Eulychnia castanea Phil.
Cereus castaneus, Philippicereus castaneus
Eulychnia castanea is a shrubby cactus with green cylindrical stems, ascending at first, later spreading or decumbent, and branching at the base. The stems grow up to 6.5 feet (2 m) long and 4 inches (10 cm) in diameter. The spines are yellow to brown, straight, strong, unequal, and up to 0.8 inches (2 cm) long. Flowers are diurnal, white, up to 2 inches (5 cm) in diameter, and appear laterally near the tip of the stems in summer.
USDA hardiness zones 10a to 11b: from 30 °F (−1.1 °C) to 50 °F (+10 °C).
How to Grow and Care
Eulychnia is not common in cultivation, and only collectors with a specific interest in the genus seem to grow them. It requires full sun or light shade to keep the plant compact with strong colored spines. It tends to bronze in intense light, encouraging flowering and heavy spine production. The light shadow may be useful on the hottest summer days.
These cacti require light but regular watering in summer. Let the soil dry between waterings. Then keep the soil dry in winter.
Eulychnias need to be kept in a cool place during winter rest. They are resistant to light frost if kept on the dry side before and during cold weather. Eulychnias are hardy to 28 °F (-2 °C) in short periods.
Eulychnia likes a very coarse, mineral cactus soil mix but can become too elongated if the soil is too rich. Feed with a high potassium fertilizer in summer.
Learn more at How to Grow and Care for Eulychnia.
This species is native to Chile, along the coastline from Los Molles north to Talinay, Coquimbo.
Forms and Cultivars
- Back to genus Eulychnia
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