You spot a tall, beautiful, flowering plant and want to grow it in your own space, but depending on where you are in the country you could be told this plant is called fairy cap, fairy bells, fairy fingers, fairy gloves, fairy’s petticoat, ladies’ thimble, goblin’s gloves, cow flap, monikers, dog’s lug, dead man’s bells, witches’ fingers, or lustmore, and they will all be names for the common foxglove. The Gaelic for foxglove is ‘lus nam ban-sìth’, meaning plant of the fairies. 

Digitalis purpurea to call it by its proper name, is know in different parts of the country by different names, and while this is fine locally, it does not help if you are trying to find or order the same plant, in a different area.

The Latin name ‘Digitalis’ means ‘finger-like’, and the shape of the blooms is certainly what has given rise to such a wide variety of common names for Digitalis purpurea. 

Without a mutually agreed name, confusion is inevitable, and plants have been classified and named for one very good reason: so we can clearly distinguish one from another. With an estimated number of plants in excess of 270,000 on the planet, a system of nomenclature had to be devised.

Binomial Nomenclature

Plants have been classified botanically using the same language worldwide, Latin. To accurately distinguish between them, each is assigned a unique name – often referred to as the Latin name, the scientific name, or the botanical name.

The naming system we use for plants is called binomial nomenclature. While each plant may have multiple common names, it should only have one binomial name.

Known as the International Code of Botanical Nomenclature, the code is based on a two-name (binomial) system developed by Carl Linnaeus, an 18th century Swedish naturalist. He classified plants by giving them a first name, being the genus, and a second name, the specific epithet. Put together they provide a name that can only name one plant (species), like Helleborus niger or Alchemilla mollis. This name is universal, and part of an international system used by scientists and professionals.

It means that wherever you are in the world, and whatever language you speak, you will be able to identify a plant, and communicate with other growers. A Rosa rugosa (Japanese rose) will be recognised as such whether you live in Aberdeen, Adelaide, or Athens.

The common name of a plant is simply the name that caught on in a certain area over time. Plants can either have a common name and a botanical name, multiple common names and a botanical name, or a botanical name but no common name. Sometimes, different plants share the same common name, but the botanical name is unique to only one species.

How to Read Plant Names Correctly 

The plant genus is listed first and is always capitalized. The species (or specific epithet) follows the genus name in lowercase, and the entire Latin plant name is italicized.

Genus

The genus represents a group of plants with similar characteristics – all the plants in the genus will share a recent common ancestor and look similar to each other. They are all likely to need similar growing conditions and will have similar pest and disease tolerance.

Species

The species starts with a lowercase letter. All plants in the same species can reproduce with each other.

Variety

A variety is a plant that has a naturally occurring variation from the main species, that is noted using ‘var.’ This comes about when two plants have cross-fertilised in the wild. For example, Geranium sanguineum var. striatum is a striped variety of a hardy cranesbill geranium.

Subspecies

Sometimes within a species, small groups of plants can be found that are subtly different from the norm, having evolved in a distinct geographical area. This difference is noted using subsp. after the main plant name. 

Anthemis punctata subsp. cupaniana, commonly known as a Sicilian chamomile, is a subspecies of Anthemis punctata, and Euphorbia characias subsp. wulfenii, commonly known as Mediterranean spurge, is a subspecies of Euphorbia characias.

Cultivar

A cultivar is any new plant that comes about in cultivation (rather than in the wild), by crossing two related plants. This could be a result of deliberate breeding, or it may be a lucky accident in the garden or nursery. Cultivar names are listed with each first letter capitalised, in quotation marks. This is often the name of the person who bred or discovered the plant, or the colour of the plant. 

Whereas the genus, species, variety, and subspecies names are Latin, cultivar names are usually not. Clematis armandii ‘Apple Blossom’ as an example, tells us that the flowers are pink-tinged.

Sometimes the parents’ names are not known, or have been lost, so only the genus and cultivar names are used. For example, Dahlia ‘Doris Day’.

Dealing With No-name Plants

If you have plants without a name and you identify them through pictures or social media, never assign a cultivar name to them. Use only the botanical name to avoid future confusion. For example, Phlox paniculata ‘David’ is a common white phlox. Many gardeners who have an un-named white summer phlox call it ‘David’, but there are numerous other such white phlox, and none of these should be called ‘David’ because they are genetically different.

How Does the Name Help?

Botanical plant names can look complicated, but they are actually quite simple once you get the hang of them. More importantly, there is a very good gardening reason for botanical names: they can tell you a lot about a plant, including its main characteristics, where it originates, and how to care for it correctly.

Here are some commonly used Latin words in plant identification:

Habitat

alpina/alpinus – alpine
campestris – field
maritima – coastal
montana – mountain
pratensis – meadow
sylvatica – forest 

Colour

alba/albus – white
caerulea/caeruleus – blue
coccinea/coccineus – scarlet
argentea – silver

Area of Origin

chinensis – China
japonica – Japan
sibiricus – Siberia
occidentalis – America
orientalis – Asia 

Habit

columnaris – columnar
dentata – toothed
fruticosa – bushy
gracilis – slender
reptans – creeping
scandens – climbing

Characteristics

angustifolia – narrow leaves
fragans/fragrantissima – scented
foetida/foetidus – smelly (unpleasant)
grandiflora – large-flowered
odorata – perfumed
officinalis – has herbal uses
sativum – grown for food

While this classification system many appear confusing at first, having a commonly agreed, scientific system of identification is essential for accurate recognition of plants across the world. 

Plant Families

Every genus belongs to a bigger group of plants, called a family. While they may look very different, they share common characteristics. Aquilegias, buttercups, clematis, marsh marigolds, and aconites for example, all belong to the family Ranunculaceae which numbers over 1800 species. Michaelmas daisies, globe artichokes, and sunflowers are members of the Asteraceae family; roses, strawberries, apples, and hawthorn are members of the Rosaceae family, and tomatoes, potatoes, chillies, and deadly nightshade all belong to the Solanaceae family. The family is not included in the plant name, but it is useful to be aware of it.