Here we are at the half-way mark of summer. I don’t know about your garden, but mine is teetering on the brink of the slide into the August doldrums. At this perilous point in the season, I am ever-grateful for the hardy geranium, whose many species provide dependable cheer in the garden all summer long.
I am not talking about the flowerpot geranium, which is now included in the Pelargonium genus. The flowerpot geranium, introduced into Europe in the 17th century, was originally thought to have been related to the native geraniums of the northern hemisphere, and accordingly Linnaeus classified both types as belonging to the Geranium genus.
In 1789, a French botanist named Charles L’Heritier de Brutelle reclassified the flowerpot geranium as a Pelargonium. I confess I have an unpleasant association with the pelargonium, because my mother always dragged her pots of so-called “geraniums” inside for the winter, where they grew long and scraggly, more dead than alive, occasionally producing a spindly red flower that somehow justified their overwintering.
One of the many things I love about plants is their quirky nomenclature. According to the Royal Horticultural Society (RHS) Dictionary of Gardening, a four-volume tome that I received as a birthday present this year from dear gardening friends, the ancient Greek pharmacologist Dioscorides named the plant geranion after Greek geranos, which means crane. This was evidently due to the appearance of the fruit capsule and upwardly pointing stigma, which some say resembles a crane’s head and beak. That allusion has stayed with us, and explains why hardy geraniums are commonly called cranesbills.
There are 422 species of hardy geranium in all. They are true stalwarts, filling multiple roles in the garden from star players to supporting cast. They are usually left alone by rabbits and deer as well as slugs, and they provide nectar and pollen to pollinators. Their delicately veined flowers, for example, deep red on pale pink, or purple on white, reward close inspection. Their attractive palmate foliage comes in a variety of shapes, sizes and colors.
For the mixed border, the hybrid cultivar Rozanne is a must-have. Named for British horticulturalist Rozanne Waterer, who cultivated (and presumably watered) the plant with her husband George, it has deep-green, slightly marbled leaves and prolific periwinkle-purple flowers with white eyes. It continues to thrive when other plants are past their prime. Mine looks wonderful cozied up to a peach-colored Drift rose. It spreads happily but is not thuggish. A winner of the Royal Horticultural Society’s (RHS) Award of Garden Merit, it seems to grow anywhere there’s some sun and un-soggy soil. Garden centers also carry other popular hybrid cultivars such as Johnson’s blue and Wargrave pink (another RHS award-winner) but in my experience these are less reliable.
At the thug end of the geranium spectrum is the species macrorrhizum, or bigroot geranium. But it’s a thug I’m very happy to have in the garden. It is a dependable groundcover for dry shade, spreading its wave of green, pungently scented leaves freely. When it has spread too far I just yank it out and what’s left is none the worse for wear. It sports pale to bright pink flowers, depending on the variety, early in the summer. It can get tattered-looking in hot, humid weather and benefits from a haircut with garden shears. Within a couple of weeks it looks good again, and the foliage turns a lovely red in the fall.
Another popular ground-covering species is G. sanguineum, or bloody cranesbill. Its dense mounds of small leaves — about an inch across — are dotted with cheerful flowers ranging in color from magenta to nearly white. The cranesbill effect is especially notable on this variety and provides an interesting display once the flowers are spent.
One of my favorite species is the G. phaeum with its plummy purple flowers and green leaves with purple splotches that look as if they were tie-dyed. It doesn’t spread much — at least not in my garden — but it’s an attention grabber. Its common name is “mourning widow,” according to the RHS Dictionary of Gardening, Other sources call it “dusky cranesbill” but I prefer the dramatic British name. It’s not just a widow, but a mourning one, still in her black widow’s weeds. What a weighty name for a poor flower to carry!
I’m always delighted by the serendipity of gardening. The Geranium nodosum (knotted cranesbill) magically appeared in my garden several years ago. It must have hitched a ride with another plant given to me by a friend. A native of Southern Europe, its tiny lavender flowers and delicate pale green leaves distinguish it from other, bolder geraniums. It blooms faithfully all summer long in a dry, shady part of the garden, seemingly impervious to extreme conditions. Speaking of intriguing names, I’m not sure why it’s called “knotted.” Perhaps someone can fill me in!
Mickey Rathbun is an Amherst-based writer. Her latest book, The Real Gatsby: George Gordon Moore, A Granddaughter’s Memoir, was published in 2024 by White River Press.