Error is a hardy plant,” Martin
Farquhar Tupper wrote in his long-ago popular “Of Truth
in Things False” (1838). His sage metaphor seems
especially applicable to so-called geraniums, enormously
popular plants bearing an erroneous common name.
Although these supposed geraniums are actually
pelargoniums, the widespread misnaming of them has
proved to be as hardy as a lawn weed. Just mention the
word “geranium” and typically the pelargonium impostor
comes to mind.
This misunderstanding began in the
1600s, when the Dutch East India Company first imported
South African pelargoniums to Europe, and this
widespread misperception isn’t likely to change anytime
soon. Even books about these perennials dodge the word
“pelargonium” on their covers. Instead, for example,
their titles read Geraniums: The Complete
Encyclopedia and Scented Geraniums, a
marketing pattern that might appeal better to some
potential buyers but hardly helps to set the record
straight in gardeners’ minds.
In fact, this
misidentification remains so strong that the reality of
true geraniums can come as a surprise to some gardeners.
True geraniums, the woodland natives also known as
cranesbills, do not look like pelargoniums even though
both genera belong to the family Geraniaceae. True
geranium flowers, for instance, usually feature floral
forms similar to primrose blooms, whereas pelargoniums
erect spikes tipped by clusters of flowers somewhat
reminiscent of winged insects, particularly butterflies.
Whatever they have been called, pelargoniums have
remained popular garden selections for centuries. At
first, early-European gardening interest focused on the
wild species of these plants, especially Pelargonium
zonale. By the middle of 18th century, however,
P. zonale hybrids dominated the garden scene.
hybrids continue to star as bestsellers, while the more
basic native pelargoniums have slipped into obscurity.
“Species pelargoniums,” as collectors refer to them, are
the plainer ancestors of today’s fancy hybrids. Although
about 200 species pels exist, many of them tend to be
hard to find commercially because their marketing value
remains limited. With the exception of those valued for
their scent, species pels primarily fascinate gardeners
on the lookout for uncommon plants. I have occasionally
wondered, only half-seriously, whether these sidelined
“wallflowers” perhaps attract gardeners who feel sorry
for “rejected” plants.
Species pels often do look
like plants in need of rescue and tender-loving care.
Their foliage tends to be sparse with an open overall
form. Sometimes, as with lavender-flowered P. hirtum,
they give the impression of a bungled parsley imitation.
Likewise, the spiked flower heads of species pels
hardly make a case for them. Their floral display
remains smaller and less abundant than those produced by
contemporary floriferous pel hybrids. Even so, for some
gardeners this very difference accounts for one of the
charms of species pels, proving that tiny flowers
sometimes appeal to humans as much as to their
Although species pels are not common
at local nurseries, their seeds can be purchased through
internet contacts. The most available species include:
P. acetosum, a sorrel-like shrub ornamented by
clusters of two to seven salmon-pink flowers; P.
carnosum, a bonsai-like succulent with small
cream-hued blooms highlighted by pink nectar guides;
P. cordifolium, a heart-leafed plant bearing cute
lavender blossoms with wide upper petals adorned with
dark nectar guides; P. echinatum, a
low-growing, thorny succulent with fuzzed leaves and
white-to-pink flowers with a heart-shaped red spot;
P. graveolens, a rose- or lemon-scented two-footer
with small, purple-spotted, pink-white blooms and
trailing ruffled leaves; P. multicaule, a
creeping, short-lived perennial with tiny pink,
magenta-striped blossoms; P. salmoneum, a
sandy-soil, part-shade perennial with salmon-hued
flowers; P. suburbanum subsp. suburbanum,
a fast growing, mat-like plant with long-lasting pink
blooms; P. tetragonum, a creeping
square-stemmed succulent with red-margined leaves and
white-pink blossoms; and P. tomentosum, a
peppermint-scented trailer with tiny white flowers and
large velvety leaves.
Species pels divide into two types, succulent and
tuberous. Both store water, enabling them to withstand
periods of dryness. Both insist on rapidly draining,
compost-rich potting mixtures, and neither type
tolerates damp, rainy conditions. Morning watering
(without wetting their foliage) proves best, but only
when their soil feels dry. To avoid a judgment error, I
use an inexpensive water meter.
With thick stems
and fibrous leaves, the succulent-type pels can
withstand heat and direct-sun exposure better than the
tuberous type. Most of us grow tuberous pels, which
include the scented varieties. Some tuberous types
cannot tolerate too much humidity, while others struggle
in too much heat. To flower, however, pels require some
exposure to sunlight during spring and autumn, usually
their high-performance seasons. The tuberous types go
dormant during our summers, when they should be kept dry
and shaded. When dormant, they sometimes look like dead
sticks. All pels must be protected from frost by indoor
overwintering — also the best time to prune their
yellowing leaves and stalks.
For most Texans, the
prime seasons for pel performance can be compromised
when hot weather ratchets up much too quickly during
spring or lingers seemingly forever during autumn. On
the other hand, they perform wonderfully during winter
in South Texas.
Our pels do best, then, when
allowed direct-sun exposure only during the morning
followed by bright afternoon shade. All-day dappled
light — such as beneath live-oak canopies — also works.
