The Classification System

by Steve Stroupe

How do plants get named? What’s the difference between scientific
and common names? Is there a baby plant name book where proud
parents choose names for their new green babies?

Plants are named for the same reason people are named; they have feelings and don’t want to be referred to merely as “hey you,” so sensitive botanists thoughtfully gave each plant their own special name – usually in Latin and/or Greek, and another one in plain English.

The Classification System

Along with common names, plants are also classified with indecipherable (to the layperson anyway), but scientifically precise Latin and/or Greek names … (yawn). Why Latin? Because after the Dark Ages it was cool to be smart again and all the really bright people spoke Latin, so … when plants started being named by botanists in the 16th and 17th centuries, Latin was naturally used.

For instance, the familiar Variegated Sweetflag is written as Variegated Sweetflag (Acorus calamus ‘Variegatus’). This two-name (binomial) system, which uses genus and species, is altered somewhat when a cultivar (man-made or discovered natural hybrid) is added to the mix. The cultivar name is flanked by single quotation marks and follows the genus or species name. Often the scientific names are italicized and/or enclosed in parentheses. Let’s look at where the name for this plant may have originated.

The Common Name

“Sweet” refers to the sweet, camphor-like fragrance released when the leaves are bruised or crushed. “Flag” comes from the Middle English word “flagge” meaning reed, so the common name means simply, “sweet reed,” and our particular plant is vertically striped with green and yellow, so we have a variegated sweet reed.

Unfortunately common names vary from region to region and country to country, so to insure that everyone in the world stays on the same page regardless of native language, scientific or Latin names are also employed. Here is where the binomial naming system comes in.

Let’s Talk Latin and Greek

The Genus name, Acorus, is derived from the Greek word “acoron,” a name used by Dioscorides, which in turn was derived from “coreon,” meaning “pupil,” because it was used in herbal medicine as a treatment for inflammation of the eye. I was unable to determine why this name was specifically applied to Sweet Flag, but it may have had something to do with the fact that these plants used to be lumped in with the aroids [Araceae]…Taro, Golden Club, Arrow Arum, Jack-in-the-Pulpit etc…and may have enjoyed a more discernable connection as a result of its erstwhile classification.

The Species name, Calamus is associated with love, sex, and Greek tragedy, and why not? Kalamos, the son of the river god Maeander from which our word meander is derived (as in meandering stream), was beside himself with grief when his lover drowned in the river, so he was transformed into a reed. When these reeds rustle in the wind it is seen as the lamentations or sighs of Kalamos. Walt Whitman’s poem ‘Calamus’ in ‘Leaves of Grass’ is thought to have been inspired by this story.

The word Kalamos is believed to have a common origin in Latin, Greek, and Sanskrit, which leads scholars to conclude that this word is older than all three languages, possibly Proto-Indo European, which is believed to be the parent language of all three.

What about the Cultivars?

Cultivar names applied to man-made hybrids are usually not that interesting, origin-wise, and can often cause quite a bit of confusion, especially in the water gardening industry. Cultivar names are based solely on the whim of the hybridizer, and can be named after wives, children, in-laws, mistresses, stars, planets, food, gods, places, pets, mythological heroes or famous people … virtually anything at all. Cultivar names must be registered if an official note and record is required by the hybridizer. In the case of our example, ‘Variegatus’ is simply the Latinized form of variegated which refers to different colored zones in the leaf or stem of a plant.

The official registering agency for water lilies is the International Waterlily and Water Gardening Society (IWGS) which was appointed for this task by International Society for Horticultural Science. To correct the confusion in the world of water lilies, the IWGS has traveled backwards in time to insure that the varieties which bear their current name are indeed correctly labeled. No mean feat since a lot of popular cultivars date back to the 19th century.

Kirk Strawn, (now deceased), one of the deans of American water lily hybridizers, playfully articulated this problem by listing Nymphaea ‘Attraction’ in his catalog…in eight different versions in descending order of perceived authenticity, and with corresponding reductions in price. To my knowledge, this is the best satirical articulation of this problem which has ever been offered publicly.

