The Crown of Thorns

The Crown of Thorns (Euphorbia milii) is a hardy, eye-catching succulent native to Madagascar that has found a home in arid and semi-arid gardens worldwide, including the Mojave and Colorado Deserts. Its thick, spiny stems help it store water and deter browsing animals, while sparse, bright green leaves may be dropped during dry spells to conserve moisture. Small, understated flowers are surrounded by vivid red, pink, yellow, or white bracts that can brighten landscapes nearly year-round. With a slow-growing habit reaching about 3–6 feet tall (smaller in containers), it thrives in sandy, well-draining soil and needs only infrequent, deep watering. Often prized for its Christian symbolism—reminiscent of the crown worn by Jesus—the Crown of Thorns also serves as a heat-loving, drought-tolerant addition to xeriscapes. However, its milky sap is mildly toxic and can irritate skin or eyes, so it’s wise to handle it carefully and plant it away from children’s or pets’ play areas. Although not native to North America’s deserts, it can be an attractive, water-wise choice for gardens as long as it’s properly contained to protect local ecosystems.