A Crown of Thorns plant, Euphorbia milii, or Christ Plant, is a bushy, slow growing, succulent plant native to Madagascar. According to legend, a Crown of Thorns plant got its nickname after it was associated with the Crown of Thorns worn by JesuOutdoors, in areas where the temperature stays above 55°F (12.8°C), this plant is a tall, woody, flowering bush with stems covered in sharp spines. It can sometimes reach a height of 5-6ft (1.5m-1.8m). A Crown of Thorns plant is one of the most popular types of indoor euphorbias, second only to the poinsettia.
Crown of Thorns Plant Description
As a houseplant, a Crown of Thorns plant can reach a height of 3ft (.9m) and a width of 2ft.(.6m). Like the outdoor variety, these plants have clusters of bright green, tear shaped leaves. The fleshy, dark brown stems are covered in sharp 1/2” thorns and a sticky substance that gets on your hands when you touch the plant. Like a poinsettia, the most beautiful part of a Crown of Thorns plant is the bright, colorful bracts that surround very small flowers. The bracts can be red, yellow, or pink and appear at the ends of 2” stalks. The more intense the light, the longer and more often a Crown of Thorns plant blooms.
Quick Care Tips for a Crown of Thorns Plant
Taking care of this plant is quite simple if you remember a few things:
Provide as much light as possible, but no direct sun.
Water less during the winter when the plant is not actively growing.
A Crown of Thorns plant likes warm in temperatures above 55°F (12.8°C)
Repot every few years in the spring.
Propagate using stem cuttings in the spring and summer
Quick Care Tips for A Crown ofThorns Plant
The unique and unusual looking Crown of Thorns plant is quite a conversation piece. It is an undemanding plant that thrives in very bright areas of your home and loves to spend the summer outside in a shady spot. However, it is a poisonous plant, and the milky, white sap is toxic to cats, dogs, and humans. Read more about common houseplants that are poisonous in Don’t Feed Me to Your Cat: A Guide to Poisonous Houseplants.
A Crown of Thorns plant needs as much bright, indirect light as you can provide,. Avoid placing the plant in direct sun which can damage the leaves.
During the late spring and into early fall, water a Crown of Thorns plant when the top 50% of the soil has dried out. Reduce the amount of water during the winter when a Crown of Thorns plant is not producing new leaves and flowers. Never allow the soil to totally dry out, or a Crown of Thorns plant may develop severe root damage.
Feed a Crown of Thorn plant monthly when it is actively growing with a water-soluble fertilizer diluted to ½ the recommended strength. Use a plant food low in nitrogen and high in phosphorous to limit leaf growth and encourage blooms on a Crown of Thorns plant.
A Crown of Thorns plant likes to be warm and does well in temperatures between 55° F (12.8C) – 95°F (35°C). A Crown of Thorns plant may lose leaves if the temperature goes below 55°F (12.8°C).
A Crown of Thorns plant is a succulent plant that stores water, so average to low household humidity is sufficient.
In the early spring through late summer, a Crown of Thorns plant produces colorful bracts in red, yellow, and pink surrounding tiny flowers. Under the right conditions, a Crown of Thorns plant will bloom all year.
A Crown of Thorns plant is very pest resistant. Mealy bugs and aphids are the main plant pests to keep an eye out for. You can read howto identify and treat these pests in the Glossary of the website.
Plant mildew and fungus are two plant diseases that can develop if the soil of a Crown of Thorns plant is kept too moist or if the humidity is too high. Plant diseases often occur if the room is cool and the light inadequate; so always provide good air circulation and warm temperatures for a Crown of Thorns plant.
A Crown of Thorns plant grows well in a sandy, quick draining soil that is 2/3 cactus mix or succulent plant soil and 1/3 perlite or coarse sand. The soil needs to drain quickly to prevent root-rot.
A Crown of Thorns plant should be reputed every 2-3 years during the spring. Move the plant to the next sized pot only and nothing larger.
Prune and shape a Crown of Thorns plant after it has finished blooming. Wear gloves and a long sleeved shirt to protect your skin from the poisonous plant sap.
Propagate a Crown of Thorns plant in the spring and early summer using 3”- 4” stem tip cuttings. Again, wear gloves to protect your hands from the sap that flows from cuts on the stem. Dip the Crown of Thorns stem tip cuttings in cold water and spray the trimmed areas on the mother plant with cold water to stop the oozing milky sap. Allow Crown of Thorns plant cuttings to dry out for a few days and form a callus on the cut end before planting them.
Poisonous Plant Info
A Crown of Thorns is a poisonous houseplant with a level #2 toxicity. Broken or damaged leaves and stems ooze a milky latex substance that may cause blistering and pain if it gets on any open cuts. A Crown of Thorns plant is very toxic to small children, cats, dogs , and other pets. If consumed, it causes severe mouth irritation, gastro- intestinal problems, and even hemorrhages can occur.
The stems of a Crown of Thorns plant get mushy and the leaves turn yellow and fall off when the soil of the plant is too wet. Move your plant to a warm, bright location with good air circulation. Allow the top 50% of the soil to dry out before you water again.
If you want to propagate a Crown of Thorns plant use stem tip cuttings that are about 3”-4” in length. This is a succulent houseplant so be sure to allow the ends of the stem tip cuttings to dry out for a few days and form a callus on the ends before planting them.
A Crown of Thorn plant needs as much bright, indirect light as possible in order to flower. Using a plant food low in nitrogen and high in phosphorous encourages a Crown of Thorns plant to produce more flowers than leaves.
The best way to prune a Crown of Thorns plant is to cut back a lateral branch to the height you want the plant to be. Wherever you prune, spray the cut with cold water to stop the latex sap from flowing. You can use 3 or 4 inches of the stem tip cuttings to start a new plant.