“Why do we have to use long botanical names that are so difficult to pronounce, instead of sticking to the common type? And why do they keep changing the names of plants we’ve known for years?”
The questions were posed recently, and not for the first time, during our Weekending Show on Lionheart Radio.
Friend Carl, with whom I co-present the programme, also wanted to know because it irks him that a plant he’s just learned to address correctly is suddenly renamed.
The problem is that common names for specific plants vary between regions, let alone countries, so talking about your ‘spider plant’, ‘mother-of-thousands’ or ‘pennies from heaven’ might be okay locally, but will cause confusion elsewhere.
Furthermore, totally different plants often share the same common name, and many have none at all.
A favourite example relates to a common perennial weed that takes root in lawns and borders alike. In the home counties it’s variously known as swine’s snout, dog’s posy, peasant’s clock and pittley beds. No doubt it has different names in Scotland, Ireland and Wales, but you’ve had enough clues to recognise it as dandelion, which is also a common name.
Here’s the crunch. If you walked into any garden centre from Athens to Zanzibar and asked for an herbicide to treat dandelions, they’d be puzzled. A better chance of success would come with the internationally-recognised botanical name, Taraxacum officinale.
Plants are registered worldwide under a nomenclature scheme using internationally-recognised Latin. Originally devised by Carl von Linne (Linnaeus), in his Systema Naturae (1735), it introduced a sense of structure that persists today.
Name changes occur as botanists look beyond the external features of plant groups.
Plants are grouped in families if they share a set of underlying features, for example the family rosaceae embraces roses, cherries, plums and others. These are sub-divided into genera when several plants within a family share a wide range of similar characteristics, such as roses.
A further division (species) is made for a group of plants capable of breeding together to produce offspring. Subspecies are naturally occurring variants of a species, and varieties are a smaller subdivision of a species with a slightly different botanical structure.
Cultivars are distinct variants of species, subspecies, varieties or hybrids that have been selected or artificially raised. They are instantly recognised in catalogues by a capital letter and single speech marks.
So, the gorgeous, slow-growing conifer Chamaecyparis pisifera, Filifera Aurea, in this garden is a member of the family cupressaceae, which contains many attractive evergreen conifers. The genus name is chamaecyparis and the species is pisifera, which means bearing peas.
Filifera Aurea denotes that it’s a cultivar whose name interprets as bearing golden threads. This beautifully describes the dangling, thread-like foliage.