Verbena hastata 'Rosea'

Ok, all (ten) of you who find this stuff interesting, it’s time for more fun with botanical nomenclature. Now that White, Black, and Shades of Gray are out of the way, let’s move on to the names of more exciting colors.

Red Ahead

From shocking to sultry, reds add a distinctive feature to the flowers,  foliage, and fruits of many plants. There are more names for different shades of red than for many other colors, for a very interesting reason: According to On Being Well Red, the Romans based their color names on the various dyes they could produce, and apparently there were quite a few ways to produce reds.

The most common ways you’ll find red appearing in a plant name is as rubra, ruber, rubrum, and rubens. There’s also the closely related rubella (-us, -um) and rubicunda (-us, -um), as well as rubescens and erubescens (being or becoming [blushing] red). All of these are based on rubrica, the term for a reddish soil. Examples abound here:

• Atriplex hortensis var. rubra (red orach) and Imperata cylindrica ‘Rubra’ (Japanese blood grass), both shown above, with leaves that are red or reddish
• Centranthus ruber (red valerian) and Trifolium rubens (red feather clover), with reddish flowers
• and Crinum erubescens (swamp lily), which usually has reddish stems

Another basic red is rutilans, as in Salvia rutilans (pineapple sage, which is now technically Salvia elegans ‘Scarlet Pineapple’, shown at left).

You may also see the prefix “erythro-”, as in:

• the genus Erythrina (often called coral trees or flame trees)
• the red-plumed Amaranthus hybridus var. erythrostachys
• and the red-stemmed Acer pensylvanicum ‘Erythocladum’ (moosewood maple)

If you vampire fans can remember that exsanguinate means “to drain (or be drained) of blood,” it’s no trouble to connect sanguinea (-us, -um) to blood-red. Examples in the plant world include:

• Heuchera sanguinea (coralbells)
• Cornus sanguinea (bloodtwig dogwood)
• Rumex sanguineus (bloody dock, at right)
• and Geranium sanguineum (bloody cranesbill)

Atrosanguinea (-us, -um) refers to an even deeper red, as in the flowers of Cosmos atrosanguineus (chocolate cosmos) and Potentilla atrosanguinea (ruby cinquefoil).

Cruenta (-us, -um), too, refers to blood-red. Amaranthus cruentus (red amaranth) is one example.

For scarlet-red, there’s coccinea (-us, -um); think of:

• the flowers of Salvia coccinea (Texas or hummingbird sage, above)
• the berries of Pyracantha coccinea (scarlet firethorn)
• and the fall color of Quercus coccinea (scarlet oak)

For deeper red, there’s atrococcinea (-us, -um), as in Centranthus ruber ‘Atrococcineus’ (the form of red valerian with darker red flowers).

The backstory for the word crimson is complicated, but if I’ve figured it out right, it has to do with the dye made from a scale insect (Kermes vermilio). In plant names, we have carminea (-us, -um), carminata (-us, -um), and kermesina (-us, -um), as in Deutzia x rosea ‘Carminea’ (pink deutzia) and Clematis ‘Kermesina’.

The Latin miniata (-us, -um), from minium, referring to the pigments red lead or vermilion (ground-up cinnabar), appears most recognizably in Clivia miniata (kaffir lily).

I hardly need to explain cardinale or cardinalis, as in Lobelia cardinalis (cardinal flower, right).

Fiery reds are indicated by flammea (-us, -um) and ignea (-us, -um), as in Rhododendron flammeum (Oconee azalea) and Cuphea ignea (cigar or firecracker plant, below).

For rosy reds, there’s good old rosea (-us, -um): think of Coreopsis rosea (pink tickseed), Catharanthus roseus (rosy periwinkle), and Rhododendron ‘Roseum Elegans’, to name just a few examples.

When you drift towards flesh-pink, there’s carnea (-us, -um) and incarnata (-us, -um), as in the words carnal (of the flesh or body) and incarnate (in the flesh). In the plant world, it refers to the flower colors of Aesculus x carnea (red horsechestnut), Erica carnea (winter or spring heath), and Asclepias incarnata (swamp milkweed, at left).

Orange, Etc.

As reds get mixed with a bit more yellow, colors start drifting into the orange range. This is also a good place to cover rusty and coppery colors.

Reddish brown colors are indicated by rubiginosa (-us, -um) and the prefix “rufi-”: examples include Ficus rubiginosa (rusty fig, with reddish brown leaf undersides) and Acer rufinerve (redvein maple).

