This article first appeared in the SDCSS monthly newsletter, and references the local club meeting.
Coryphantha! A genus you may or may not have heard of – they’re native to Mexico and even up into the Southwest US. In recent years, some species have become highly desirable, particularly those that have monstrose characteristics. Coryphantha elephantidens is one that is quite popular for its large, fleshy growth, with an enermis form winning a Judge’s Ribbon at our last summer show!
Personally, I’ve always wanted a big monstrose Coryphantha elephantidens, as I’ve seen some exceptional funky specimens pictured in the collections of online plant friends.
Coryphantha elephantidens v. enermis from Thorn Oasis
At one time, these species were all classified in the Mammillaria genus. Now in their own genus, they have a notable difference: these bloom from their newest growth (first year growth), at the crown of the plant, where Mammillaria bloom lower down, typically in second year growth.
Most Coryphantha will grow as clumps, slowly spreading into clusters of small-bodied cacti. The plant at the center of this article pups readily and is filling its pot at a rate that is very gratifying. For many of us growing show plants or the rarer species, we’re used to a slow growth rate and that plants of a winning size and shape are often a decade or more old. With Coryphantha, you can often cultivate an impressive clump in just a couple years – much more attractive to those of us with short attention spans.
What species is it?
A lot of introduction for what should be a single species – but as I was researching for this article, I discovered that my Coryphantha may not be the species I thought it was.
I first purchased the cactus as part of a wholesale order from a local grower 3 years ago, and fell in love with them after seeing them bloom. I held on to one and have nurtured it since, being rewarded with repeated blooms all through the warm months of the year.
I bought it, and have been selling my occasional pups from that first plant, labeled as Coryphantha andreae.
Googling that species name for this article uncovered that the species name is no longer used – instead, they should be Coryphantha pycnacantha. Looking that up, however, showed a cactus with a very different growth habit than my plant. From there began a spiral down an internet rabbit hole!
If you’ll humor me, I’ll take you along. This was a great experience in looking up sources and trying to determine what is accurate (or not!).
First blooms with the plant I kept – from the top, you almost can’t see the body of the plant!
Coryphantha pycnacantha?
This species has a relatively large range, through Oaxaca, Mexico and up into Pueblo. A synonym for the species is Coryphantha calipensis, at least for this variety, which can also be referred to as Coryphantha pycnacantha var. calipensis.
But as I just said, looking this up…it didn’t seem quite right. I often reference the website llifle.com as a starting point for researching cacti and succulents, and if I’m lucky, there’s substantial information and photos on a species that’s new to me. On llifle, I saw this photo used to show “the typical central spines of an older plant as well as the flower”.
Um.
My cactus’s main plant body looks about the same age, but mine looks like this:
In the Llifle photo, the growth of the tubercules points upright, resembling a pineapple as described on the page. It’s also described as having dimorphic growth: young forms have a “purely radial-spined youth stage with short tubercles, but develops central spines and long tubercules as it ages”.
Those central spines were what threw me off as I was researching. My plant doesn’t have those! Looking closely at the photo, you can see the large central spine sticking out like a reverse rhino or unicorn horn from the tubercules. My plant just has the furry aeroles and curving spines that look like simply larger forms of the smaller plant growth.
Coryphantha elephantidens?
Okay, what other options are there that more closely resemble what I’ve been growing the last few years?
The species Coryphantha elephantidens didn’t seem quite right – when I’d first researched it, the main species shown on llifle has pink flowers and a lumpy appearance.
But then…I discovered the subspecies! And felt a little silly: Llifle describes this as “among the best-known cacti”, which was news to me.
This is what’s shown as Coryphantha elephantides ssp. bumamma
This could almost be a clone of my plant! Lucky me – I have a Coryphantha elephantides, just like I always wanted all along!
Now knowing the probable latin name, I could better look up similar plants, and found far more resembling my own.
This subspecies of elephantidens is native to a smaller area of southwestern Mexico, near Guerrero. Practically speaking, the two species I thought my plant might be have nearly identical care. Coryphantha pycnacantha’s range overlaps and borders the range of Coryphantha elephantidens ssp. bumamma, so this shouldn’t come as much of a surprise. The main difference is where they are typically found; as far as I can find, the pycnacantha is typically in foothills and among gravel, where elephantidens is more common among grassland and scrub.
You might be asking why I limited my sources here just to llifle – if you were to google Coryphantha andrae, you’ll certainly find plenty of other sites that show plants that look similar to mine. When I first looked up care on the plant, I saw something ‘close enough’ on Dave’s Garden, which I’m sure others also reference. In the last year or two, other websites have started to pop up, with better sites regurgitating the same generic information or posting care information that’s dubious at best. I’m even guilty of having photos referencing the wrong latin name on my own website!
Google isn’t automatically a provider of correct information; it’s just providing you the most popular websites or photos that are associated with what you typed in the search bar. If plenty of people are using the wrong name, Google will show you plenty of information related to that incorrect name.
This is one of the biggest challenges as you get into less common species: how do you trust that what you’ve looked up online is accurate or true?
Personally, I try to rely on pages that provide source material, which Llifle’s website does. You can find the books referenced and look up the same information used to provide these plant descriptions! Seeking input from more experienced growers also goes a long way, as they’ll help you examine your plants more closely and better confirm if something is or isn’t what it was originally labeled as.
