Information about M. sempervivi

Hi all,
my intention is to buy a plant of M.sempervivi like this
from http://www.gargamel-cactus.com/

before purchaise i need to know which are the habits of it: temperature, frost resistance, sun or shade tollerance, blooms etc.
Googling i found that this plant is not frost tollerant (in winter must live indoor), blooms are scentless and it doesn't produce seeds (!!).

Thank you to whom will share his experience.

Hi Alessandra,
M. sempervivi is a plant from central Mexico (states such as Hidalgo) and will not tolerate frost. It does survive OK at 5-6C.
It has yellow flowers, although I believe that some plants with this name have purple flowers. But those might be M. formosa ssp pseudocrucigera, which appears quite similar. The next photo on the website from which your photo comes (#244) is not M. sempervivi but M. formosa ssp. pseudocrucigera.
I am a bit worried about the identification of the plant in your photo. M. sempervivi doesn't usually divide dichotomously as the plant in your photo, but I don't have a better name for it though.
I hope other members can offer an opinion.

Chris43, your help is very appreciated! Thank you.

I would be happy to view the above plant M.sempervivi.
Over the years I have grown many 1000's of plants from seed and I have found that on the odd occassion species that would not normally divide dichotomously have done so very early after germination.
The picture below shows Rog 400, ignota / dixanthocentron which has divided dichotomously.



In the past I have posted a picture of my plant of M.crucigera ssp tlalocii FO-223 which had also divided dichotomously into 4 heads.

The different between crucigera and tlalocii is that tlalocii is supposed be ' solitary stemmed variant '. If it is the case that tlalocii is able to divide dichotomously then this would call into question the validity of mantaining it at subspecies level.

Hi Tam,
thank you for yours very interesting informations.
I know only this about your mammi (see here)

"(..)This is one of the Mammillaria commonly called "Owl Eye Cactus", known for dichotomous branching (forking or dividing into two parts). Although dichotomous branching is not a common occurrence in cacti in general, it happens for some reason in this particular subspecies. What is interesting about this cactus is that it began as a single head, and it has now divided twice, forming what will be four separate branches. When the division process started, it was obvious that four heads would appear, but I don’t think the one head divided quadruply. Most probably, one head became two, and then those two immediately divided. (..)"


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About my M. sempervivi post: the plant is or was at Jardin Botanique Collection de Porrentruy.