Mammillaria luethyi

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.
Growth Habits: Solitary or clustering.
Stem: 1.5 cm in diameter.
Spines: Short, soft and white, not prickly.
Origin: Mexico (Northern Coahuila: limestone slabs in Chihuahuan Desert)
Flowers: Large, rich magenta with a white throat.
Lighting: The luethyi needs full sun!!! Poorer luminosity levels produce a green anaesthetic plant with open, far and wide spaced areoles
Watering Needs: Water sparingly, needs good drainage
Cultivation: The plant is often seen grafted, as most of the available stock has so far been propagated this way. Grafted plants grow fast and are very floriferous.
But it is relatively easy to cultivate plants on their own roots and no special care required.
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Cuttings root very well but plants on their own roots are quite slow.

Mammillaria parkinsonii

Body: Plants solitary at first, later branching dichotomously. Stems depressed globose to cylindrical, blue-green, to 15 cm (5.9 in) high, 10 - 15 cm (3.9 - 5.9 in) in diameter.

Radial spine: 30 or more, fine, white, slightly curved, 4 - 6 mm (0.2 in) long.

Central spine: 2 - 5, usually curved slightly downwards, stiff, whitish with dark tips, upper ones 6 - 8 mm (0.2 - 0.3 in) long, lower ones to 38 mm (1.5 in) long.

Flower: Pale yellow with red midveins, 12 - 15 mm (0.5 - 0.6 in) long and in diameter.

Seed: Brown.Flowering period in Cultivation (Europe):

Frost Tolerance: Hardy to at least 25°F (-4°C)

Minimum Avg. Temperature: 50°F (10°C)

Sun Exposure: Light shade

Origin: Queretaro, Mexico.

Comments: One of the species with the capability of forming very large clumps. In order to keep the clumps tightly formed, high light levels and steady growth are needed; otherwise there is the danger of having a number of elongated heads that are somewhat separated from one another. This species is especially variable in spine length.

Synonymes: M. auriareolis M. cadereytensis M. dietrichiae M. neocrucigera M. parkinsonii var dietrichiae M. rosensis