Scientific Name: Mammillaria
sempervivi DC.
First description by De Candolle, Mem. Mus. Hist. Nat.
Paris 17: 114 (1828)
Origin:Central and northern Mexico (Hidalgo, San Luis Potosi,
Nuevo Leon, Guanajuato, Queretaro)
Habitat: Grows at altitudes of 1200 to
2.250 m. |
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Description: Solitary at
first, or slowly clumping flat with ground.
Stem: Flattened globose to depressed globose and not rising much
above ground level, dull grey-green 7.5 cm wide (eventually gets to 10
or 15 cm in diameter)
Tubercles arrangement: 13 - 21
Tubercles: Pyramidal, firm.
Axil: Woolly.
Radial spine: Mostly hidden under white wool, usually on young
stems only, 2 - 6, white, bristle-like, to 3 mm long.
Central spine: 2 - 3, very short, stout, reddish brown to black,
becoming grey with age, to 4 mm long.
Roots: Taproots large.
Flowers: Funnelform in a rings on the crown barely rising above
the tubercles, whitish to pale yellow with pinkish midstripe, 1-2 cm
long and diameter. Flowering period spring
Fruit: Club-shaped, red, to 10 mm long.
The var. caput-medusae
and var. tetracantha; often mentioned in literature and sometimes
offered in seed lists, should be fully synonymized with the type
variety.
Cultivation:
This is a popular slow growing
and easy to cultivate cactus species.
Water regularly in summer, but do not overwater (Rot
prone) Use pot with good drainage and a
very porous potting media, keep dry in winter.
Feed with a high
potassium fertilizer in summer.
It is quite frost resistant if kept dry, hardy as low as -5° C
Outside full sun or afternoon shade, inside needs bright light,
and some direct sun.
Easily flowered. Some plants will slowly offset , and clumps can
be produced in time.
Propagation: Direct sow after last frost.
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Cultivation and
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