Scientific names of organisms (plants, animals, etc.) are made up of two parts; a genus (plural: genera) name and a specific name. This is the basis of Binomial Nomenclature promoted by Linnaeus in the mid 18th century. Prior to this, names consisted of many words (polynomials), that often resemble short descriptive sentences. Scientific names are unique combinations of two words. A plant or animal can have only one valid scientific name and that name is used internationally. In contrast, a species can have many common names that are often local in origin and use.
The genus name is used for one or more populations of individuals that share a set of characters and origin. The genus name may be based (usually in latin form), on features, origin or a persons name. For instance, the bromeliad genus Lymania honors the 20th century family specialist Lyman B. Smith. Genus names are always capitalised.
The specific name is used for populations of similar individuals that are more concisely defined that share a more recent common origin. Species can vary, they are not carbon copies. As with genus names, specific names can be based on features, origin or persons. For example, the species Lymania azurea is based on the characteristic blue-colored flowers of this Brazilian bromeliad. Specific names are never capitalised. One can think of a binomial as a reversed order personal name:
Tillandsia ........ Smith
ionantha ........ Bob
Taken together these two names refer to a single individual species made up of similar, related individuals.
With a little knowledge of Latin (or Greek), and geography, one can often learn a few facts about the organism bearing a name, for instance that Aechmea mexicana grows in Mexico, Dyckia fragrans is fragrant and Pepinia holstii is named after a person named Holst.
Many of the plants at Selby Gardens lack common names because they are uncommon. Using the scientific name is much more exact and will lead to far fewer errors of communication.