Questa è ritenuta da molti la più affascinante fra tutte le mammillarie. E in assoluto uno dei cactus più belli.
Scientific name: Mammillaria luethyi,
Origin: Mexico, Northern Coahuila
Habitat: Limestone slabs in Chihuahuan Desert
Description: M. luethyi is a very tiny plant, but by far one of the most spectacular members of its genus, distinctive when not in flower because of the 'spination' (if it can be called that!) at the tips of the tubercles, and even more magnificent in flower. It is solitary or branching in several stems, mostly beneathe the ground.
Cultivation: It is a tiny plant of slow growth, for this reason it is often seen grafted to enhance growth speed, as most of the available stock has so far been propagated this way. Grafted plants grow fast, branch profusely and are very floriferous. But it is relatively easy to cultivate plants on their own roots and no special care required, at least given the same care with drainage and watering that is afforded to other species of Mammillaria with fleshy roots. Needs good drainage and regular water in summer. It should be dried out completely for its winter rest when it will withstand temperatures down to to -4°C for short periods.
The luethyi needs full sun which will help to maintain the lustre of the spines and plants compact. Poorer luminosity levels produce a green anaesthetic plant with open, far and wide spaced areoles.
It is prone to mealy bug and red spider mite.
Propagation: Seeds (rarely available) or by offshoot. Older specimens may branch around the base, so they can be propagated by cuttings in spring, cuttings root relatively well but plants on their own roots are quite slow. Plants are sometimes grafted onto column-shaped cacti, which is a much easier way of propagation than sowing.