It’s as close to a gardening craze as you’re likely to find, this sudden interest in genuine geraniums. Virtually unknown in Southern California, and seldom seen until a few years ago, avid gardeners are talking about them, and nurseries seem to have a new kind every week.
“It’s the flavor of the month” is how Robin Parer, who runs a geranium-only nursery in Northern California, explains their sudden popularity. She’s had many Southern Californians make the trek north to buy plants at her nursery, Geraniaceae (open only by appointment, call (415) 461-4168, no mail order).
True geraniums--plants with the botanical name of Geranium --are quite different from what we commonly call “geraniums.”
The pretenders, the Martha Washington, ivy, zonal and common “geraniums,” are technically pelargoniums and are native to Africa, while the true geraniums are found growing in the wild worldwide.
The confusion over names began in 1753 when botanist Carolus Linnaeus lumped the two together as Geranium in his “Species Plantarum.” When later botanists noted the obvious differences (one is that geraniums have symmetrical flowers while pelargoniums have asymmetrical), they separated them into Pelargonium and Geranium , though they are still in the family. But the damage was done and persists to this day.
While it is hard to beat a pelargonium, especially in a pot, the genuine geraniums also have their place in the California garden.
The place for the most commonly available, Geranium incanum, is unquestionably on slopes or in planters, where it can tumble and spill, if you listen to landscape architect Jana Ruzicka.
She used it as a water-thrifty ground cover in a Corona del Mar garden just blocks from the seaside bluffs, where they swirl and foam around other plants--a ‘Gruss an Teplitz’ rose, sea statice, Santa Barbara daisies, tulhbagia and valerian.
At a nearby condominium, they bubble out of a planter box on a balcony railing. In the misty ocean air, the flowers are especially vibrant, though they look nearly as good in the garden of Anne Williams in much drier (and hotter) Glendale.
Williams has grown all of the true geraniums she can lay her hands on, though it is only a fraction of what’s out there. They are numerous enough to have inspired books on them alone (two of the best are “Hardy Geraniums” and “The Gardener’s Guide to Growing Hardy Geraniums,” both English, though available here from Timber Press; for information, call (800) 327-5680).
Most of the true geraniums are small plants with smallish flowers. They are almost wildflowers, and in fact, many are, including one named G. californicum that grows in the San Bernardino Mountains.
Most have a brief, springtime flowering period. On the other hand, they have virtually no problems with pests or diseases and many will flower in some shade, definite pluses.
But don’t expect the punch of a pelargonium, these are what Parer calls “linking, filler plants,” best used in that space between other bolder plants in the garden.
G. sanguineum tops Williams’ list of personal favorites because it’s so easy to grow. It finds its own place among other low plants, interweaving with them--a perfect filler along a path or in the front row of a flower garden. It almost disappears for the winter, but from early spring on, there is a steady succession of nearly neon flowers, a shade of magenta purple.
One variety, lancastrense , has soft pink flowers for gardeners who are less gutsy with color, and it stays as a small spreading mat only inches tall.
Williams thinks the place for geraniums is in front of or even under roses because they can take the watering roses get and a smattering of shade, and they help hide the rose’s knobby knees.
G. macrorrhizum is her favorite for this use, a dense foot-tall ground cover with flowers held well aloft.
Landscape designer Christine Rosmini has found that it even flowers in a half-day of shade. She has used it as a small-scale ground cover under tall trees in a number of gardens. Parer says it will grow under oaks with little water (important for the health of the oaks) and that deer don’t eat it. There are several kinds, with white, pink or deep rose flowers.
Williams doesn’t recommend the English favorite named ‘Ballerina,’ which has elegant veining on the flowers, but prefers the similar ‘Lawrence Flatman,’ which does fine in our climate.
Others that have thrived in her garden include G. endressii ‘Wargrave Pink,’ the hybrids ‘Claridge Druce’ and ‘Biokovo,’ and the pearl-gray blue of ‘Mrs. Kimball Clark.’
‘Biokovo,’ in particular, seems to be a winner in Southern California. The flowers are a very soft pink, about an inch across and there are lots of them. In one Westside garden it blooms furiously from March into June, with a smattering of flowers through summer.
Parer says that ‘Claridge Druce’ will stand the heat of the Central Valley, and if the true geraniums are sensitive to anything, it is summer heat.
Some true geraniums come very close to true blue, a color gardeners are always searching for. England’s ‘Johnson’s Blue’ is the purest (though not as blue as some catalogue photos would have you believe), but it’s a poor grower in most gardens here. Williams has lost it several times.
Better suited to our climate is G. pratense , which grows to two feet or more with near blue flowers. Parer thinks it does best when it’s roots are kept cool, similar to clematis. It goes completely dormant in winter, so mark its place in the garden or you’ll dig it out come bulb planting time.
A more intense blue is found on G. ibericum . It too disappears for the winter. Less blue (more violet), but equally easy, is G. magnificum , a bushy perennial 18 inches tall.
G. maderense has its place staked out in the shade. It quickly forms a burly trunk, several feet tall, typical of many plants from the Madeira Islands. The dramatic foot-wide leaves look like green paper snowflakes.
After a couple of years in the garden, this biennial produces a single huge head, 2 1/2-feet wide, of small pink flowers. It then dies, although it usually reseeds.
It’s an unusual plant and won’t be found in the 1,290 pages of Hortus, the ultimate plant dictionary, nor, for that matter, at too many nurseries, but it and many genuine geraniums are out there, waiting for their place in the California garden.