Other cactus flowers mid-May to early June 2025

In addition to the Echinopsis hybrids I showed you in my last post, the following cacti also flowered in the last few weeks:

1. Acanthocalycium spiniflorum
2. Astrophytum asterias
3. Astrophytum capricorne
4. Astrophytum myriostigma
5. Astrophytum ornatum
6. Chamaecereus hybrids
7. Echinocactus horizonthalonius
8. Echinocereus dasyacanthus
9. Echinocereus dasyacanthus var. ctenoides
10. Echinocereus pentalophus
11. Echinocereus poselgeri
12. Echinocereus reichenbachii
13. Echinocereus rigidissimus var. rubrispinus
14. Echinocereus schmollii
15. Echinocereus viereckii var. morricalii
16. Echinocereus × lloydii ‘Persimmon Orange’
17. Homalocephala texensis
18. Lobivia acanthoplegma var. roseiflora
19. Lobivia hybrid
20. Parodia elegans
21. Parodia mammulosa
22. Parodia mammulosa var. roseolutea
23. Parodia muller-melchersii ssp. guiterrezii
24. Tephrocactus alexanderi

Grab something to drink because this post is long!

Acanthocalycium spiniflorum

I bought this small cactus at the Ruth Bancroft Garden many years ago and have never seen it for sale since then. Most of the year it doesn’t stand out, but when it flowers, it’s a showstopper. Mine has already produced two waves of flowers this year, and I expect another wave or two.

Acanthocalycium spiniflorum

Astrophytum asterias

Last year I made a foray into the rabbit hole that is Astrophytum asterias. There’s a variety of different forms, often with unique markings. I’d been warned that they rot easily in the winter because they have a small and weak root system, and I did lose a few. Still not sure why. But here’s a Super Kabuto V type that made it and flowered recently. The flower color on Astrophytum asterias varies, ranging from creamy white to yellow and even red.

Astrophytum asterias, Super Kabuto V type

Astrophytum capricorne

Capricorne means goat’s horn in Latin, ostensibly in reference to the curved spines. This species is quite variable. The first one below almost has a cage of spines; the second one is a form with thick black spines called ‘Buffalo’ (or ‘Taiho-Gyoku’ in Japanese).

Astrophytum capricorne #1

Astrophytum capricorne #1

Astrophytum capricorne #2

Astrophytum capricorne #2

Astrophytum myriostigma

Like virtually all Astrophytum species, myriostigma can be quite variable. The form below is called ‘Kikko Nudum’. According to the Encyclopedia of Cactus, “This rare Japanese cultivar is unmistakable for its pointed tubercles along the ribs edges, in fact its areoles stick out with large notches between them, giving them a saw tooth look. The furrows which appear transversely on the ribs cuts the continuity of the ribs and the plants appear decorated with a geometrical design which is raised above the surface. When viewed from above these plants resemble a tortoise-shell.”

Astrophytum myriostigma ‘Kikko Nudum’

Astrophytum ornatum

This Astrophytum ornatum is the largest astrophytum I have. It’s planted in the ground next to the front door, and it sailed through last winter with flying colors. I love the vivid markings – and the dense cluster of flowers it produces. It’s already bloomed twice this year.

Astrophytum ornatum

Chamaecereus hybrids

These tiny beauties are commonly called peanut cactus. There’s a huge number of Chamaecereus hybrids out there. I have two, and both of them have been flowering nonstop for weeks.

‘Hot Flame’ with 15+ flowers

‘Hot Flame’ with my thumb nail for scale

‘Sunkissed’ has tiny flowers. On the right, you see how many heads there already are in this clump.

Echinocactus horizonthalonius

This Southwestern native has several common names, including devilshead, turk’s head, and eagle’s claw. I have two specimens, and both have dense spination. The magenta flowers are pretty but nothing special. But that doesn’t matter because it’s a beautiful cactus year round.

