Scientific Name
Mammillaria microhelia Werderm.
Synonym(s)
Krainzia microhelia, Leptocladia microhelia, Leptocladodia microhelia, Mammillaria droegeana, Neomammillaria microhelia
Scientific Classification
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Subtribe: Cactinae
Genus: Mammillaria
Etymology
The specific epithet "microhelia" (pronounced "my-kro-HEE-lee-uh") means "tiny sun" and refers to the arrangement of the radial spines of this species, which resemble the rays of the sun.
Origin
Mammillaria microhelia is endemic to Mexico.
Description
Mammillaria microhelia is a beautiful, small cactus with cylindrical, green stems that have conical tubercles, each topped with a dense cluster of spines. It can grow solitary or in clumps, and the stems can reach up to 10 inches (25 cm) in height and 2.4 inches (6 cm) in diameter. Each areole bears 1 to 4 needle-like central spines and 30 to 50 slightly backward curved radial spines. The radial spines are white to yellowish, measuring up to 0.2 inches (0.5 cm) long, while the central spines are reddish-brown to almost black, measuring up to 0.4 inches (1 cm) long.
The flowers can reach a diameter of 0.6 inches (1.5 cm) and range in color from pale yellow to pink. They appear in spring, forming a ring around the top of stems.
Hardiness
USDA hardiness zones 9b to 11b: from 25°F (-3.9°C) to 50°F (10°C).
How to Grow and Care
To encourage better flowering, allow the plants to enjoy a cooling period in the winter and suspend watering. Unlike many other cacti, which use their ribs as storage devices, Mammillaria feature raised tubercles, from which spines emerge. When you water, the tubercles will expand for increased water storage. The flowers appear from the axils of these tubercles on the previous year's growth, which accounts for their interesting halo effect. The cactus mustn't be exposed to prolonged dampness and sitting water. Never let your cactus sit in a dish of water. Lastly, ensure to fertilize during the growing season for the best results.
Repot as needed, preferably during the warm season. To repot Mammillaria, ensure the soil is dry before repotting, then gently remove the pot. Knock away the old soil from the roots, removing any rotted or dead roots. Treat any cuts with a fungicide. Place the plant in its new pot and backfill it with potting soil, spreading the roots out as you repot. Leave the plant dry for a week or so, then begin to water lightly to reduce the risk of root rot.
See more at How to Grow and Care for Mammillaria.
Links
- Back to genus Mammillaria
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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