Essay · The Scrub Mints · Aiken, South Carolina

The Rosemary That Isn't

On a family of small, stubborn, wonderfully scented shrubs that grow where almost nothing else will, spent two centuries refusing to keep a name, and have been living on the benches of one nursery in Aiken for the better part of forty years.

9 min read · By Fiona von Grey · Aiken, South Carolina

IA smell before a name

There is a kind of scent that belongs to heat. You notice it on a Mediterranean hillside at noon, or walking through a stand of pines after a dry week, or crossing a patch of Florida scrub in late summer when the sand is too bright to look at. The air itself seems to be seasoned. Most people put that smell down to the pines, and some of it is. A good deal of it, in the Southeast, comes from a set of small, twiggy, unassuming shrubs close to the ground: the calamints and the false rosemaries, the scrub mints.

Crush a leaf of Conradina canescens and you get something resinous and cool, close to rosemary with a eucalyptus edge, which is roughly what the chemistry would predict: the oil is rich in camphor and 1,8-cineole, the compound behind the medicinal clean of eucalyptus. Crush Georgia savory and the smell is sweet, frank mint. 'Desi Arnez', a foundling of mixed parentage, gives off a clean peppermint that people tend to go back for a second time. Scarlet calamint smells spicier and less sweet, as if someone had added pepper to the mint. Wild pennyroyal, Piloblephis rigida, which flowers in late winter, is the sharpest of the lot, pure bright mint from stiff little needles.

Cumberland rosemary, Conradina verticillata, is the one that stops people. The needles smell so much like the kitchen herb that the first question is always about cooking. In 2022 a team at the University of Tennessee put the scent through a proper analysis for the Journal of Agricultural and Food Chemistry, and found what you would expect, 1,8-cineole for the eucalyptus note and eugenol for a whisper of clove. They also found the single most potent odorant in the mix was a compound called 1-octen-3-one, which on its own smells of mushrooms and damp earth. The most rosemary-like plant in the Southeast owes a good part of that character to a note of forest floor. I find that very cheering. Nothing is quite as simple as the label.

Why a shrub on dry white sand would load the leaves with volatile oils is a reasonable question, and the honest answer is that the reasons are probably several. Aromatic oils make foliage unpleasant to many grazing animals, which may be part of why deer so often walk past these plants. They may help a leaf cope with heat and glare. And in gray false rosemary, the same chemistry appears to discourage other plants from growing too close, including the grasses that would otherwise carry fire into the mound. Whatever the mix of purposes, the effect for a gardener is the same. These are shrubs you plant for the air around them.

The most rosemary-like plant in the Southeast owes part of that character to a note of forest floor.

IINames that would not sit still

If you have bought one of these plants anywhere other than here, there is a fair chance the label said Calamintha, or Satureja, or simply savory. None of those labels was wrong at the time it was printed, which is the whole trouble.

Scarlet calamint makes the point better than any other. The plant was first published in 1825 as Cunila coccinea, a name drawn from a genus of American mints. Over the following decades the same species was filed under Melissa, the lemon balms, under Gardoquia, under Calamintha and under Satureja, before Otto Kuntze moved the plant into Clinopodium in 1891. The problem was never the plant. The features that were supposed to separate those genera, the shape of the calyx, the form of the leaf, where the plant grew, simply blur into one another when you look across enough species, and later molecular work has tended to confirm that the old lines do not hold.

Woodlanders began growing the southern calamints in the 1980s and called them Clinopodium from the start, and went on doing so through the long stretch when most references preferred Calamintha. That was less a scientific position than a small nursery's stubbornness, but the name has come round, and we will admit to some private satisfaction.

The argument is not finished. Kew and the federal ITIS database now sink Georgia savory, Clinopodium georgianum, into Clinopodium carolinianum, a name from 1768 with priority if the two are one species. The regional flora and the state heritage programs keep georgianum. Kew also folds two named false rosemaries into Conradina canescens, while the Fish and Wildlife Service, citing genetic work, keeps one of them, short-leaved rosemary, separate and federally endangered. A plant can be a species in Washington and a synonym in London on the same afternoon.

Wild pennyroyal has had the busiest career of all. George Bentham published the plant as a Satureja in 1834, crediting the name to William Bartram. Rafinesque gave the plant a new genus, Piloblephis, in 1838. Kuntze, tidying as ever, moved the species into Clinopodium in 1891, and John Kunkel Small renamed the plant Pycnothymus rigidus in 1903, which is what our own catalog called the plant for decades. Piloblephis has since won out. One species, four names, and not a single change in the plant.

The most useful name of all may be the newest and least formal. In 2024 a team from the Soltis laboratory at the Florida Museum of Natural History, reading the group's DNA, described a Southeastern “scrub mint clade”: Dicerandra, Conradina, Piloblephis, Stachydeoma and four species of Clinopodium, a single branch of the mint family that grew up on sand. The southern calamints and the false rosemaries, it turns out, were close relatives all along. The labels just took a while to agree.

And then, of course, there is true rosemary, the herb every false rosemary is named against. In 2017 botanists moved Rosmarinus officinalis into Salvia, so the kitchen plant is now properly Salvia rosmarinus, a sage. The false rosemaries of the Southeast have spent a century and a half being compared to a genus that no longer exists. They seem to have taken the news well.

