with the quantity of Phalaenopsis pot-plants being sold this way, it is becoming a real problem for the people who care about what their plants are. The author refuses to buy plants labeled this way, no matter how nice they may appear. The author encourages you to do the same. Tell the good folks at your local nursery, garden center or florist why you will not buy these plants: that to do so is to support the demise of over a hundred years of painstaking effort to properly label plants and record the parents of orchid hybrids.

As you can probably guess from this author's comments above, he does not believe that it is a good idea to adopt this "system" for orchid nomenclature. If that is the conclusion that you have reached, you are correct. The author would be very interested in precisely how the good people at the International Code of Nomenclature for Cultivated Plants plan to make sure that duplications within a genus do not occur, and just how people are supposed to determine what the parents are of a hybrid so labeled. The author would also be very interested in having the American Orchid Society explain why they do not feel this policy is at odds with their stated objectives to "Provide Global Leadership" in orchids, and to further education related to orchids.

It is the author's opinion that the only ones to benefit from this new policy are those that feel a proprietary interest over the results of their hybridizing efforts, and do not wish to share information with the rest of the orchid world. The author would ask these hybridizers just where they would be if breeders for the previous one hundred years took the same proprietary approach. This is simply unmitigated selfish, uncivilized behavior, and should neither be condoned nor supported.

For More Information

"Botanical Latin" Covering the History, Grammar, Syntax, Terminology and Vocabulary of Botanical Latin. By William T. Stearn, published by David & Charles, Third Edition, © 1983. Linnaeus really owes a debt to earlier scholars such as Pliny the Elder, for laying a foundation of using Latin to describe plants so that botanical scholars living in geographically isolated areas could benefit from each other's work. If you are interested in Botanical Latin, this book is an exhaustive reference. Available through the bookstore on this site.

"Gardener's Latin" By Bill Neal, published by Algonquin Books, © 1992. A delightful little book, highly readable, which contains a brief history and overview of botanical latin, and definitions of many latin epithets that you will find throughout horticulture. It also has some very interesting anecdotes in the margins. Available through the bookstore on this site.

"The Handbook on Orchid Nomenclature and Registration" is perhaps the definitive source for information on this subject. You should be able to obtain it from the American Orchid Society Bookstore. My copy is the Third Edition, published in 1985. It was prepared by The Handbook Committee of the International Orchid Commission, with cooperation and services of The Royal Horticultural Society. Published by and at the authorization of the International Orchid Commission through the financial support of the American Orchid Society Inc., and the Royal Horticural Society as the International Registration Authority for Orchid Hybrids.

I wish to thank the following people who after reviewing this article, made suggestions that resulted in corrections, refinements, clarification or additional information: Stan Dinsmore, Keith Joiner, Robert Dale Kloppenburg, Alan Koch, and Peter Lin.

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Robert Bedard Horticulture • Scotts Valley, CA • (831) 439-9484
Content ©2004 by Robert Bedard. Last update: 06/20/04
Dtps. Asahi Image Copyright Evelyn Jenkins Drew