u/Aevriel

The largest of the former-greenovias, though ironically one of the only forms which hasn’t yet been botanically recognized. You may also see this plant under the name “Greenovia diplocycla var. gigantea,” however…

1. “Greenovia” were merged into the Aeonium genus decades ago and are considered by most botanical authorities to just be another part of the immense diversity of Aeonium species

and 2) the name was never actually published anywhere, so it isn’t accepted taxonomically. (And personally I think it would be better suited as a subspecies rather than a variety anyways)

‘Giganteum’, like its name suggests, is a gigantic form of Aeonium diplocyclum found in one specific area of the island of La Gomera. If you’ve read Marco Cristini’s Aeonium book, you’d know that he suggests that ‘Giganteum’ is “most likely a hybrid.” This is false, however (and while I think Cristini is an absolute gentleman and appreciate the work he does, if there’s one critique I have it’s that he’s a bit too quick to dismiss unusual wild plants as hybrids). There are no signs of hybridization and, truthfully, it doesn’t make sense considering that ‘Giganteum’ possesses zero traits of any of the other Aeonium species it cohabitates with.

In fact, studies have shown that there are both diploid (two sets of chromosomes) and tetraploid (four sets of chromosomes) forms of Aeonium diplocyclum in the wild, and it is highly likely that ‘Giganteum’ is one of the tetraploids. Tetraploidy is known to cause a form of gigantism in some plants, with there already being precedents in other Aeonium species. Aeonium simsii, for example, also has a larger tetraploid form and smaller diploid form (and also a triploid hybrid form between the two).

I’ve been lucky enough to have someone go locate, observe, and photograph diplocyclum ‘Giganteum’ in habitat for me. The problem with ‘Giganteum’ is that it isn’t entirely isolated from standard diplocyclum in the wild. The further north you go in ‘Giganteum’s’ habitat range, the more the regular diploid form of diplocyclum starts to appear. It makes taxonomic classification messy and difficult. How does one tell the difference between a juvenile diplocyclum ‘Giganteum’ and a mature regular diplocyclum? And what about naturally occurring hybrids between the two? In fact, it’s almost like the wild population of ‘Giganteum’ exist more as a gradient - the largest specimens all appear in one specific area, and the further you move away from that point the smaller the plants seem to become.

Regardless, Aeonium diplocyclum ‘Giganteum’ is a truly stunning plant. I grew mine for six years before it finally bloomed for me. I’ve made a few hybrids of it, and I’m also currently regrowing it from seed produced by my original specimen. There used to be a seed company ran by the botanist who discovered ‘Giganteum’, and I was lucky enough to get my hands on a plant grown from those seeds. However those seeds are no longer offered and most of the specimens I’ve seen labeled as diplocyclum ‘Giganteum’ in cultivation nowadays are branched hybrids (the true plant almost always remains solitary).

Not particularly the most interesting hybrid I’ve created, aside from the sheer size of its inflorescence. SHEESH.

Hybrid is Aeonium diplocyclum x Aeonium castello-paivae ‘Sarae’ (AKA Aeonium castello-paivae var sarae, although it’s never been properly published so that name is not recognized, taxonomically speaking). Created by me 🤭

Shown in a pot 6in (~15cm) across.

This plant originally was a bit of a “blah” plant. It has mostly been a blue-green-grey color up until recently, after I decided to move it into stronger light and those Sarae colors started showing up more.

I wasn’t originally planning on doing anything with this plant but maybe I’ll try a couple of crosses with it now that it’s looking a bit more vibrant. I could do something really funny and cross it with Aeonium glutinosum, which similarly has some outrageously long, slender inflorescences compared to the rest of the plant. Could really lean into that ridiculous inflorescence, plus glutinosum could add some more reddish stripes and unusual leaf shapes to the mix as well.

We’ll see. If anything, I’ll probably just do a small handful of crosses with it. I know it may seem like an unusual plant, but flowers aside (and as someone who has now made hundreds of hybrids) it doesn’t really have that much to offer me that I couldn’t achieve with other more visually interesting hybrids.

Still, sometimes unexpected things can happen - like how this lil dude turned out to be absolutely PACKING lol.

Also known as Aeonium rubrolineatum or Aeonium arboreum var rubrolineatum. All of these are simply different taxonomic placements/names of the same plant - although I do currently have multiple forms of rubrolineatum (but none which have been botanically recognized as being separate).

My rubrolineatum is an older plant, and for some reason has decided to become a bearded lady, with all of these air roots haha. But it is perfectly healthy and thriving. The air roots started forming after I moved the plant from Seattle (where I used to live) to California, so I believe it happened due to the sudden change in climate. But it’s harmless and looks kinda cool!

I’ve made a toooooon of hybrids with this specimen. In fact my first ever xMonanthonium (Aeonium x Monanthes) hybrid was created using rubrolineatum! And I use this plant to try and breed hybrids with distinctive patterns and stripes.

Botanically, rubrolineatum is hardly different from holochrysum. There are multiple forms of rubro in existence, but generally speaking the only differences between rubrolineatum and holochrysum is that rubro tends to be a bit more striped, get a bit more tan, and has flowers which can have small red markings on the undersides and which range from a dark yellow to a pale bronze (as opposed to holochrysum’s bright and purely yellow flowers).

Feeling a bit under the weather so not exactly the best photos I’ve ever taken, but oh well lol.

Zoom in on those stripes and markings on the leaves. Super pretty, no? Especially when combined with the pinkish red base colors.

This is a hybrid I made purely for aesthetic purposes. No botanical mysteries to be solved here, lol. It’s a bit dehydrated and closed up from the heatwave we’ve had where I live, but the weather is cooling down this week and it’s supposed to rain soon so maybe it’ll open back up and give me some more growth before going fully dormant for the summer. Either way, I think I’m going to go ahead and transplant this individual into a larger pot before the rain comes so it has time to establish its root system over summer and before the start of the next growing season. That way, come autumn, it’ll be prepped and ready to put out some serious growth for me right away. Hoping to get a bloom to hybridize this plant further, but it’s already so pretty. I’m always a sucker for stripes!

This is a hybrid of Aeonium saundersii. Anyone else care to guess the second parent? (this is a first generation cross between two species)