Echinocactus horizonthalonius

Echinocereus dasyacanthus

Echinocereus dasyacanthus is known as the Texas rainbow cactus because of its colorful spines. It’s my favorite echinocereus species, not only because of the spines but because of the flowers. They’re large for the genus, have rich yellow petals (or even white-and-yellow bicolor) that contrast beautifully with the green stigma lobes, and last longer than any other cactus I have – over a week. Compare that to echinopsis flowers which often barely make it through one day!

Echinocereus dasyacanthus

Echinocereus dasyacanthus

Echinocereus dasyacanthus

Echinocereus dasyacanthus

Echinocereus dasyacanthus

Echinocereus dasyacanthus var. ctenoides

I don’t really know how Echinocereus dasyacanthus var. ctenoides differs from the species. The spines are a little less dense, and it flowers at a very small size. But other than that, it’s just as pretty as its (big) sibling.

Echinocereus dasyacanthus var. ctenoides

Echinocereus pentalophus

This is the kind of cactus nobody pays much attention to for most of the year. In the wild, the stems crawl on the ground because they’re too weak to stay upright (see here). But come May, they burst into flower and are impossible to ignore. The typical flower color is magenta (see here). I have the rare white-flowering form. (The magenta flowers in the photo below are from Echinocereus viereckii var. morricalli.)

Echinocereus pentalophus (white flowers) and Echinocereus viereckii var. morricalli

Echinocereus pentalophus

Echinocereus pentalophus

Echinocereus pentalophus

Echinocereus pentalophus

Echinocereus poselgeri

Echinocereus poselgeri, like E. schmollii further down, used to be in the genus Wilcoxia, but Wilcoxia has been subsumed into Echinocereus. E. poselgeri, aka the dahlia cactus, has slender stems that barely manage to keep themselves upright. In habitat, it typically relies on woody vegetation for support. As unassuming as E. poselgeri looks, its flowers are spectacular.

Echinocereus poselgeri

Echinocereus poselgeri

Echinocereus poselgeri

Echinocereus reichenbachii

Echinocereus reichenbachii has large flowers, among the largest in the genus. Unfortunately, unlike other Echinocereus species, they only stay open for a day. E. dasyacanthus flowers, for example, last up to a week. Still, I’m not mad when they’re this showy.

Echinocereus reichenbachii

Echinocereus reichenbachii

Echinocereus reichenbachii

Echinocereus rigidissimus var. rubrispinus

Like Echinocereus dasyacanthus, E. rigidissimus goes by the common name rainbow cactus because of its colorful spines. I have three of them planted along the sidewalk, and when they’re in flower, passers-by regularly stop to look.

Echinocereus rigidissimus var. rubrispinus

Echinocereus rigidissimus var. rubrispinus

Echinocereus rigidissimus var. rubrispinus

Echinocereus schmollii

Echinocereus schmollii (formerly Wilcoxia schmollii) has thin stems that are even weaker than E. poselgeri. Mine lives in a hanging planter and seems to be quite happy there, judging from the many flowers it produced this year.

Echinocereus schmollii

Echinocereus schmollii

Echinocereus viereckii var. morricalii

Echinocereus viereckii var. morricalli is the short-spined form of the species. Its stems look a lot like pickles with prickles (sorry, I couldn’t help myself).

My plant shares a large metal bowl with the white-flowering form of Echinocereus pentalophus and an Echinocereus triglochidiatus, which I will soon move elsewhere.

Echinocereus viereckii var. morricalli (purple), with white-flowering Echinocereus pentalophus

Echinocereus viereckii var. morricalli

Echinocereus × lloydii ‘Persimmon Orange’

Echinocereus × lloydii is a naturally occurring hybrid between E. coccineus and E. dasyacanthus, as is Echinocereus × roetteri. Some people swear these hybrids are different, others say they’re the same. Irrespective of that, seedlings of both E. × lloydii and E. × roetteri often have unusual flower colors, ranging from pinks to oranges and even bicolors. My friend Justin and I have batches of seedlings going, but they aren’t of flowering size yet. The selection in the photo below, ‘Persimmon Orange’, came from Kelly Grummons’ nursery, Cold Hardy Cacti.

