A Final Six Plants I'm Not Currently Mad At (Po through Z)

And now, the thrilling conclusion of the plants-I'm-not-currently-mad-at series. (A-G is here; H-Pn is here.)


1. Podocarpus macrophyllus

Podocarpus has died several times under my care already, and may again, but we're getting along for the moment. This one's my longest-lived yet. (Two and a half years!)

Date: September 2012.
Pot size: 4.5" / 11.5 cm?
The problem is always watering: let a Podocarpus get too dry, and you will have an unhappy Podocarpus. My solution to this has been to keep mine in a larger pot than I normally would (I repotted shortly after the above photo was taken, in fact), and to water every time its turn comes around in the watering cycle (i.e. every two weeks), whether it feels dry or not.¹

Date: April 2010.
Pot size: 4" / 10 cm.
Otherwise, not that big of a deal. I have a faint recollection of mealybugs or scale in the recent past, but I'm not sure if that's something that actually happened or just something I was dreading really vividly. It's been happy with artificial light so far, and has lived in the basement since its arrival, so the cooler temperature and higher humidity down there may be contributing to its non-death.

In any case, this is a plant that really shouldn't be working out for me, but it nevertheless is. At the moment. We'll see how that goes.


2. Polyscias fruticosa

As nervous as I was about buying Polyscias fruticosa, it's turned out to be a really reliable, good plant. They have a reputation for being temperamental, though this is probably more about them preferring consistency. Don't move it around a lot, and give it dependable water, and it should be fine.

Date: September 2012.
Pot size: 12" / 31 cm.
They're also surprisingly fast growers, when they feel like it. This plant has at least tripled in height in the three and a half years it's lived here. (I'm actually starting to worry that it might outgrow its spot!)

Date: May 2010?
Pot size: 6" / 15 cm.
I've had it in an east window for at least a couple years. It's been getting water every two weeks, plus a generous amount of fertilizer (year-round), but that's going to have to change, since I moved it into a larger pot a month ago. Watering will probably be more like once a month now.

It's never had any pests, and defoliated dramatically only once, this last summer. I think that was because it had gotten pretty rootbound, and was drying out too quickly, though it's also possible that the top leaves had just become so abundant that the leaves at the bottom were getting shaded out. Only the bottom leaves dropped, and not terribly many of them.


3. Rhapis excelsa

Rhapis excelsa is exactly the kind of plant I'm wanting to spotlight with these posts. I all but forget that I have it, because it never does anything terribly dramatic. It doesn't even need watering as often as most of the plants. It doesn't bloom, it grows really slowly, it holds on to its leaves, it suckers sluggishly -- there's really no reason to ever notice it. It even looks pretty much the same now as it did when I first got it:

Date: September 2012.
Pot size: 8" / 20 cm.
Date: March 2008.
Pot size: 6" / 15 cm.
At the same time, though, this is actually what a lot of people are looking for in a houseplant.² And even if it's not six times the size it used to be, there's a lot to be said for a plant that will just mind its own business and grow without getting bugs or requiring pruning or whatever.

The only complaint I have about Rhapis is that the leaf tips used to burn on me. They've stopped, since the plant got relocated to a cooler, darker spot, but it's not clear whether the change in temperature and light fixed the tip-burn problem or if it was something else entirely.³ Presently, it's in the basement, on the floor, where it gets heavily filtered light from some of the shop lights (though it doesn't have its own shop light) and some indirect sun, on the days when we have sun. I water it about every 4 or 6 weeks, and fertilize lightly year-round. I've yet to see any pests on it. I would love, love, love to propagate R. excelsa, but it grows so slowly, and propagation is so uncertain, that I haven't been willing to take the gamble yet.


4. Stapelia gigantea

S. gigantea is another plant like Plectranthus verticillatus, that's gotten smaller since I've had it; in this case, the reduction occurred because I cut off a big chunk of it for cuttings. (If I remember correctly, all the cuttings were successful. They're more wrinkled than the parent, and floppier, which is worrisome, but all are still alive, and most are now producing new growth.)

Date: September 2012.
Pot size: 6" / 15 cm.
The flowers are certainly interesting, though not necessarily the main thing I like about the plant. It scores points with me mostly for its tactile qualities, not so much its appearance (though the appearance is cool) or the flowers' smell (which is in fact unpleasant, though not as terrible as I'd been led to believe it would be). That, and it's easy to grow.

Date: September 2009.
Pot size: 6" / 15 cm.
My plant has been in a west window since I've owned it, not counting a brief period when it first arrived and I had it outside. (A bad idea: it burned.⁴) It would probably prefer a bit more light than that, but that's as good as I can do, and it seems to be able to get by on that. The cuttings are all downstairs under artificial light, which is even less bright than a west window, and they do okay, though it's worth noting that they aren't growing very fast.

