Cylindropuntia imbricata
Synonym: Opuntia imbricata
Family: Cactaceae​
​Common Name: tree cholla
Origin: Cylindropuntia imbricata originates from the arid regions of Northern Mexico and the Southwestern United States, primarily occurring in Texas, New Mexico, Arizona, and Nevada. The cacti tolerates a wide range of habitats, including sandy deserts, arid planes, and mountains up to 2,400 meters in elevation.
Description: C. imbricata is a tree-like cactus that develops many candelabra-like branches from a wooden trunk. The cylindrical segments are dark green, forming long spines with papery, detachable sheaths, and glochids that emerge from woolen areoles. From late spring to early summer, showy, bowl-shaped flowers will bloom, purple to magenta in color, with yellow stigma. Flowers will be followed by orange, egg-shaped, and persistent fruits.
  • Interesting Features:
    • The cylindrical joints of C. imbricata are difficult to detach, but will droop during the colder winter months.
    • Additionally, the joints are plagiotropic, and grow in a star-like pattern, creating an interesting form.
    • When grown in cold conditions, the green stems will develop a purple tint.
  • Uses: Tree cholla has been valued extensively for its culinary, medicinal and ceremonial use.
    • The fruits, pits, and segments were consumed by the Acoma, Apache, Keres, Laguna Pueblo, Tohono O'odham, Pima, and Tewa people.
    • The Keres tribe utilized the dried stems for candles, spines for sewing needles, and used the cactus to treat earache, boils, and give strength during war.
    • Additionally, the Indigenous Zuni and Roman-Catholic Penitentes of New Mexico valued C. imbricata in religious ceremonies.

Cultivation and Care:
  • Watering: Low
    • C. imbricata should be watered regularly during the summer growing season, completely allowing the soil to dry in between waterings.
    • In winter, cease irrigation, and do not water on overcast, humid, or cold days.
  • Soil: Plant the tree cholla in sandy, loamy, or gravelly cactus soil, and maintain a pH between 6.0 and 7.5. Poor substratum is tolerated, as long as soil is well-draining. 
  • Lighting: Tree cholla requires full sun exposure and will not be able to grow in shade. Indoor plants should be supplemented with a grow-lamp if bright light and direct sun are not available.
    • For outdoor plants, however, partial afternoon shade can be provided during hot conditions.
  • Propagation: Cylindropuntia imbricata can be propagated from woody stem or softwood cuttings, layering, division, offsets, seeds, and from fruit, which can be planted directly. The simplest method is by removing the stem segments, which will readily root when dried.
    • Developing roots or seedlings should be planted in a neutral soil pH and not watered until new cacti have begun to develop.
  • Cold Tolerance: -30°F, USDA hardiness zones 4a to 11.
  • Special Accommodations: C. imbricata is a very hardy cactus that tolerates both frost and summer heat, but should not be exposed to humidity when grown in cold conditions.
    • Additionally, the tree cholla is one of the most dangerous species of cacti, and should never be handled without very thick gloves. Be cautious when planting, and do not site near walkways or areas frequented by animals.

Sources:
  1. Llifle Encyclopedia of Cacti
  2. The American Southwest
  3. Native American Ethnobotany Database
  4. Plants for a Future
  5. Garden
  6. Plant Lust
  7. Dave’s Garden
  8. World of Succulents