Echinocereus ×lloydii ‘Persimmon Orange’

Homalocephala texensis

I love the common name of this squat cactus, Texas horse crippler, presumably named thusly because its rigid spines can cause serious injury to horses that step on it. It’s only a few inches tall by up to a foot across and easily hides in the grass. I love the pink flowers with vivid red throats. This cactus used to be in the genus Echinocactus, but has recently been moved to Homalocephala.

Echinocactus texensis

Lobivia acanthoplegma var. roseiflora

This is the only species lobivia I have. The flowers are small, but they have the signature white throat that is often passed on to hybrids.

Lobivia acanthoplegma var. roseiflora

Lobivia hybrid

This is a lobivia hybrid that came to me without a name. It’s a compact plant that flowers freely and often.

Unnamed Lobivia hybrid

Parodia elegans

General note: Parodia and Notocactus are essentially the same genus of cactus, with Parodia being the preferred name because it was used first. Notocactus was formerly a distinct genus, but was later combined with Parodia. Some botanists have argued that there are distinct morphological differences between the two, but Parodia is the current scientific name encompassing both. An easy way to tell them apart: The stigma lobes on what used to be Notocactus are red, while on Parodia they are yellow. At least that’s what somebody once told me.

Parodia elegans may be a small species, but it becomes a mighty giant when it’s in full bloom.

Parodia elegans

Parodia mammulosa

My favorite yellow-flowering parodia (sorry, Parodia elegans). Look at the photos below and you’ll see why.

Parodia mammulosa

Parodia mammulosa

Parodia mammulosa

Parodia mammulosa var. roseolutea

Essentially a pink-flowering variety of Parodia mammulosa above. At least that’s what the experts say. It’s one of the larger parodias and also one of the prettiest. Mine had almost two dozen buds earlier in May and I was hoping they’d open at the same time. Unfortunately, that didn’t happen. Still, this is such a cheery cactus that I can’t complain.

Parodia mammulosa var. roseolutea

Parodia mammulosa var. roseolutea

Parodia mammulosa var. roseolutea

Parodia mueller-melchersii ssp. gutierrezii

The name of this cactus is a mouthful, but it’s a sight to see when it’s in bloom. Mine had so many flowers open at the same time that the body was all but hidden under them.

Parodia mueller-melchersii ssp. gutierrezii (pink-flowering, bottom), with Parodia elegans on top and Parodia werdermanniana on the left

Parodia mueller-melchersii ssp. gutierrezii

Tephrocactus alexanderi

This is the cactus often referred to as Tephrocactus geometricus. I’m going by what the Huntington says: “One of the most awarded specimens in southern California cactus and succulent shows is a magnificent pan full of this globular-jointed opuntioid looking like a heap of gray golf balls. It is shown by Greg and Anna Cavanaugh under the name Tephrocactus geometricus, considered by some to be a synonym of T. alexanderi, a NW Argentine cactus species. It differs in having fewer spines, or none at all, making this such a popular plant.”

I have two specimens, one with 19 “balls” and pink flowers, and a smaller one with four balls and white flowers.

Tephrocactus alexanderi

Tephrocactus alexanderi

Thelocactus rinconensis

Thelocactus rinconensis is highly variable. I have three now, and I selected each one for its long spines. The flowers are pretty generic as far as cactus flowers go, but the total package is nice. (Thelocactus rinconensis is sometimes called the bird’s nest cactus, but so are various other cacti. Proof that it’s best to use botanical names to avoid confusion.)

Thelocactus rinconensis

Whew, when I started this post, I didn’t know there was that much territory to cover!

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