Oreocereus trollii
Native range: High altitudes of the Andes in Bolivia and Argentina
Known names: Old Man of the Andes, Woolly Torch Cactus
Hardiness: USDA Zone 8 (10-20°F) to 11, protect from prolonged frost and freezing temperatures.
Mature Size: 1'-3' tall, 2"-4" wide (slow grower, typically adding 1"-2" per year)
Light: Half day direct sun, full sun
Water: Allow soil to dry completely between waterings; drought tolerant.
Soil: Extremely well-draining, gritty cactus and succulent mix.
Dormancy Period: Winter
Pet-Safe: No
Plant Size: Grown in 2.5" pot, shipped bare root.
 
Slow-growing and columnar, Oreocereus trollii forms an upright stem densely covered in long, white, hair-like bristles and sharp yellow spines that resemble a shaggy white coat. It produces tubular bright pink to reddish flowers near the top of the stems, typically blooming in late spring to summer. In cultivation, it requires a site with bright direct sunlight and an extremely well-draining, gritty succulent soil. People usually grow this plant as a container specimen or in arid rock gardens, as it tolerates extended drought once established. Its species name trollii honors the German botanist Wilhelm Troll, while the dense woolen hair acts as a natural protection against intense high-altitude UV radiation and freezing alpine temperatures.