Botanical Name: Euphorbia milii Common Names: Crown of Thorn, Christ plant, Christ's thorn Description: Crown of Thorns is a deciduous, herbaceous, perennial shrub with bright green leaves and greenish flowers. The flowers are enclosed within long-lasting and bright bracts of red or yellow. The plant is loose in form, spiny and irregularly shaped, with thick, black spines and its historic presence in the Middle East led to the belief by some that the stems of this plant had been used in Christ's crown of thorns, hence the common name. In its country of origin (Madagascar) the plant will grow to 5 or 6 feet tall; however, in the United States, it typically grows to 3 feet, or 2 feet when grown as a houseplant.