Crown of Thorns, Christ Plant, Christ Thorn (Euphorbia millii) Native to Madagascar it is suspected that the species was introduced to the Middle East in ancient times, and legend associates it with the crown of thorns worn by Christ.
Crown of Thorns Crown of thorns has long been a favorite houseplant because it bears abundant flowers without much attention. It will be happiest in a bright spot with indirect sunlight. Keep roots moist (but not wet) and let the surface soil dry out before watering again. With enough light, the 3-foot stems can bear tiny red flowers almost all year long.