by OCMGA Master Gardener Vicki Schilleman
When you hear ‘geranium’, I’m guessing you picture the beautiful annuals that are so beloved by northern gardeners. While I, too, love those gorgeous full heads of color all summer long, there is another geranium that I love as much: the ‘hardy geranium’.
Hardy geraniums are distant cousins of the tender plants known as geraniums. The irony is that the hardy plants have technical rights to the name (they belong to the genus Geranium), but it is the tender ones that most people think of when they hear “geranium”.
Technically, the familiar houseplants are not geraniums. They belong to the genus Pelargonium. But the confusion is natural. Both the hardy and tender versions belong to the Geraniaceae family, and they both used to be in the genus Geranium. Then the tender ones got split off into Pelargonium, but people kept right on calling them geraniums.
Pelargoniums were brought to Europe from South Africa early in the seventeenth century. They found immediate favor, but it was their scented leaves and not their flowers that caused the sensation. By the time they came to the U.S., more than a century later, Pelargoniums’ large clusters of bright red, orange, or hot pink flowers had taken center stage, a position they still hold; scented-leaved geranium fans are passionate, but a minority.
Meanwhile, back in the temperate British and American countrysides, numerous species of native Geranium, known to the populace as cranesbills, were finding their way into gardens. The cranesbills do double-duty, offering beautiful, long-lasting leaves as well as loose umbels of flowers in a wide range of pinks, blues, and purples.
You can usually tell these plants apart by general appearance: the leaves of Pelargonium are thicker than those of true Geranium, their flower stems are stiffer, and though individual flowers are smaller, they tend to be clustered more densely. And if you look closely at the individual flowers, you can usually see a tiny spur on the pelargonium flower stalk (geranium flowers don’t have them).
Color helps too: although both kinds might be white, plants in the genus Geranium come in purples, blues, and blue-tinged reds and pinks; those in Pelargonium may be true red, orange-red, pink, or orange, but they do not sing the blues.
Note: Wild geranium, also known as cranesbill, (Geranium maculatum) is a hardy perennial excellent for naturalizing, or filling in, under bushes or wherever there is dappled shade or part sun. The American native wildflower, with it’s flat, delicate-looking pink-lavender flowers and deeply notched foliage, is very easy to grow, ultimately reaching between 12 and 18 inches.