Why do plantspeople like using the botanical plant names so much? I promise you that they are not being pretentious. This seemed the most logical explanation to me, as a teenager, whilst on family walks with the (now) Ecologist Big Sister, during the first term of her Masters degree in environmental science. I thought she was just showing off with her Urtica dioica and Cirsium vulgare. What’s wrong with just calling them stinging nettles and thistles?
The binomial system we use for naming plants was first applied consistently by the Swedish botanist Carl Linnaeus in the mid-18th century. Usually, a binomial plant name consists of a family name, known as the genus (capitalised), followed by its species (all lower case), and is printed in italics.
The words used to name plants tend to derive from a mixture of Latin, Greek, native names or places of origin. Here are five reasons why it is useful to know and apply the full binomial botanical names for plants.
Unique identifier
The botanical name given to a plant species is unique, and therefore the key to its identification. For example, there are two different plants both known by the common name of bluebell; Hyacinthoides non-scripta (English bluebell) and Campanula rotundifolia (known as bluebell in Scotland and harebell in England). Using the unique botanical name provides complete clarity on which specific plant we are talking about.
Campanula rotundifolia - locally known as bluebell in Scotland and harebell in England
Hyacinthoides non-scripta - known as bluebell in England
Internationally understood
Botanists across the whole world use the same botanical names for plants, irrespective of their own native tongue. Common names can vary within countries as well as between countries. For example, marsh marigolds may also be known to us in the UK as kingcups, Maybobs or any other of the ninety or so common names. In Germany they have around 140 different common names, and a further sixty in France. However, botanists attending an international conference will refer to this plant as Caltha palustris and can all be certain over which plant is being discussed.
Caltha palustris
Stability
Recent advances in genetic analysis and DNA sequencing have resulted in, every now and again, a plant being reallocated to a different genus. But on the whole, botanical plant names tend to be stable and unchanging over time, unlike common names and even language in general. So hopefully, the botanical plant names I learned (and am still learning) whilst studying for my RHS exams will still be the same when I am gardening in thirty (and hopefully more) years’ time.
Appearance and characteristics
This is where a little knowledge of Latin or Greek comes in handy. The botanical plant names can sometimes give us a clue on the appearance of a plant; the shape or texture of the leaves, its habit or general size, colour, or even its nutritional or medicinal properties. Here are three examples
Hydrangea quercifolia – Oak-leaved hydrangea, Quercus being the genus for oak species;
Fraxinus excelsior – Common ash, excelsior meaning ever taller, or upwards;
Saxifraga bronchialis – Yellowdot Saxifrage, traditionally used to treat bronchitis.
Native habitat
The botanical name can also give you a clue as to its native habitat, and hence the conditions it would prefer to be grown in!
canadensis – originally native to Canada e.g. Amelanchier canadensis (serviceberry);
japonica – originally native to Japan e.g. Chaenomeles japonica (flowering quince);
damascenus – associated with Damascus, Syria e.g. Nigella damascena (love-in-a-mist);
sibiricus - associated with Siberia e.g. Iris sibirica
Further reading
A basic grasp on the above five points will earn you an easy five marks in your first RHS Level 2 paper. If you are interested in finding out more about plant names and enjoy illustrated texts, have a look at the RHS’ ‘Practical Latin for Gardeners’ by James Armitage (2016).