The parent plant gets watered every time the watering cycle comes around, every two weeks; the cuttings get water more like every three or four weeks, but it's colder in the basement, and they aren't getting as much light, and they're in plastic pots, so that makes sense. I fertilize year-round. Sources elsewhere on the internet tell me not to let the temperature go below about 50-55F (10-13C), but neither the plant room nor the basement normally get that cold, so temperature and humidity aren't much of an issue. There have never been any pest problems; I've been watching for scale lately (because the cuttings are in that neighborhood of the basement), but so far I haven't seen any.


5. Stenocereus thurberi

Stenocereus thurberi was one of the plants I was offering for sale in the spring this year, because even though I liked the look of it, I didn't seem to have enough light to convince it to grow. Nobody was interested, though, so when I ended the plant-selling, the S. thurberi went outside, and once it was out there, it did produce some new growth.

Date: September 2012.
Pot size: 4" / 10 cm.
It's not dramatic new growth, of course. You would be forgiven for not noticing that the two pictures were different. But the top two or three areoles on each rib above is new growth as of this summer, and I've had the plant for almost three years. So it's a big deal to me.

Date: December 2009.
Pot size: 3" / 7.5 cm (along diagonal).
Other than its unreasonably high demand for light, S. thurberi has been easy enough to grow indoors: I try to keep it drier and reduce fertilizer in the winter, though I still water about every 4-6 weeks.

I suppose it's a little odd to praise a plant for not growing, but that's basically what I'm doing here: I've thrown out cacti that grew while not getting enough light,⁵ because the new growth is small, pale, and weak, and even when given better conditions afterward, plants don't necessarily fill in the spindly growth.⁶ So it's actually good if a plant refuses to grow for three years because it doesn't have enough light. Hopefully it won't keep growing this winter out of some misguided biological momentum or something.


6. Zamia furfuracea (?)

I repotted Z. furfuracea (or whatever it is⁷) in August, because it had been in the same 4-inch (10 cm) clay pot for a few years. It turned out that it did need to be repotted, but it's also lost a few leaves since then, which is something it basically never did before. It's also growing much larger new leaves now, so it's fine: the point is just that after a long period of being a good, stable plant for me, it's starting to undergo some Changes, and we don't yet know for sure how that's going to turn out.

Date: September 2012.
Pot size: 6" / 15 cm.
That said, though, I have no complaints with it so far. It's been fine close to an east window. It used to get watered every two weeks; I think so far I've continued to do that, post-repotting, but it may slow down to every four weeks in the winter, depending on how quickly it seems to be drying out. Neither temperature nor humidity are likely to be an issue to someone growing it indoors, and I've never had pest problems on mine.⁸

Date: October 2009.
Pot size: 4" / 10 cm.

Also relatively non-upsetting:

Sansevieria cylindrica
Sansevieria hargesiana
Scindapsus pictus
Selenicereus chrysocardium
Stenocereus pruinosus
Stromanthe sanguinea 'Triostar'
Tradescantia spathacea
Vriesea imperialis

-

¹ Is it possible to overwater a Podocarpus? Probably. I have one houseplant book that says they're prone to root rot if they're kept too wet or left to stand in water. It's not something I've ever seen personally, though.
² My recollection, from the garden center days, is that the houseplant every customer is looking for:
• has large, shiny, mostly-green leaves, with optional variegation,
• needs almost no light at all,
• produces huge flowers, year-round, in any shade of any color desired,
• is pleasantly- but not overpoweringly-scented,
• never needs fertilizer or repotting,
• is nontoxic to pets and children,
• and will grow to the height of exactly six feet (1.8 m) tall and then stop getting taller.
It takes a few months, but one does eventually get used to disappointing the customers.
³ The old spot was also in the basement, so things like temperature and humidity should have been more or less the same; the main difference between the two situations is that the first location had a shop light directly over the plant. I'm also fertilizing more now, but it would be weird if that was responsible: ordinarily if there's a tip-burn problem on a plant, more fertilizer will make it worse, not better.
⁴ They can, of course, grow outside in the sun: I just didn't try as hard as I could have to acclimate it gradually. It had most likely been growing inside on someone's windowsill before they brought it to the consignment store, so it would have been accustomed to lower light.
⁵ Specifically: Parodia microsperma and Echinocactus grusonii.
⁶ Some do, some don't: I have some mildly etiolated Myrtillocactus geometrizans that grew some weak new growth after arriving here, but they spent the summer outside this year and managed to fill in somewhat. They still don't look quite right: the newest growth is disproportionately big compared to the growth that immediately preceded it --

-- but the stems also thickened up a little bit, enough so that I'm optimistic that the plants will even themselves out eventually.
⁷ I'm positive that it's a Zamia; I just don't know which one.
⁸ I know they can get scale, though: when I worked at the garden center, we threw out a batch of Zamias (not necessarily the same species as mine) because they developed a bad scale infestation. Which was depressing: up to that point, I had been considering buying one of them for myself.