I’ll note with some humor that the several times I’ve brought my Coryphantha in for judging in the winter and summer shows, I’ve had no comment from the judges on my incorrect name for the plant. I can’t blame them! I can’t say that I’ve seen them shown often, so it’s reasonable to think the judges did the same thing I did: “Sure, that sounds about right, I’ve probably just not seen this species before.”
All of this to conclude: research! Check out books from the club library! And make sure when you research online that you’re checking for (reputable) sources. Be willing to learn that you might be wrong. It’s just a plant, after all. I don’t think my cactus is upset with me for labeling it incorrectly all this time. 😉
I’ll bring my Coryphantha with me to our January meeting for you to take a closer look yourself. I invite others with Corypthantha to bring yours in so we can collectively compare and see how accurate our latin names are. In my research, it sure appears to be that this genus is labeled incorrectly just as often as it’s got the right name – let’s figure ours out!
Growing Coryphantha elephantidens
These are summer growers that rapidly gain size and pup readily when kept warm and provided ideal conditions. Their roots are fibrous, and they’ll appreciate a pot just a little bigger than the body of the cactus. I’ve found terra cotta azalea pots to work very well, choosing pots with a diameter 1 to 2” larger than the cactus itself. They don’t need a particularly deep pot, and do better in the shallow azalea pots as it allows the roots to fill the pot without risking rot at the bottom.
They can be sensitive to overwatering, and if you know you’re a chronic over-waterer, using a highly porous soil is your friend. I have mine potted in 50% pumice and 50% cactus & succulent soil, which allows for rapid drainage and for the roots to dry relatively quickly.
During the hot summer months, they’ll enjoy regular water. With the fleshy body, you can use that to gauge the water needs: it’ll deflate slightly as it gets thirsty, and you just need to give it a good drench in the evening and it’ll plump right back up again. I try not to water mine too intensely from above to preserve the wooly growth, which I love to see.
In spring, when the cacti are first waking up, I’ll give them a dilute feed with a balanced fertilizer once or twice while the days are only in the 70s or 80s. As the daytime highs start to climb, I’ll increase the frequency to every other time I water. I keep my Coryphantha in my greenhouse, where summer highs are 125F quite often, so I water every week to two weeks from June through about mid-September. The rest of the year is as-needed, dropping to nearly none in winter. When it’s below 50 at night, I keep my Coryphanthas of all species dry, same as my other cacti.
To encourage the best growth and wool development, it needs at least some direct sun exposure. I have grown mine both inside and outside my greenhouse, and make sure that no matter where I place it, it’s shaded during the hottest part of the day. It doesn’t need to be full shade! Just dappling from a tree’s foliage, or the shade from the bars of a shelf unit can be enough.
If it helps, try to remember their growth habit in the wild: somewhat hidden under grass, in the shade of larger boulders, or under shrubs. They get lots of light, but they’re also protected from the heat and intensity of midday sun.
Delightfully, these cacti have huge, showy flowers and they’ll give them to you in large clusters and all through the warm months. Mine will start blooming in spring, and I’ll keep seeing flowers all through summer and into early fall.
C. elephantidens ssp. bumamma produces yellow flowers with a hint of pink on the outer petals. I’d describe them as big and showy, but they’re apparently smaller than the main species, which produces large, soft-pink blooms.
C. pallida ssp. calipensis also produces large yellow to white-yellow flowers, although they seem to have less of the reddish pink tint to the outer petals. They have red stamens, and seem to have a redder center to the bloom than the elephantidens does. Having said that, my sample size is small and limited to what’s posted on Llifle, so that could be incorrect!
They seem to be self-fertile, as mine produces fruit several times a year with seed that appears viable (dark and looks similar to seeds I’ve ordered online). It’ll be my first year sowing my own seed, so ask me in spring how my seeds did!
The fruits are greenish hued, and pop out of the wooly crown when ripe. They look like Mammillaria fruit on steroids in terms of size, but the color seems more like the cactus has produced a tumor that’s falling off than an actual ripe fruit.
The wool at the top is extremely attractive to mealybugs, so keep a careful eye on your cacti to be sure the mealybugs aren’t hiding. I grow several wooly cacti, and I’ll check them at least once a month by using a flat acrylic paint brush to “brush” the cacti and check under the wool against the flesh of the plant. This can fluff up the wool to make it look like a little sheep, but you have to be careful not to overdo it! It’s very easy to just brush the wool right off.
Simpler and less pretentious than brushing your cactus is to use a set of dull-tipped tweezers to carefully check under the wool and against the tubercules. Less fun, though.
I prefer to treat mealybugs with a combination of treatments: systemic, to catch the bugs that are surely hiding under the wool and won’t be reached by a spray, and with spray pesticide that specifically mentions mealybugs on the label. I use Bonide pellets sprinkled over the soil on the pot to provide the systemic pesticide, and repeat both the pellets and spray every two weeks for at least 3 treatments.
You may notice in the mealybug photo some yellowing of the flesh of the cactus where I pulled the mealybug from. It can resemble sun-bleaching from getting too much sun, but what you should look for is the yellowing to occur under the wool. That’s a major sign of mealybugs, or some other pest, hiding under the wool and eating at your plant. Where there’s wool, the mealies are less likely to show as the little white powdery things on the stems of the cactus, so by the time you see them it’s often quite an infestation. Check your cactus regularly!
I hope you enjoyed following along with me on the journey of discovering the true latin name for my plant, and embracing how easy they are to grow! This cactus is one of my all time favorites, with funky tubercules, lots of fluffy wool, and giant sunshine-y flowers that’ll bring a smile to your face all summer.