Truth in Naming

A few years ago, it was discovered that one of the most popular hardy water lilies, a beautiful coral pink cultivar named Nymphaea ‘Fabiola’ wasn’t really ‘Fabiola’ at all, but a brazen imposter. The real ‘Fabiola’ was a much less impressive plant, but was indisputably the rightful owner of that name. The name was returned to its rightful owner amid much furor and fretting, and a new name was given to the old ‘Fabiola’, now christened Nymphaea ‘Pink Beauty’.

Old habits (and names) die extremely hard. Sales of ‘Pink Beauty’ never reached that of the old ‘Fabiola,’ which is very lackluster by comparison, and the rightful, resurrected ‘Fabiola’ still lives in dark obscurity despite the nomenclatural correction. A Pyrrhic victory to be sure.

In real estate law, there’s a legal principle known as “adverse possession”: “Adverse possession is a principle of real estate law whereby somebody who possesses the land of another for an extended period of time may be able to claim legal title to that land.” ‘Fabiola’ the imposter had been “possessing” its name “adversely” for a lengthy period of time, and had become extremely well known and revered under this name. Had not waterlily people been so prickly and exacting about correct nomenclature, ‘Fabiola’ could have still kept its purloined name under “adverse possession” and retained its eminence as one of the nicer pink hardy varieties instead of disappearing off the radar for most hobbyists as a result of the corrected name change.

Another problem which plagues our pond community is the indifference or callous disregard for insuring that varieties currently being sold are labeled correctly by growers and retailers. This is just plain sloppiness and laziness, and represents a very different problem than the one described above and one which is being addressed by Water Gardeners International (WGI), a non-profit organization based in Cocoa Beach, Florida with their Truly Named© Program.

Getting What You Pay For

Truly Named was set up to ensure that water lilies are correctly labeled and are indeed the cultivar the plant tag says that it is. Waterlily growers, wholesalers, and retailers who are members of WGI have voluntarily committed to providing the home water gardener with plants which, to the best of their knowledge, are true to their labeled name. According to the WGI website, “Many people who purchase waterlilies initially want something pretty and colorful for their ponds. However, as interest and understanding increase, they often desire certain waterlilies, those with recognized names that assure specific characteristics. Truly Named WGI © members believe water gardeners deserve to receive what they pay for and therefore have joined this program to give their assurance that, to the best of their knowledge, they are providing correctly named plants.”

This voluntary program is growing at a steady pace with members from all over the world participating. The WGI website explains, “Consumers who buy from participants in this program have the assurance that everything possible has been done to insure that varieties being sold are true to name. It must also be noted that there are other reliable waterlily growers and retailers who do this voluntarily, but may not be a member of this program.”

Always an Interesting Story

It’s a fun exercise to just pick some plants at random and see what a wealth of information can be gleaned from their nomenclatural history. One never knows what’s in a name. There’s always an interesting story behind every plant, no matter how ordinary it might appear. And most people think Latin is boring!

For more information on waterlilies, nomenclature, and the Truly Named© program, visit the following websites:

International Waterlily and Water Gardening Society – www.

Water Gardeners International –

Plant Delights Nursery –

A Note on the Code of Naming

The rules governing the naming and classification of plants and fungi are contained in the International Code of Botanical Nomenclature, maintained by the International Association for Plant Taxonomy. The process of naming plants is taken very seriously by the scientific community, and by those who make pretensions to being seen as scientific.

Fortunately for us all, not all plant folks are wound so tightly about plant names. Tony Avent, a world-renowned horticulturist and owner of Plant Delights Nursery in Raleigh, North Carolina which specializes in unusual perennials, has the following delightfully irreverent little blurb about botanical taxonomy in his current nursery catalog.

“We use all means at our disposal to make sure the plants are named using
correct horticultural nomenclature. Our primary references include the
RHS Index of Garden Plants, Hortus III, Jelitto’s Perennials I & II, et al…
If no information exists on a plant, which often happens, we throw a cookout for the neighbors, who after a few drinks begin throwing darts at Jelitto’s Perennials I & II, along with the remainder of Hortus III.  When botanists differ on correct nomenclature, we hop in the pickup, find a few taxonomists, and throw darts at them.”

* Steve Stroupe is an aquatic plant nursery owner, and co-author of three books on the care and cultivation of aquatic plants. He lives in rural Alabama along with hundreds of beautiful aquatic plants.