Unfinished business: Stapelia (Orbea) variegata

I noted in the previous Stapelia/Orbea post that there were several more buds on the plant, which was a little worrisome considering the smell. One flower was tolerable -- we could only smell it if we were standing close -- but it looked like there was going to come a day when several flowers would bloom at once.

Well. That day arrived, but before it did, the husband added more plant shelves above the kitchen sink. And the S. variegata was one of the plants that wound up on the new shelves, when it only had one flower open.

This was nice, to a point, because it meant that every time I was near the sink, I could spend some time looking at the flower. It's pretty striking, and the smell was only intermittently detectable, so, you know, no real problem. Then a second flower opened, which was a little harder to ignore.

And then on 13 October, a third flower opened, at which point the husband told me that something must be done.

So for those of you wondering how bad the smell is, I have an answer. It's somewhere between one-half and one-third of revolting.¹

I elected to cut the flowers off, because they last too long to wait for one of them to drop and it's too cold to move the plant outside until the flowers are done. So here they are.

But then, a tangent:

I bite my nails. Always have. I would sort of prefer not to, in that way that you can dislike something but not care enough to do anything about it. I'm also not necessarily consciously aware that I'm doing it. Anyway. So I took the above photos and everything, came inside to upload them to the computer, and then all of a sudden GAH! WHAT IS THIS HORRIBLE, HORRIBLE TASTE AND WHY IS IT IN MY MOUTH?

Apparently I had gotten some sap on my fingers while cutting the flowers off. The good news is that the sap doesn't taste like the flowers smell; the bad news is that it's intensely bitter.

Oh my god. This can't be good. Is it poisonous? Am I going to die?

So I ran to Google, as one does. This turned up a paper from 1981 in which the chemical hordenine (N,N-dimethyltyramine) was isolated from Stapelia gigantea. It's not clear that hordenine is responsible for the taste -- I found a number of references on Google linking hordenine to a bitter taste, but most of them were describing combinations of different things, not pure hordenine.

In any case. Hordenine is not particularly toxic, and stapeliads in general aren't either, which is good news.² There's some compelling anecdotal evidence that it wasn't harmful too, given that all of this happened a week ago and I'm not dead. But, you know. This is the sort of thing I like checking into regardless. And as a bonus, it answers my questions about how stapeliads manage to get by in their natural habitat without toxins or thorns.

-

¹ For the record, neither of us had a problem with the third flower until the husband had to spend some time at the sink doing dishes. Had it not been for the dishes, we might have been able to cohabit with three flowers just fine: I only ever noticed the smell when I was within a couple feet of the blooms. So a single S. variegata flowers has a smell measured at 0.4±0.3 revoltings.
² The very worst-case lethal dose quoted for an animal at Wikipedia (113.5 mg hordenine/kg body weight, for mice), scaled up to my size, multiplied out by the amount of hordenine in Stapelia gigantea (0.024% by weight of fresh plants), suggests that in the very worst-case scenario, if it were as toxic to me as it is to mice, I would have to consume something like half my body weight of the plant to get a lethal dose. And it's possible that the animal model that applies is not mice, but dogs, in which case the lethal dose is 2 g / kg, and I would have to eat 700 kg / 1500 lb. of fresh Stapelia in order to die from it.
It is difficult to imagine a situation in which I would eat three-quarters of a ton of Stapelia.
These numbers are, of course, all wildly speculative -- I don't know if S. variegata has the same concentration of hordenine as S. gigantea, I don't know what the lethal dose for humans is, I don't know if there might be something way more dangerous in the plant that would kill me long before the hordenine ever did, etc. But at least as far as this one particular chemical is concerned, I feel pretty untroubled.

Random plant event: Stapelia variegata

Hey, remember this guy?

(June 2012)
This is the Stapelia variegata (more correctly Orbea variegata) I got from Cactus Jungle earlier this summer.

