(To go in annuals and perennials section)
Why use Latin or scientific names for plants?
Many gardeners try to avoid the use of Latin or scientific names for plants as they find them long and difficult to pronounce. However, once the concept is understood, Latin names can actually be quite helpful for identifying plants. Scientific names for plants were originally developed because different common names are used for plants, depending on the region or language. For example, the invasive grass weed Elytrigia repens has the common names couch or twitch. Latin was the original language used in scientific literature and so it was decided to keep using it for scientific names. In addition, the Latin language is no longer spoken as a native language and is therefore unchanging, so Latin words do not take on new meanings or connotations.
To fully understand scientific names, we must briefly look at taxonomy, which is the study of classifying and naming organisms. Each living organism is classified into a series of groups or taxa, which start with the five kingdoms and follow down through the phylum, class, order, family, genus and species. Carolus (Carl) Linnaeus (1707-1778) was a Swedish naturalist, who is credited with developing modern taxonomy. He designed the binomial (a Latin word meaning two names) system, whereby each species was identified by two words, the first being the genus name and the second a specific epithet, e.g. Lobelia erinus. The plant used in this example is a small annual with bronze leaves and deep blue flowers that are produced continuously from spring to autumn. However, the genus Lobelia includes other garden plants, such as Lobelia laxiflora, a perennial plant suited to tropical conditions with dark green leaves and red and yellow flowers that appear in summer.
The scientific name is always written in italics and the genus name is always capitalised (the specific epithet is in lowercase). Sometimes only the genus name is given. There are several reasons for this, such as the plant has been identified to the genus but not species level, e.g. Hosta sp., or the reference is to all the species in a particular genus, e.g. Rosa spp. (sp. and spp. are the singular and plural abbreviations for species). In addition, many garden plants have arisen from crosses of parent plants that are different species within the same genus. For example, many camellias are hybrids between Camellia japonica and C. saluenensis, and these are given a collective name preceded by a multiplication sign, e.g. Camellia x williamsii. Note that sometimes the genus name is abbreviated to the initial capital and a full stop, followed by the specific epithet, e.g. Camellia saluenensis was abbreviated to C. saluenensis in the previous sentence. This is only done when there is no chance of misinterpreting the abbreviation for another genus name.
A plant may be given a Latinised name after the person who first discovered it or someone who is prominent at the time. For example, the genus Fuchsia is named after the German physician and herbalist Leonhart Fuchs. Names can also be descriptive, particularly the specific epithet. For example, ruber (rubrum), sanguineus, roseus and coccineus refer to plants with red or pink colouration (e.g. Schizostylis coccinea has bright red flowers in autumn), lutea is for yellow colours and albus (alba) is white. Other names refer to fragrance (odorata or ororatum), flower shape or size (flora is Latin for flower so grandiflorium means big flower), leaf shape (folium or folia means leaf, so trifolium refers to three-leaved) and place of origin (novaeselandiae is from New Zealand and sinensis means Chinese, while borealis, australis, occidentalis and orientalis refer to northern, southern, western and eastern, respectively).
So when you next see a scientific name in a book or on a plant label, don’t dismiss it. Take a good look and see if you can work out something about the plant from the name. Also remember that much of the English language is derived from Latin so the pronunciation is very similar. Just break the word down into syllables as you would with a long English word.