Mammillaria johnstonii

Scientific Name: Mammillaria johnstonii (Britton & Rose) Orcutt
Synonym: Mammillaria johnstonii var. sancarlensis , Mammillaria johnstonii var. guaymensis , Neomammillaria johnstonii
Family: Cactaceae

Recommended Temperature Zone:
USDA: 10-12

Sun Exposure: Light shade to full sun

Origin: Mexico (coastal Sonora: around Guaymas). Locally abundant in a quite limited area, it is threatened by local development and agriculture.

Growth Habits: Solitary, 6 to 8 inches tall (15-20 cm), up to 6 inches in diameter (15 cm); milky sap; tubercles 0.4 to 0.5 inch tall (10-13 mm), 0.24 to 0.36 inch wide (6-9 mm); axils with white wool; very young areoles with white wool; 2 to 6 purplish-black centrals, 0.4 to 1 inch long (10-25 mm); 10 to 18 radials, 0.24 to 0.4 inch long (6-10 mm)

Propagation: Seeds

Fruits of the Mammillaria johnstonii at the Huntington Gardens in December (HBG 59513)

Blooming Habits:
Light pink flowers with darker midstripe, in April, 0.4 to 0.5 inch long (1-1.2 cm), 0.4 to 0.5 inch in diameter (1-1.2 cm). The fruit is clup-shaped, 1 inch long (2.5 cm).