All known plants have both common and botanical names. And very often a plant has a lot of common names.
This can be very confusing, misleading and even critical.
Confusing and misleading because a common name often refers to the plantgenus - and not to the different species in that genus.
And critical, because a plant genus often comprises both edible and poisonous species.
So, it's not only practical, but also reassuring that every known plant has only one botanical name, though equivalents may occur.
Botanical names are used throughout the world.
So, knowing the botanical name of a plant, it's easy to look it up in a plant encyclopedia, local field guide or other botanical books. Even books in foreign languages.
Botanical names are written in Latin. Each botanical name is composed of two Latin names. Both names are always written in italics.
The first name indicates the genus of the plant. The genus name always starts with a capital letter.
The second name indicates the species. The species name always starts with a small letter.
The botanical name for Common Thyme - also known as Garden Thyme - is:Thymus vulgaris.
Thymus is the name of the genus.
vulgaris is the name of the species.
This precise naming means that throughout the world Thymus vulgaris means the same thing.
Sometimes you will also see the following abbreviations added to the botanical names:
sp. = any species.
ssp. or subsp. = subspecies (inserted before the subspecies).
var. = variety of the species (inserted before the variety).
An x between the genus name and the species name indicates that the plant is a hybrid - a crossing between two species.
These abbreviations are written in non-italics.
It's The International Association for Plant Taxonomy, which has prescribed these rules for formatting botanical names.