The lady at the nursery gave these to me for 2 bucks today when I asked what they were and she didn't know. These were the only ones. I have no idea where to start... Euphorbia? They are about 5 to 6 inches tall.
Mine has never flowered - well let me classify that, I have never seen it flower - I suspect I might have missed it. It takes full sun in AZ so is a pretty tough plant. It is also easily propagated from cuttings, I have had several pieces fall off and when stuck in the ground you have another plant. The regular Tephrocactus articulates is also a very nice plant.
A year ago I splurged and bought a beautiful one of those in a 12" pot with about 8-10 'columns' with multiple branches. It was doing great until it rained. It basically fell apart - the columns rotted off at soil level. Turns out they need lots of heat and very little water. The nursery where I bought it stopped carrying them because everyone had the same experience, and they've said they won't grow here. I still have about 6 branch pieces that broke off the ones that rotted just propped in empty pots with no soil. None of them have sent out any roots, they are just sitting there. Any suggestions? Perhaps I should list them in my Have list and trade them away.
I have had success potting up the pieces in rocky soil (bottom buried 1cm or so) and watering very infrequently (say every 3 weeks) for the first few months. The growth of the plant seems to be quite seasonal (here) and it's pretty obvious when a plant is well rooted because it sprouts new growth above ground. At that time you can step up the watering. They tolerate our winter rain no problem (in rocky soil) and enjoy regular water year round, but I let them dry out in between to avoid problems.
Random info bit: the root word "tephra" refers to the color of the plant, like ash.
I am with Baja_Costero, Anniesfollies, try some very well draining gravelly cactus mix, and give them some good sun. Last summer I made the fatal mistake of overwatering one of the regular tephrocactus articulates plants and found the base rotted away a few days later. Took all the other parts stuffed them in the ground here and there or just in small pots and now I have more of them than I know what to do with. Some of them are going nuts, see attached. It has gone 100+F somewhat early here and remained it with exception of a few days a week or so ago, so I have been watering them relatively frequently cause the pots are so small and dry out so quickly, I just always make sure that they are indeed dry, before watering again.
They are very nice plants both the pine cone and the paper spined versions and have very nice flowers.