To me this looks like cold. I have sprayed with a disease and bug killer about a month back. I welcome any suggestions?

I was pondering this same thing a few weeks ago too Nick. I believe after the initial Spring growth where watering is fine there follows a mid-summer dormancy period during the hotter spell which may account for the more tap rooted ones beginning to cook. I've had this happen with a couple of more t...

I'd say it is Krainzianus var. Minimus.

My guess would be Mollicula.

Interesting plants Blossfeldia. Is the Geohintonia clay/soil pure gypsum? looks like it would be a bit much for the plant to live in if not. I'm assuming the Aztekium Valdezii you have is ex-habitat?

Peter wrote:
I have to express my dsappointment that none of you experts has been able to guess which is the real cactus.....

It's inside, warm and looking a little Melocactus-ish.

I think its Trichocereus Peruvianus.

Wow, An absolutely amazing looking plant. Any other details or pics Ralph?

Hi Eric. Some years down the line you may have something looking a little similar to this, which may or may not influence your decision to graft. Mainly cristate heads on top of older ones, plus the two newer healthy offsets which have grown reasonably fast over the last few years.

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