Someone on Facebook a while back ws looking for an ID for their cactus. I told them that it was probably a Cleistocactus and asked if they'd sell me a cutting. I eventually came across a post somewhere of a similar looking plant described as "Cleistocactus senilis", which I'm not sure is a...

It may also be Ferocactus emoryi subs. rectispinus as the young plants have slightly hooked central spines that straighten as they get larger. Ferocacti can be hard to ID as this size.

Can someone tell me how they die?

Do they just shrivel up or do they start rotting or what?

Interesting to see you people buying premixed soluble fertiliser like that. It seems expensive. I mix up my own. I paid about $70 for a 20kg bag of potassium nitrate a few years back, then I throw in monopotassium phosphate and soluble trace elements, then I boil the whole thing up and use a coffee...

Interesting to see you people buying premixed soluble fertiliser like that. It seems expensive. I mix up my own. I paid about $70 for a 20kg bag of potassium nitrate a few years back, then I throw in monopotassium phosphate and soluble trace elements, then I boil the whole thing up and use a coffee ...

It should be fine to move into full sun if it's been out in part sun for a while.

Yes, that is also a fair possibility. Maybe OP can chime in with where it's grown?

Huh, a google search of Ferocactus pottsii has turned up a cactus that looks exactly like mine, so thank you I believe you're right! Is there any particular characteristic that made you say Ferocactus? I ask because I actually dismissed ferocactus because it doesn't have the spines for it, clearly ...

It's a Ferocactus, except that the spines are unusually small for most Ferocactus species. I believe this is either Ferocactus pottsii or Ferocactus schwarzii. Looks like Ferocactus latispinus (or similar!) to me. It's far too round for F latispinus. They normally grow more half-sphere. The spines a...

Cleistocactus winteri is the modern name.

Looks like sunburn to me. Variegation on cacti is more sensitive to sunburn than other parts of the plant. It's probably stuffed.

E.castanea is another possibility, I agree. but it is hard to say without flowers. Even in the wild they look very similar, I had a chance to see them in habitat a few months ago. Their location and especially morphology of the lower tube help to identify particular species: https://llifle.com/Ency...

Lucy_V wrote: ↑Mon Dec 05, 2022 3:26 pm It is also resembling Eulychnia breviflora

Looking at my plant, I don't think it's E breviflora because of the flowers, but the flowers do look like E castanea to me. Thoughts?

Example: https://chileanendemics.rbge.org.uk/tax ... tanea-phil

I have this plant I grew from seeds but the label faded: https://i.imgur.com/veyV7HT.jpg I thought it said "E... R...", and presumed it was some Echinocereus, but now it has gotten a bit bigger I'm thinking a Ferocactus. I have a F Fordii seedling that's getting to a similar size and thoug...

Pyrethroids (pymethrin, bifenthrin, tau-Fluvalinate etc) will all work as contact insecticide. Some are also systemic and are advertised as being uptaken by leaf.