Understanding Garden Jargon
The terminology associated with plants and gardening can seem intimidating if you are new to gardening. However, the Latin name system is used all over the world, and a little knowledge of it goes a long way.
Although many plants have familiar common names such as “rose” or “lavender,” not every plant has one. As an added complication, several may share their name with other plants or be named differently in different regions and countries. Botanical names are used universally to avoid this kind of confusion, which makes it useful to know something about them. Botanical names classify each plant with two Latin words. The first word describes the genus (for example, Ilex) and the second, the epithet (for example, aquifolium). Together, they make up the name for a particular plant species, such as Ilex aquifolium (English holly). Other species in the same genus are given different epithets, such as Ilex crenata and Ilex serrata. The system has been developed so that the entire plant kingdom is divided into a universally recognized “family tree”.
A family may contain only one genus (for example, Eucryphia is the only genus in the family Eucryphiaceae) or many––the daisy family Compositae has over 1,000 genera. Each genus comprises related plants, such as oaks (genus Quercus) or lilies (genus Lilium), with several features in common, and a genus may contain one or many species. For example, a member of the genus Lilium could be any lily, but Lilium candidum denotes just one type. A species is a group of plants that consistently and naturally reproduce between themselves, generating plant populations that share similar characteristics.
Behind the Name
The two-part Latin name given to each plant can give useful clues to the plant’s geographic origins and natural habitat, as well as allowing similar plants to be grouped together.
The second part of the plant’s name denotes the species and often reflects the physical characteristic of the plant. For example, cyanus describes a blue plant, such as Centaurea cyanus, and Octopetala (as in Dryas octopetala) means “eight petals.” The species name can also reflect the person who discovered the plant (as in Magnolia wilsonii); its natural habitat (pratensis denotes a meadow-growing plant); or the plant’s country of origin (species called sinensis are from China).
Guide to Plant Classification
In horticulture plants are classified according to a hierarchical system and named primarily on the basis of the binomial approach (genus followed by species epithet). As an example, part of the family Rosaceae has been set out below, showing all levels of this system.
- Family: A group of several genera that share a set of underlying natural characteristics. Family names usually end in -aceae. Family limits are often controversial.
- Genus (plural: genera): A group of one or more plants that share a range of distinctive characteristics. Several (rarely one) genera are classified into one family. Each genus contains one or more species, and its name is printed in italic type with an initial capital letter.
- Species: A group of plants that breeds naturally to produce offspring with similar characteristics; these distinguish it from other populations in nature. Each species has a two-part name, conventionally printed in italic type.
- Subspecies: A naturally occurring, distinct variant of a species, differing in one or more characteristic. Subspecies are indicated by ‘subsp.’ in Roman type and an epithet in italic type.
- Varietas and forma: A varietas (var.) is a minor species subdivision, differing slightly in botanical structure. A forma (f.) is a minor variant of a species, often differing in flower color or look from others in the species.
- Cultivar: Selected or artificially raised, distinct variant of a species, subspecies, varietas, forma, or hybrid. Cultivars are indicated by a vernacular name printed in Roman type within single quotation marks.