Botanical Nomenclature 101

Magnolia grandiflora • Photo by Neil HodgesAlthough New Year’s resolutions are made to be broken, why not resolve to become more familiar with botanical or horticultural designations of plants that we grow or wish to grow?

Why bother?

For starters, it’s useful for precise identification, for information about growth habit and habitat preference, and for bloom expectations.

Though written in Latin, it is often possible to tease out the meaning due to some similarity to the English equivalent. That’s not always true, but it helps advance your general gardening prowess just to try. At the risk of preaching to the choir, it is well known that the binomial system of naming plants and animals was devised by Swedish physician/botanist Carl Linnaeus and published in 1753 in “Species Plantarum.”

Binomial means two names, in this case “genus” and “species.” A “genus” is a group of closely related species that share common ancestry and have certain characteristics in common. The word genus is familiar through the terms “genetics” and “genes.”

The second word, “species,” means that its members will be essentially alike in the great majority of their most important characteristics. The genus word is always capitalized, the species word is normally not. The species word is meant to give some horticultural, and therefore useful, information about the plant. For instance, “Magnolia grandiflora” tells us that it produces large flowers. If the word were “grandifolia,” it would imply large leaves. Perhaps it helps to quote the brief definition written by prominent 20th century botanist L.H. Bailey in his epic work “Hortus:” “A kind of plant or animal that is distinct from other kinds in marked or essential features, that has good characteristics of identification, and that may be assumed to represent in nature a continuing succession of individuals from generation to generation.”

Still with me? There’s more. The third word of especial importance to gardeners is the “cultivar” name, designating a plant that has been hybridized or specially selected by man’s efforts to feature more appealing qualities.

Those include longer and/or better bloom, color, cold hardiness, form or height, fragrance and many other traits deemed desirable for garden or landscape use. This name is an invented appellation designed to give more information and to attract attention, i.e., Hydrangea macrophylla Blushing Bride. Some illustrative examples of species names follow: sempervirens – evergreen; repens – creeping; spreading by runners (watch out!); procumbens – prostrate; pendens – pendent; compactus – compact in form; confertus – crowded; communis – growing in common, general; canariensis – from the Canary Islands; japonica – from Japan; indica – from India or the Indies or the Far East; chinensis or sinensis – from China; splendens – speaks for itself.

It is not necessary to learn the exact meaning of every name, but it is possible to pick up bits and pieces of useful information along the way, which can’t help but enhance our pleasure and success in the fascinating pursuit of gardening.