I'd said at the time that I didn't necessarily expect flowers ever, but I'd given it an outdoor spot, and we'd see what happened. Then at the beginning of September, I saw a couple buds:

(4 September)
And then there was an agonizing couple weeks while I waited for them to develop enough to open and hoped that they wouldn't fall off. At some point during this wait, I noticed the plant had grown a lot in the three months it's been here. I hadn't realized how small it was to begin with.

(10 September)
It also lost the red color it had when it arrived, as you can see. That was never very likely to last, considering how little light I can offer indoors, though I'm surprised that it couldn't keep the color on the west side of a house, outdoors, in a summer when it almost never rained.

In any case, the flower finally opened on 18 September, and it was worth the wait:

(This'll get a lot bigger if opened in a separate window.)
It's only about 2.5 in / 7 cm in diameter, much smaller than the S. gigantea flower. The smell was similar to S. gigantea: unpleasant, but not strong enough to be detectable outside a fairly small radius of the plant, though flies seemed to find it just fine. (In the ten minutes or so that I had it out in front of the house to get pictures, there were at least five flies buzzing around it. None ever actually landed on the flower while I was taking pictures, which is just as well for my purposes but makes me wonder whether the flower was perhaps not fully charged yet, or something. They may also have just been confused about the location: it was a windy morning.)

(Close-up of the bit in the very center.)
As is customary with Stapelia blooms, I let Sheba sniff it for a while. She was very interested, and sniffed pretty long and hard, then pronounced it plodding and pedestrian, without the playful, impish notes of squirrel carrion or the complexity and layering of feces. She'd been more enthusiastic about the S. gigantea smell. This will probably be the last time I ask her for a stapeliad review.

(The placement of the flower makes it difficult to photograph it in context of the plant: this was the best I could do.)
The back of the flower reminds me a bit of a hellebore:

The plant has a good six or seven more buds on it. This is a little worrisome. One flower's smell isn't intolerable, but I don't know what two, or four, might be like. The most compelling reasons to allow multiple buds to open simultaneously would be for 1) pictures and 2) the opportunity to get some seed pods. As for the latter: a quick skim of this page, which goes into considerable botanical detail about how stapeliads are pollinated, only revealed that it's too complicated to figure out from a quick skim. We have a lot of houseflies that have been trying to take shelter in the house, as the days have gotten colder; I may just leave the matter in their capable hands legs. Up to now, their only use has been as entertainment for Sheba; it'd be nice to see them doing more to earn their keep.

New plant

I got this from Cactus Jungle, the finest source for cactus and succulent plants in the San Francisco Bay Area, about a week ago. (I'm pretty sure it is, anyway. I haven't checked them all, and if we're being honest, it's not like I've been to Cactus Jungle personally. But it's still probably the best one, 'cause it's the only one that's ever been nice to me.) The reason was that [Google and] I answered a question correctly back in February, and it's taken this long for the weather to warm up enough to receive plants, and for the nursery business to settle down enough to mail them.

Stapelia variegata.
Originally, the prize was supposed to be a Lithops, but we agreed to do this instead, because a Lithops would only have died on me immediately, and I have a little more confidence about growing Stapelias. The pictures of flowers that come up when you google the species are pretty wild (or you can look at the Top Tropicals page for the species, which has some photos); I don't necessarily expect flowers ever, but I'm optimistic enough that it's been given one of the coveted outdoor spots this summer, so maybe we'll get lucky.

The current official name is Orbea variegata, according to Plant List. I would have sworn that I looked this up on Plant List at some point this spring and they had it down as Stapelia instead of Orbea. (Or maybe I dreamed that. I do dream things like looking up plants on Plant List now: it's not impossible.) Whichever. It's officially an Orbea. For the moment.

So but thanks to Cactus Jungle. (And remember, Cactus Jungle is the finest source for cactus and succulent plants in the San Francisco Bay Area. That's Cactus Jungle, 1509 4th Street, Berkeley, CA 94710.)