Cactus Blindness: Its Causes and Treatment

It's time to admit my shameful secret: I have cactus blindness.

Cactus blindness is one of a number of widespread horticultural learning deficiencies (HLD), resembling (and often overlapping with) other HLDs like fern blindness, shrub blindness (I am also considerably shrub-blind, by the way), and palm blindness. Afflicted individuals are easily able to learn and recall names of different cactus species, but are unable to visually distinguish cacti well enough to apply the names accurately to plant specimens.

Ferocactus latispinus? Not particularly confident, but I didn't see much that was particularly close. Flat, yellow, curved spines don't happen a lot. UPDATE: There appears to be consensus that this is in fact Ferocactus latispinus.
Many causes have been proposed for HLDs, ranging from the socioeconomic (lack of exposure to, or accurate identification of, enough plant species in childhood) to the organic (HLDs sometimes occur following stroke or brain injury in previously unaffected individuals). Though below-average intelligence and sensory impairment may also lead to the inability to distinguish cactus species from one another, persons with these conditions are specifically excluded from the DSM-IV definition of cactus blindness, as they lead to much broader difficulties.

Cactus blindness is also distinct from the condition called cactus alexia: in the latter, species are easily distinguished, but the patient experiences great difficulty in learning the names that go with the plants.

I originally suspected this of being a Pachycereus pringlei, and then for some reason decided that it couldn't be, so I switched to Carnegiea gigantea. Carnegiea is fairly common in cultivation (easy to grow from seed), but it's also incredibly slow-growing, which means that it should cost more than these did. So now I'm leaning back toward Pachycereus pringlei. UPDATE: Could go either way, but the smart money appears to be on Carnegiea gigantea.
I bring this up first of all because of Karen715's brave admission a couple weeks ago that she, too, suffers from cactus blindness. Her courage has given me the strength to admit that I, too, find it extremely difficult to identify many of the specimens I encounter. (It is my hope that we can start a support group or something.)

Stenocereus thurberi. Not particularly certain about this, but it does match: newest spines are dark and become lighter, plus the dark areoles -- if it isn't Stenocactus thurberi, it's something that's fairly indistinguishable from it. Also I kind of want this now. UPDATE: Does in fact appear to be Stenocereus thurberi. Yay me.
Secondly, I recently went back to my former workplace and photographed a few cacti there (bought a couple, too, alas), thinking I could identify them easily and then use the photos for yearbook pictures, and I think I even actually did, with great difficulty and the assistance of the photos at cactiguide.com, identify a couple of them. However, some of them continued to stump me, either because none of the 1257 species represented at cactiguide.com looked like the plant in question, or because far too many of them did for me to be able to pick one. (Some of the more questionable photos I took are decorating this post; I welcome any ID verifications or suggestions anybody wants to throw at me.)

Pachycereus marginatus. I'm just, you know, damn positive that I've got a P. marginatus this time. I had previously reported buying a P. marginatus, which for some reason I really really wanted, but I now think that that plant is probably an Isolatocereus dumortieri instead. So now I have this, which I really think probably is a Pachycereus marginatus. UPDATE: Experts agree.
Treatment of cactus blindness typically falls into one of three types. In conventional cactus blindness therapy (CCBT), CB sufferers are encouraged, with the aid of worksheets, photographs, and (when possible) actual cactus specimens, to describe plants in minute detail, with the aim of training the individual to notice the small distinctions between species. This is essentially the training of afflicted individuals to become cactus taxonomists, and while it has a high success rate (about 80% of subjects will become able to identify at least 100 cactus species with at least 70% accuracy), it also takes a considerable amount of time, and requires the assistance of a qualified trainer at all times. Consequently, it is very expensive, and CCBT-certified trainers may not be found in all areas, though cases are known of people who have taught themselves to overcome cactus blindness through informal CCBT-like methods.

Was tagged as "Lemaireocerous." They probably meant Lemaireocereus, though that still doesn't help, since the genus is now obsolete, and the species in it were distributed across five or six other genera. None of the pictures within those genera at cactiguide.com resemble this as far as I'm concerned, and of course we have no real guarantee that Lemaireocereus was the right ID to begin with. UPDATE: I lean toward the suggestion of Browningia hertlingiana (see comments).
The other treatment approach is known as wholistic cactus blindness therapy, or WCBT. WCBT de-emphasizes verbalization of the distinctions between species and instead focuses its efforts on the subconscious: subjects are presented, repeatedly, with randomized pairs of photos or specimens of cacti, and asked to identify whether they are the same species or different species. This, it is said, trains the mind to identify the relevant details which distinguish one species from another, without the tedious completion of worksheets as in CCBT. WCBT is also easily adapted to computer software, making it considerably more affordable and accessible than other therapies. Critics of WCBT point out that it does little to link the image of a particular cactus species to a species name, and is therefore not particularly useful in fostering cactus-related communication. Many WCBT trainers have responded to this charge by adding an additional four-week program to the end of a course of WCBT specifically for the purpose of linking names to the now-mentally-distinct species in the subject's mind.

