Small Plant Makes a Big Stink!

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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.

The flower is big and, on a sunny day, pretty stinky! Photo: http://www.onsseeds.com

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. 

Fly visiting a giant carrion flower. Photo: Ton Rulkens, flickr

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

Orbea variegata is a close relative with similarly smelly flowers. Photo: worldofsucculents.com

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 is vaguely cactuslike and is sometimes sold under the name “star cactus”. Photo: sg.carousell.com

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?

50 Houseplants That Don’t Mind Dry Air

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Most houseplants just don’t do well in desert-dry air! Source: pexels.com

Dry air is a major problem for houseplants in the winter… and indeed, any indoor plant (seedlings, cuttings, etc.). When the atmospheric humidity is less than 40%, certainly common enough in many homes, plants try hard to compensate by transpiring more heavily, that is, by releasing water to the air through their stomata (breathing pores). The drier the air, the more they transpire, and that can lead to their tissues losing water more rapidly than their roots can replace it. This can result in all sorts of symptoms of stress: wilting, flower buds turning brown, leaves curling under, brown leaf tips, even the death of the plant.

And if that weren’t enough, leaves stressed by dry air are also more subject to pest damage (red spider mites, whiteflies, thrips, etc.)

Some Plants Can Cope

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Plants with thick, waxy leaves cope better with dry air than those with thin ones. Source: davisla.wordpress.com.

That said, many plants, especially those native to arid climates or ones where they are exposed to long periods of drought, have developed ways of compensating for dry air. Cacti and succulents are usually very resistant to dry air and so are some epiphytic plants, like hoyas.

Some plants resist dry air by producing leaves with fewer stomata than normal, thus reducing water loss. Many have abandoned leaves altogether and breathe through their green stems (many cacti, for example). Others keep their stomata closed during the day, when the sun is hottest and water loss is greatest, breathing only a night. (This is called Crassulacean acid metabolism or CAM.) In other words, they essentially hold their breath 12 hours a day! Also, plants resistant to dry air often have extra-thick leaves or leaves coated with wax, powder or hair, all of which reduce evaporation.

Plants That Don’t Mind Dry Air

What follows are a few houseplants that don’t really mind it if the air in your home is on the dry side. Not that they will suffer if you increase the humidity to levels more acceptable to plants in general (most plants prefer a relative humidity of 50% or above) and that indeed is good for your health too, but if improving the atmospheric humidity something you just can’t do, at least these plants will pull through without a complaint!

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Aeonium arboreum ‘Atropurpureum’: one example of a plant that tolerates dry air. Source, Bernard Dupont, Wikimedia Commons

  1. Aeonium spp. (tree houseleek)
  2. Agave spp. (century plant)
  3. Aglaonema spp. (Chinese evergreen)
  4. Aloe spp. (aloe)
  5. Ananas comosus (pineapple plant)
  6. Aspidistra elatior (cast iron plant)
  7. Beaucarnea recurvata (ponytail palm)
  8. Cephalocereus senilis (old man cactus)
  9. Cereus peruvianus (Peruvian apple cactus)
  10. Ceropegia woodii (rosary vine)
  11. Clivia miniata (clivia)
  12. Crassula ovata (jade plant)
  13. Crassula spp. (crassula)
  14. Cryptanthus spp. (earth star)

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    The thick leaves of the dieffenbachia can generally cope quite well with drier air, but you can see just a bit of damage at the tip of this one. Source: Forest & Kim Starr, Wikimedia Commons

  15. Dieffenbachia spp. (dumbcane)
  16. Echeveria spp. (echeveria)
  17. Echinocactus grusonii (golden ball cactus)
  18. Epipremnum aureum (pothos, devil’s ivy)
  19. × Epicactus (orchid cactus)
  20. Euphorbia lactea (candelabra spurge)
  21. Euphorbia milii (crown of thorns)
  22. Euphorbia tirucalli (pencil cactus)
  23. Ficus elastica (rubber tree)
  24. Ficus lyrata (fiddle leaf fig)
  25. Gasteria spp. (ox tongue)
  26. Gymnocalycium mihanovichii friedrichii ‘Hibotan’ (red ball cactus)
  27. Haworthia spp. (zebra plant)
  28. Hippeastrum cvs (amaryllis)
  29. Hoya carnosa (wax plant)
  30. Kalanchoe (kalanchoe, panda plant)
  31. Ledebouria socialis (silver squill)

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    Few plants tolerate dry air as well as living stones (Lithops). Source: Dysmorodrepanis, Wikimedia Commons

  32. Lithops spp. (living stone)
  33. Mammillaria spp. (pincushion cactus)
  34. Opuntia spp. (bunny ears)
  35. Pachypodium lamerei (Madagascar palm)
  36. Pelargonium graveolens (rose-scented geranium)
  37. Pelargonium × hortorum (zonal pelargonium, zonal geranium)
  38. Peperomia obtusifolia, P. clusiifolia (baby rubber plant)
  39. Philodendron hederaceum oxycardium (heartleaf philodendron)
  40. Rhipsalis spp. (mistletoe cactus)
  41. Sansevieria trifasciata (snake plant)
  42. Schlumbergera (Christmas cactus)
  43. Sedum spp. (sedum, donkey’s tail)

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    The nearly round leaves of Senecio rowleyanus are designed to reduce evapotranspiration. Source: Forest & Kim Starr, flickr

  44. Senecio rowleyanus (string-of-pearls)
  45. Senecio serpens (blue chalksticks)
  46. Stapelia spp. (carrion flower)
  47. Streltizia reginae (bird of paradise)
  48. Syngonium spp. (arrowhead vine)
  49. Yucca elephantipes (spineless yucca)
  50. Zamioculcas zamiifolia (zeezee plant)20171227A pexels.com