Oreocereus trollii – Old Man of the Andes

Oreocereus trollii, commonly called the Old Man of the Andes, is a columnar cactus native to high-altitude regions of the Andes in Bolivia and northern Argentina, typically found between 3,000 and 4,000 m above sea level. It grows in rocky, well-drained soils where it is exposed to intense sunlight, cold nights, and strong winds.

The plant forms upright columns up to 2 m tall, covered with dense, long, white hairs that protect it from ultraviolet radiation and temperature extremes. Beneath the hair, the stems are blue-green with well-defined ribs lined with clusters of stout, yellow to reddish spines. The woolly covering also helps reduce moisture loss in the harsh alpine climate.

In summer, mature plants produce tubular, reddish-pink flowers near the top of the stems, which are pollinated by hummingbirds. The flowers are followed by small, fleshy fruits containing numerous black seeds. Its slow growth and protective hair covering make it a distinctive ornamental cactus for cooler, sunny climates.

Care Tips:

• Light: Full sun is essential for dense hair growth and healthy development.
• Water: Water sparingly in the growing season when soil is completely dry; keep almost dry in winter.
• Humidity: Prefers low humidity and good air circulation.
• Media: Use a sharply draining cactus mix with added coarse sand or grit.
• Fertiliser: Apply a low-nitrogen cactus fertiliser monthly in the growing season.
• Temperature: Tolerates light frost when kept dry; best grown between 10–27 °C.
• Repotting: Repot infrequently, as it grows slowly and dislikes root disturbance.