NOID cactus #2. Lots of stuff looks sort of like this, but the arrangement of the spines (short ones pointing up, left, and right, plus a long one pointing down) seems like it's trying very hard to mean something. I couldn't find a match, and wasted a really ridiculous amount of time trying. UPDATE: I kind of lean toward Mammillaria winterae, though to be safe I think I'll just go with "Mammillaria sp."
Incremental cactus blindness therapy (ICBT), the newest of the CB therapies to gain acceptance, focuses on learning the distinguishing characteristics of only the most commonly-sold or -observed cacti, and those with the most distinctive appearances (e.g. Astrophytum myriostigma, which is fairly hard to confuse with anything else), slowly expanding the pool of one's knowledge only once the initial easy group have been mastered. Its largest advantage over the other methods is that it is more immediately useful than either CCBT or WCBT, enabling the subject to identify several commonly-encountered cactus species after the very first therapeutic session. ICBT is also somewhat adaptable to computer software and requires considerably less of a therapist than CCBT, making it less expensive and easily available. The main disadvantage of ICBT is that accidental exposure to unknown cactus species can result in the mental assignment of mistaken identities, which are frequently difficult to unlearn later on. ICBT also has a rather steep learning curve, which subjects often find discouraging, leading to a dropout rate more than double that of CCBT or WCBT.

To the best of my knowledge, the above therapies have not been attempted with other varieties of HLDs.

NOID cactus #1. This one makes me kind of crazy: I see it for sale all the time, so you'd think it would be easy to find out what it is, but no. I found plenty of approximate visual matches at cactiguide.com, but nothing I could be positive about. UPDATE: Appears to be Parodia leninghausii.
Personally, I'm working a combination of CCBT and ICBT, on my own, with only the internet to guide me, and if I manage to learn anything I'll let you know. Meanwhile, perhaps we should be looking for some available church basements, or setting up a dedicated CB blog, or something. Who's in?

Mammillaria spinosissima. I'm actually pretty confident about this ID; the coloration is pretty distinctive, and I know it's a fairly popular species ("red-headed Irishman cactus"). (UPDATE: Experts agree.) This is one of the two I went ahead and purchased.

UPDATE: Enormous thanks to Daiv Freeman, Peter Breslin, erin, and CelticRose, for their help and suggestions on the NOIDs in this post, and confirmations on the ones I thought I had right.
-

Totally skippable political correctness disclaimer and commentary:

I'm not trying to imply that actual learning disabilities aren't real or shouldn't be taken seriously. They of course are, and should. The targets of ridicule here are more the non-disabled people who patronizingly claim every little obstacle's defeat as being inspiring and courageous than for the people who actually have the disabilities, people who try to make unchosen conditions into something shameful, and my own very real difficulty in distinguishing cacti from one another.

Sometimes overcoming disability / adversity / tragedy actually is courageous, of course, but sometimes one never really gets a choice about whether or not to overcome, and in any case it's kind of a weird thing to take someone who has an unusual life situation and single them out as being even more unusual by waxing poetic about their courage and whatever.

As far as it goes, I also don't mean to suggest that the blind are more disabled than others, by using the word "blindness" as part of the term for my made-up condition. It seemed like a better metaphor than, say, deafness, because people generally look at cacti a lot more than they listen to them.

As I have alluded to before, I don't want PATSP to be accidentally offensive to anybody, of whatever age, gender identity, sexual orientation, degree of disability, country of origin or residence, race, mental illness, etc. I want as much of the offensiveness as possible to be on purpose. At the same time, pretty much any reference to certain of these topics is going to be offensive to somebody, however it's phrased, because minority communities don't ever necessarily agree unanimously on PC language, reclaiming slurs, etc. (There's not even total agreement on whether "the disabled" exist as a group, or, if they do, exactly who belongs in it.) So I figure my choices are to never mention these people at all, effectively "disappearing" minority groups into nonexistence, or mention and try to make clear that I'm doing the best I can not to piss people off through my own privilege as a white, able-bodied, cisgendered, American male. (I've been noticing lately that I tend to assume my readers are U.S. or Canadian residents, in a way which probably marginalizes readers from other countries, and have been trying to think of ways to make that happen less often.) I do actually try to think about these things. Sometimes I don't think hard enough.

If I have expressed myself in a particularly inelegant or ignorant way on the matter, please let me know.