Giant carrion plant (Stapelia gigantea). Photo: World of succulents & 3.bp.blogspot.com
My wife pulled me away from my morning newspaper. “I think something has died in the plant room,” she complained. “It smells awful in there!” I dutifully rose to do my manly duty. (Putting out trash, unplugging toilets, picking up dead animals: we men well know what our role in a marriage is!)
I was assuming it was a mouse. Field mice sometimes move into our home in the fall and I figured our cat hadn’t caught that one and it had simply died of old age. But no mouse was to be seen … and the stench was truly awful.
Then I saw it: a huge star-shaped flower nearly 1 foot (30 cm) across on one of my plant shelves. My giant carrion flower (Stapelia gigantea) was in bloom! Of course, I’d seen the big onion shaped buds increasing in size over the last few weeks, but it’s bloomed before and I’d never really noticed the smell. But this time, it was pretty awful. Usually it was outdoors when it bloomed, so probably much of the odor wafted away in the wind, but this year I’d brought it in early because of the very cold fall weather. Also, it was a bright sunny day: it seems to give off very little scent in cloudy weather.
At any rate, the flower had to go … and the buds too (there were two more on the way). In warmer weather, I would have put it outdoors for a week or so (that’s about how long the flowers last), but it was too cold this year. So, I clipped them off and tossed them into the compost.
Next year, with a little luck, it will bloom earlier or the weather will be milder so I can leave it outdoors while it blooms.
Why Such a Stink?
The carrion flower has a good reason for producing its horrible stench! It does so to attract pollinators.
It grows in desert regions of South Africa where insect pollinators—bees, hoverflies, butterflies and their ilk—are in short shrift, but carrion flies are abundant. They lay their eggs on the rotting flesh of dead animals and their maggots feed on the carrion. So, the carrion flower has learned to attract its most likely pollinator by imitating dead flesh.
The petals are a pale ocher yellow like sunburned fat with transversal maroon lines like blood veins. The flower is thick and wrinkly like rotting flesh. The flowers are even surrounded by abundant long white hairs like animal fur. And then, there is, of course, the stink. Carrion flies come from afar to visit it.
While there, the flies crawl into the flower to lay a few eggs, picking up pollen as they go, then land on another open carrion flower, deposit the pollen, lay a few more eggs, then pick up more pollen and head off yet again.
The fly eggs hatch, but the maggots find nothing to eat and die, dropping to the ground where they decompose. The minerals they release then feed the plant, so the carrion flower is considered by some experts to be a passive carnivore (passive insectivore would be a more appropriate term).
It’s all very gruesome and fascinating, wouldn’t you agree?
Grow Your Own Stink
The giant carrion flower (S. gigantea) is only one of many plants bearing stinky flowers in the genus Stapelia, although it is the largest. Close relatives in the genera Orbea and Huernia also produce stinky flowers designed to attract flies. You can find one or more of them in most garden centers, at least occasionally, or order one on-line from a cactus and succulent nursery.
The giant carrion flower is very easy to grow. Give it full sun or as close to full sun as you can, normal indoor temperatures (it suffers at less than 50ºF [10ºC]), and regular watering during the spring and summer, letting it dry out more thoroughly during the fall and winter. It will enjoy a summer outdoors where it adapts to both full sun and partial shade (it may redden a bit in full sun, but that’s normal for this species). Fertilize only very lightly, from spring to late summer.
Flowering is stimulated by the shortening days of fall. Pollinated blooms will produce a seed capsule that opens to release milkweed-like parachute seeds. Be forewarned that this plant can therefore become invasive in arid climates with mild winters. It has notably escaped culture in Hawaii.
The plant itself is made up of upright spineless, 4-angled, succulent stems about 8–12″ (20–30 cm) tall. You may think it looks something like a cactus, but it’s not a close relative, belonging to the dogbane family (Apocynaceae). Close relatives therefore include hoyas and milkweeds. It spreads slowly but surely though offsets produced all around the mother plant and can be easily multiplied by division and cuttings.
The carrion flower: not exactly a name likely to endear it to just anybody, but then, you’re special, right?