For brick-related colors, there’s lateritia (-us, -um) and testacea (-us, -um), as in Papaver lateritium (Armenian poppy, which is distinctly orange in bloom) and Carex testacea (orange New Zealand sedge, with orangey brown foliage).

Ferrum, the Latin word for iron, appears in ferruginea (-us, -um): think of Digitalis ferruginea (rusty foxglove, right).

It makes sense that cuprea (-us, -um) would indicate coppery colors. The most obvious example is the Fagus sylvatica Cuprea Group (copper beeches).

“Tawny” colors – anywhere in the range of brownish to reddish yellows (essentially, shades of orange) are indicated by fulvus (-us, -um). Hemerocallis fulva (commonly known as tawny daylily or ditch lily) is one well-known example; Iris fulva (copper iris) is another.

If you’ve ever grown calendulas or pot marigolds (Calendula officinalis), it’s no stretch to remember that calendulacea (-us, -um) refers to shades of calendula orange or flame colors, as in Rhododendron calendulaceum (flame azalea).

And for a basic orange, there’s aurantiaca (-us, -um): Agastache aurantiaca (orange hummingbird mint), Hieracium aurantiacum (orange hawkweed), and Ilex verticillata var. aurantiaca (orange winterberry holly) are just a few examples.

Gold Standards

Yellow-related terms pop up a lot in plant names, most often in connection with flower colors or markings by sometimes in the leaves, bark, or even roots.

If you spend any time at all looking at plant names, you’ve seen aurea, aureus, and aureum (referring to gold) plenty of times, especially in relation to foliage. Examples abound:

• Catalpa bignonioides ‘Aurea’ (golden catalpa, right)
• Humulus lupulus ‘Aureus’ (golden hops)
• Origanum vulgare ‘Aureum’ (golden oregano)

The closely related aureola (-us, -um) doesn’t appear in nearly as many names, but it gets plenty of exposure in Hakonechloa macra ‘Aureola’ (golden Hakone grass, below).

Aurata (-us, -um) also fits in this group: you see it in Lilium auratum (gold band or golden-rayed lily).

The prefix “aureo-” belongs here too, and it appears in a good many names, including Phyllostachya aureosulcata (yellow-groove bamboo) and Lonicera japonica ‘Aureoreticulata’ (gold-net honeysuckle, at left), to give just two examples.

Another group of terms that often appear in yellow-related names includes flava, flavus, and flavum, as well as flavula (-us, -um), flavens, flavescens and the prefix “flavo-”. A few examples include Thalictrum flavum ssp. glaucum (dusty yellow meadowrue, left) and Hosta tokudama f. flavocircinalis (a hosta with yellow-edged leaves).

Yet another common group of terms for yellow includes lutea, luteus, luteum, luteo, luteola (-us, -um), and lutescens. Think of:

• Asphodeline lutea (yellow asphodel, right) or Corydalis lutea (yellow corydalis)
• Trillium luteum (yellow trillium)
• Ilex aquifolium ‘Fructo Luteo’ (yellow-fruited English holly)
• Reseda luteola (weld, the source of a yellow dye)
• and yellow-flowered Rhododendron lutescens

Chrysos, for gold, gives us the final main group of yellow-indicating terms: chrysantha, chrysanthus, chrysanthum, and the prefix “chryso-”, as in chrysographes (literally “gold writing” but usually meaning gold markings). A few examples:

• Aquilegia chrysantha (golden columbine)
• Crocus chrysanthus (golden crocus, below)
• Iris chrysographes (gold-vein or black iris)
• Chrysopsis (goldenaster)
• and the obvious Chrysanthemum (“golden flower”)

The citrus fruit known as citron (Citrus medica) has a greenish yellow rind, and it gives its name to a greenish yellow or lemon-yellow color as citrina, citrinus, and citrinum, most obviously in Hemerocallis citrina (citron daylily).

Crocus and crocum, for saffron, give us crocea, croceus, and croceum, as in the Iceland poppy Papaver nudicaule var. croceum.

No need to explain the connection between sulphurea/sulfurea (-us, -um) and sulfur-yellow, as in Hedera hibernica ‘Sulphurea’ and Epimedium  x versicolor ‘Sulphureum’.

And one more for the yellows: the prefix “xantho-”, as in Xanthorhiza simplicissima (yellowroot, above) – which also has great yellow fall color.

Next time, the rest of the rainbow, plus some bonus color-related terms.