An introduction to botanical nomenclature, the binomial system and plant classification.
I am going to explain what botanical nomenclature is and what the binomial system of naming plants is. I’ll also tell you why we still use Latin.
Plant names and learning the Latin can seem daunting, but once you break it down it becomes, relatively, straight forward. You will quickly start to understand why we classify plants in the way that we do, and why we use Latin names as the botanical standard.
These are the questions I first asked about this subject:
What is “botanical nomenclature”?
Quite simply, it is the formal, scientific way of naming plants.
Is plant nomenclature the same as “taxonomy”?
No - it is related to it, but is slightly different. The taxonomy side of things is to do with the classifying (grouping) of plants. It is then botanical nomenclature that gives the names to the plants, as a result of this classification.
What is the bi-nominal system of naming plants?
It is a two-part way of giving plants their name. Every plant name consists of two parts - the Genus and the species. The genus is the group that the particular plant belongs to (e.g. Crassula) and should be written in italics, with a capital letter at the beginning. The species (also know as a “specific epithet”) describes the plants within the genus (e.g. ovata). It should also be written in italics, but without any capitals.
Sometimes a third part is added to a plant name, if there is a variation in a plant species - a naturally occurring variety or a form developed in cultivation known as a ‘Cultivar’.
How can I remember how to write plant names and what each bit means?
It helps to remember this:
- Genus refers to the “generic” name.
- Species refers to the “specific” name. It’s nearly always an adjective which describes its characteristics.
- Variety refers to a “natural variation”.
- Cultivar refers to a form “developed in cultivation”
Why should we use Latin and why don’t we use common names?
Latin is a universal, “dead language”. This means it is politically neutral (hoorah), is known in every country and is no longer spoken in day-to-day conversation.
Common names can be confusing. Lots of plants have many common names - for example, the common wild pansy is known by lots and lots of names including; Biddy’s Eyes, Monkey Face, Heart Pansy, Tittle-My-Fancy and the rather mouthy Meet Her In The Entry Kiss Her In The Buttery!
By using Latin, it prevents confusion, which is especially important when ordering plant-based food or medicine products.
Some of my plants have rather misleading common plant names -
- Money Plant - there are so many plants that are referred to as the money plant or tree. Two of my favourites are the Crassula ovata (also known as the Jade Plant) and Pilea peperomioides...despite having multiples of both, I am still yet to receive my millions!
- Ponytail Palm - the Beaucarnea recurvata is not actually a palm at all (it’s a caudiciform).
- Devil’s Ivy - the Epipremnum aureum is not an ivy. It’s definitely not a devil either, but it may be called this because it’s quite hard to kill (even though in my book, that makes it an angel).
What are specific epithets?A “specific epithet” is another word for the plant “species”. It is usually an adjective and will often tell you something about the plant. E.g. ovata means “egg-shaped” and refers to the leaf shape of the Crassula ovata (the jade plant).
The species or specific epithet often describes the way the plant looks, its colour, its place of origin, its lifespan or its habit. Once you know this, it can be quite fun to learn the Latin.
Here are some examples -
Specific epithets that describe the way the plant looks:
- rotundifolius means “with round leaves”
- maculosus or maculatus means “spotted”
- colosseus means “gigantic”
Specific epithets that tell you the colour (usually of the flowers):
- lutea = yellow
- rubra = red
- nigra = black
- alba = white
- rosea = pink
- purpureus = purple
Specific epithets that tell you where the plant is from:
- japonica from Japan
- gallicus from France
- germanicus from Germany
- orientalis from the east/eastern
- occidentalis from the west/wester
Specific epithets that tell you the plant’s lifecycle:
- annuus is an annual plant
- biennis is a biennial plant
- perennis is a perennial plant
Specific epithets that tell you the plants growth habit:
- pendula is a plant that is weeping in habit
- deflexus is a plant that is bent sharply in a downward direction
- melancholicus is a plant that is drooping in habit
There are literally hundreds, if not thousands of species and specific epithets. Next time you look up a plant or read a label in a garden centre, consider the second part of the plant’s name, and see if it tells you anything about the particular plant. If you took Latin at school, you’ll be ahead of me.
What is the difference between a variety and a cultivar?
Varieties tend to be naturally occurring variances in a plant genus. These are nearly always written in Latin, whereas cultivars are usually written in modern language (there are some exceptions).
When a cultivar is present at the end of a plant name, it tells you that a different form of the plant species was developed in cultivation (a man-made variance). These plants are sometimes given the name of the person that cultivated it, or given a name to commemorate an event.
I hope that I have helped you to understand that the names given to our plants actually means something. I find it incredibly interesting. Once you get into it, it will become something you'll find yourself researching more and more.