Sinking their pots into the ground or a mulch mound
reduces the desiccating impact of warm wind. Adding an
inch-deep layer of pine-bark mulch around each buried
pot helps keep tuberous-pel roots cool, and these roots
actually prefer to be moderately pot-bound. Pel roots
rot when overwatered. In Texas, however, hydrating them
thoroughly when truly dry and feeding them lightly after
summer dormancy aid their performance. As strange as it
might seem, regular irrigation and feeding usually
shorten the life of pels.
Today’s gardeners find the
showy zonal, angel, ivy-leaf and regal selections far
more alluring than species pels. These newer jazzy
selections stem from decades of selectively
crossbreeding the plainer species pels for special
At least today’s retailed scented pels
often remain fairly close to their more basic species
lineage. Some actually are simply species pels, such as
orangey P. graveolens ‘Citriodorum’ and piney
P. denticulatum. Others are cultivated
varieties of species pels, including P. capitatum
‘Pink Lemonade.’ Like species pels, today’s scented
selections tend to bear fewer and tinier flowers than
the fancier pel hybrids. To make up for less showiness,
however, some scented pels produce a variety of
appealing fragrances inherited from their wild
ancestors, which (incidentally) exhibit a decent level
of heat tolerance on their own in nature.
frequently associate scent with flowers, although in
fact foliage often releases the volatile chemicals we
regard as fragrance. That’s the case with pels, which
possess aroma-emitting leaves. The selections retailed
specifically as “scented-leafed” belong not to a botanic
category but to an artificially designated marketing
group defined solely by fragrances we favor.
These preferred fragrances include citrus, peppermint,
rose, cinnamon, nutmeg, ginger, peach, apricot, apple,
strawberry, coconut, pineapple and even celery. There
are, as well, other pungent and not quite identifiable
scents — some considered distinctly unpleasant.
Interestingly, people regularly differ about what smell
they detect despite a market tag informing them what
fragrance they should identify.
possess tiny hollow glandular hairs (trichomes) with
fragile tips that easily break when touched or brushed.
Once broken, these hair tips secrete oil from their base
located inside the disturbed leaf. As this oil
volatilizes, we perceive it as fragrance. This oil
provides sunscreen for pel leaves and also helps pel
foliage to retain moisture during hot days.
Unpleasant-tasting, this oil certainly deters predation.
So, with pels as with rosemary and agastache
(hyssop), the biological utility of unpleasant-tasting
leaf oil is hardly mysterious. On the other hand,
precisely what advantage leaf scent gives a
plant remains uncertain. Volatilizing chemicals released
from distressed leaves (research shows) chemically
signal nearby plants of the same species to adjust their
own enzymes (usually toward bitterness) in readiness for
attack. Possibly, too, as in the example of our native
lantana, leaf odor is designed to deter smell-sensitive
animals from sampling the plant, leaving the actual oily
bad-taste experience as a back-up (rather than a
primary) disincentive. After all, it would be better for
a plant if animals walked away from it on first “stinky”
encounter rather than after taste-testing some foliage
before giving up on it as a food source. No damage is
better than some damage.
Why scented pels have
developed so many different fragrances remains much more
puzzling. Maybe unique scents attract specific
pollinators or maybe they summon territorial insects,
such as ants, to aid the disturbed plant by dispatching
a munching invertebrate or warding off some larger
intruder. Whatever the reason, pel scent has obviously
also enticed gardeners, the plant’s ultimate territorial
guardians (so the speak). After ornamenting late-winter
and early-spring home landscapes, long-lasting
scented-pel foliage has been used medicinally or tucked
into sachets and potpourris. Besides some culinary
value, scented pels also contribute fragrance to a night
garden during warm evenings.
Unfortunately, not all scented pels
live up to the fragrance promised on their market tags.
Actually, many are inadequately labeled — either
misnamed or renamed to increase commercial appeal. A
selection’s exact parentage tends to remain obscure. So
much crossbreeding (hybridization) has occurred over so
long a period that it is now very hard to classify many
of the marketed pels.
Also disconcerting, a
particular pel can produce more than one fragrance and
can also vary in intensity of aroma. Plant fragrance
tends to become strongest in warm temperatures. As a
result, for example, a scented species pel such as
P. denticulatum might smell (pleasantly) like
balsam/pine or (less pleasantly) like Pine Sol,
depending on the weather. So, apparently, savvy
collectors of scented pels shop on warm days and gently
rub a leaf to sample its perfume before purchasing a
plant. For them the rule of thumb is “sniffer beware,” a
gardening version of caveat emptor (buyer
While only individual preferences can
determine which plant will delight, some pels have
proven to be widely reliable based on their promised
scent. That’s the case with aptly named ‘Old Fashioned
Rose,’ ‘Pink Lemonade,’ ‘Ginger Frost,’ ‘Chocolate
Mint,’ ‘Apple Cider,’ ‘Almond,’ among others. Whether
‘Gooseberry Leaf’ smells like a peach or ‘Paton’s
Unique’ smells like an apricot can spark a patio
discussion — the sort of conversation that scented pels