Master Gardener: Why plant names matter
Occasionally, I am asked why I use botanical names for plants and shrubs, rather than simply calling them by their common name. To answer the question, let me ask you a question….
Have you ever fallen in love with a plant at first sight? The first thing you want to know is the plant name. All too often, you will get a “common” name that is not really helpful. The friend whose garden you saw it in may know it only as her Aunt Mary’s zinnia. Common plant names are like nicknames. While almost everyone you know may call you by a nickname, it may be that your parents have one nickname for you, your friends another, and your partner a third.
What you really need to know is the plant’s botanical name. Just as you’re expected to provide the first and last name on your birth certificate or driver’s license, plants have two-part names. We typically alphabetize a list of names with the last name first, plant names have the more general name — the genus — first, followed by the more specific name — the species — second. Typically, botanical names are italicized and only the genus is capitalized. Think of plant names like family names – your family name followed by your given name, like this: Jelinek, Roxann. ‘Jelinek’ is the genus and ‘Roxann’ is the species.
A quick definition of plant prefixes and suffixes:
A genus refers to a group of plants which share certain structural characteristics. The genus name may come from mythology, literature, people, places, or something the plant resembles.
The species name usually refers to a place where the plant is native, the plant’s appearance, or the name of the person credited with discovering it. Individual species are precisely identified by analyzing the flowers and seeds of each plant. The determining criteria might be the number of petals on the flower, or a certain characteristic of the seed.
Varieties are subdivisions of species. They refer to naturally occurring changes or mutations which create a distinctively different plant in appearance. This often refers to flower color, or variations in growing habits.
Cultivars refer to varieties which, although they occurred naturally, can only be replicated by asexual propagation and human intervention by cloning.
Hybrid refers to new varieties of plants, which were created by humans through cross pollination of separate varieties. The naming of hybrids is usually done by the creator of the hybrid, and is proceeded by an ‘x’.
For a quick example to illustrate how different terms are used in the naming process, I will use Blue bells of Scotland, Campanula rotundifolia.
campan- means ‘bell’ and refers to the bell shaped flowers.
rotund- means round, foli means leaves. (rotundifolia = round-leaved)
When a new variety was discovered which had white flowers, rather than blue, it was given the designation ‘alba’ (meaning white) added at the end of the name.
Campanula rotundifolia ‘alba’ would therefore describe a plant with white, bell shape flowers, and round leaves. (There, that was not so hard, was it?)
Some plants are known by their botanical names rather than common names, but we tend to know only their genus: Begonia, Hosta, Iris, and Zinnia, for example! To identify any particular plant we need to know the species and often the variety or cultivar. And that’s precisely why names matter. Knowing a plant is an Iris won’t help you find out much about where and how it grows unless you know the species. And if you want a plant that has that particular flower shape and color, you’ll need to know the variety or cultivar name. Also different species may not look that different, but they may require very different growing conditions, or may be a hardier perennial etc.
The botanical name is unique to a specific plant. No other plant in the world will have the same botanical name. Common names for a plant, by contrast, will be different in different languages, may differ by region within a country or may be applied to several different plants. For instance, the morning glory is also known as bindweed, small bindweed and liseron des champs. But if you want to grow this flowering plant in your garden, ask for “Convolvulus arvensis,” and you will receive the right plant.
The botanical name of a plant is the key to finding everything known about that plant and its cultivation. If a gardener wants information about a particular plant from books or online sources, searching by the botanical name ensures the retrieved information will be about the correct plant. Botanical names are universal; the same botanical name applies to a plant wherever in the world it is found, grown or studied.
Resource: Debbie Green, Extension Master Gardener; University of Minnesota Extension