IIIThe country of white sand

The Southeastern sandhills are old shorelines and dunes left behind inland as the sea retreated, long ridges of deep, pale, nutrient-poor sand running from the Carolinas through Georgia and down the center of Florida. Aiken sits on the northern part of that country, and anyone who has dug a hole in town knows it. Rain goes through the ground here like water through a sieve. Organic matter breaks down almost as fast as you can add it. For most of the plants people buy at a garden center, it is about as hostile a soil as the region offers.

For the scrub mints it is home. Historically these ridges carried open longleaf pine over wiregrass, a savanna kept open by lightning fires that came through every few years, and the Florida Natural Areas Inventory puts the natural return interval in sandhill at one to three. Fire cleared out the oaks and brush and let the small sun-loving shrubs and wildflowers flourish at ground level. Gray false rosemary burns to the ground and comes back from seed. The whole flora is arranged around being burned regularly and recovering.

That arrangement has not fared well. Longleaf once covered something on the order of 90 million acres of the Southeast. By the turn of this century perhaps three million acres were left; restoration has since pushed that past five million, which is real progress and still less than six percent of the original. What was not cleared was often simply protected from fire, which in this landscape is a slow way of losing the ground layer. Along the Florida ridges a great deal of the scrub went under houses and roads. The large-flowered scarlet calamint of east-central Florida grows, or grew, squarely in the path of greater Orlando.

Not every scrub mint keeps to the sandhills. Scarlet calamint and Ashe's calamint grow on the wind-blown white sand of the Ohoopee dunes in Georgia, one of the stranger small landscapes in the state. Gray false rosemary holds the back slopes of the Gulf Coast dunes. And Cumberland rosemary went somewhere else entirely, up onto the Cumberland Plateau of Tennessee and Kentucky, onto river bars of sand and cobble that floods scour clean and summer bakes dry. Fire, flood, shifting sand: the agent differs, but each of these plants has settled on ground that something keeps open.

IVHanded along, and handed back

A good nursery keeps records, and a very old nursery keeps stories, and the scrub mints have given Woodlanders more than their share of both.

In September 1990 Bob McCartney of Woodlanders was in the Etonia scrub of Putnam County, Florida, and found a false rosemary that did not look like any of the others: bigger, with small oval leaves where the rest of the genus carries needles, and large pale lavender flowers. The plant was a new species. Robert Kral and McCartney described Conradina etonia in the journal Sida the following year, and in 1993 the Etonia rosemary was listed as federally endangered, known today from three populations within a few miles of one another. We cannot sell the plant. The record of finding the species is one of the things this nursery is proudest of.

Other plants arrived by the more ordinary route, which is friendship. A yellow-flowered scarlet calamint came from Ken Wurdak, who found the plant in Tattnall County, Georgia; we lost our stock over the years and got the clone back from Mike Creel, who had been given starts by us long before. That is 'Ohoopee Yellow'. A purple-flowered hybrid between Ashe's calamint and Georgia savory appeared as a chance seedling in the Seaford, Virginia garden of the writer Pamela Harper, and we introduced the plant. 'Amber Blush', found wild in Santa Rosa County, Florida, and introduced by Plant Delights, came to us from Rick Lewandowski, one of the three who found the plant. Two low conradinas collected along the Styx River in Alabama went out from here as 'Low Gray' and 'Low Green', and we no longer have either. If you do, we would love to hear.

And then there is 'Desi Arnez', a seedling that came up in Robert Mackintosh's garden with no one having arranged the match. The most likely parents are Georgia savory and a false rosemary, members of two genera that very rarely cross. By our own account Gail Barton of Flowerplace Plant Farm in Mississippi did much to spread the plant around, and Richard Lowery named the seedling after Desi Arnaz, which for an improbable partnership that turned out wonderfully seems about right. Somewhere between the naming and the labels, the spelling shifted, and the plant has answered to both ever since.

Rare plants mostly survive this way. Not in a single great collection, but scattered through gardens and small nurseries, passed from one grower to another, lost in one place and found again in another. A nursery is only one link in that chain. We intend to be a sturdy one.

Lost in one place and found again in another: that is how rare plants mostly survive.

VWhy grow them now

The practical case is strong and getting stronger. Southern summers are hotter and the rain less dependable than they were when Woodlanders started, and gardeners across the region are giving up on thirsty lawns and borders that need a hose every other evening. The scrub mints ask for sun, sand and very little else. Established plants go through a dry August without a drink. They want no fertilizer. Deer usually leave them alone. And scarlet calamint in fall flower is as good a hummingbird plant as the Southeast grows, in bloom right as the ruby-throats come through on the way south.

There is a second case, quieter. Several of these species are rare in the wild for reasons no gardener can fix: a river dammed, a ridge paved, fire kept off a pineland for fifty years. What a gardener can do is keep the plants in cultivation, so that the species exist in more than a handful of places, and so that nobody has any reason to go and dig one out of the wild. Nursery-grown plants take that pressure off. Where the law allows us to sell one, we will. Where the law does not, as with the federally listed false rosemaries outside their home state, we will explain why and keep growing the plant anyway.

The simplest case is the one you make yourself, with your hand, on a warm afternoon. Plant a few of these where you will brush past them, and the smell of that white-sand country will follow you up the path.

Further reading on The Node

Every species and selection mentioned here, with availability and advice on choosing, is in the new field guide to the scrub mints. For planting them well, read Gardening in Sand. For the story of Cumberland rosemary and the law, Cumberland Rosemary, and Why We Only Sell One in South Carolina. And for the family of true rosemary, now a sage, The Sultan of Salvia.