Mammillaria vetula subsp. gracilis

Mammillaria vetula subsp. gracilis

Synonym: Mammillaria gracilis
Family: Cactaceae
Common Name: thimble cactus
Origin: Mammillaria vetula subsp. gracilis originates from the states of Hidalgo and Querétaro, eastern Mexico.
Description: The thimble cactus is a small species that forms a cluster of slender, cylindrical stems, each covered with stiff white spines. These spines radiate like a star, giving the plant a lacy appearance. Eventually, clusters will develop into large rounded aggregations. From spring to early autumn, creamy-white bell shaped flowers may form, possessing pinkish-brown midstripes.

Interesting Features:
- M. vetula subsp. gracilis stores water in raised tubercles, which will expand upon irrigation. Flowers will emerge from the axils of these tubercles, raised from the previous year’s growth, to create an interesting visual effect.
- The stems of this cactus are very easily knocked off, but readily develop roots.
Uses: The thimble cactus is popular in cultivation and can be used in rockeries, desert/xeriscape gardens, and as a houseplant.

Cultivation and Care:

Watering: Low
- M. vetula subsp. gracilis is extremely drought tolerant and requires only sparse irrigation during the summer. Do not water in winter, and never allow to stand in prolonged moisture, as this can lead to root rot.
Soil: Plant in a well-draining cactus or succulent soil with mineral grit (coarse sand, pumice, or perlite), and maintain a pH between 6.1 and 7.8.
Lighting: Provide 2-6 hours of direct sunlight each day and partial shade for the remainder. M. vetula subsp. gracilis can be grown in moderate shade, but should be introduced slowly to sunlight, to avoid severely scorching the cacti.
Propagation: The thimble cactus readily forms offsets from the top and sides of stems, which easily develop roots when removed. Additional methods of propagation include through seed (sown after the last frost), and woody stem cuttings (during spring or summer).
Cold Tolerance: 20°F, USDA hardiness zones 9a to 11.
Special Accommodations: M. vetula subsp. gracilis is difficult to kill and hardy against light frost, requiring few extra accommodations. However, growth will benefit from occasional fertilization in summer, and irregular repotting during the growing season. Repair any damaged tissue with fungicide, and wear gloves when handling to avoid damage by the numerous spines.

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