Crown Of Thorns Plant, a Complete Indoor Care Guide

A crown of thorns plant will light up your home with its colorful blooms. It likes a dry indoor environment and is not particularly fussy.

Yellow-Orange Crown Of Thorn Plant
crown of thorns
(Image credit: liuyushan)

How To Grow A Crown Of Thorns Plant Indoors

Crown of thorns, also known as Euphorbia milii and Christ thorn plant or Christ plant, is a woody, succulent shrub native to Madagascar. The crown of thorns flower is a popular houseplant in North America, known for its clusters of pretty, colorful blooms and its easy maintenance needs.

In Thailand some people say the number of flowers on a crown of thorns plant foretells the luck of the plant keeper. The plant has been improved over the years and now produces more and larger flowers than ever before. Hybrids of this plant bloom almost year-round.

Quick Facts

Botanical name: Euphorbia milii

Height: 3.0 to 6.0 feet (.90 to 1.8 m)

Spread: 1.5 to 3.0 feet (.50 to .90 m)

Sun exposure: Full sun

Soil requirements: Well drained

Hardiness zones: 9 to 11

When to plant: Spring, any time indoors

Crown of Thorns Plant Care Indoors

Crown of thorns plant care relies on providing this houseplant with adequate sunlight and warmth, and not too much water.


To thrive and produce pretty flowers, a crown of thorns plant needs full sun. Place it by a window with at least four hours of bright, direct sunlight.


Water crown of thorns plants when the soil is dry to a depth of an inch (2.5 cm). In winter, let the soil dry out down to two or three inches (5.0 to 7.5 cm). Water thoroughly, but don't let the plant sit in standing water.

Temperature & Humidity

Crown of thorns is a great houseplant for dry indoor air. It prefers dry conditions and needs good airflow. It can tolerate temperatures down to 50 degrees Fahrenheit (10 Celsius) but does best from 60 to 75 degrees (15 to 24 Celsius)


Potting soil for crown of thorns must drain very well. For the best results, use a soilless mix or a cactus and succulent mix.


Use a general liquid fertilizer every few weeks during the growing season. Dilute the fertilizer by half for winter and apply only every month.

Problems, Pests & Diseases

Crown of thorns may be bothered by mites, scale, mealybugs, and thrips. The primary issue, however, is root rot and fungal diseases caused by overwatering, standing water, or too much humidity or too little airflow.


Grown outdoors, crown of thorns is a small shrub. When grown as a houseplant, you can keep it smaller through careful pruning. Many hybrids grown today were bred to remain small and compact, so you likely do not need to prune often.

Be aware that the sap can irritate the skin, so where gloves and wash tools well after pruning.

Crown of Thorns Propagation


You can successfully keep a crown of thorns in a smaller container to maintain a small size, and it will still produce flowers. Nonetheless, its a good idea to repot every few years to a slightly bigger container.


Only grow crown of thorns outdoors in beds in zones 9 through 11. In colder climates, you can grow plants outdoors in containers and bring them in for winter.

During the dormant season, potted crown of thorns still needs plenty of sunlight but need less watering and fertilizer. They will drop leaves but should revive in spring with more water and feeding.

Best Crown of Thorns Varieties to Grow Indoors

Pink Cadillac. Native crown of thorns are mostly red, but this variety produces bright pink flowers.

Gabriella. This variety is also pink and does particularly well in smaller containers.

Crème Supreme. For a creamy, white variety, try Crème Supreme.

Brush Fire. Brush Fire is a good variety for bright red blooms.

Zephyr. This cultivar has apricot-colored flowers with a unique bell shape.

Frequently Asked Questions

Is Crown of Thorns a Good Houseplant?

Crown of thorns is a fairly easy houseplant to grow if it gets enough sunlight and is not overwatered.

Be aware that it is toxic. The sap is irritating to the skin but also harmful if consumed. Keep these plants out of reach of pets and kids.

Can I Put My Crown of Thorns Outside?

Yes, even if you live in a colder environment, crown of thorns can go outside in summer. Be sure it gets plenty of sun and does not get overwatered or end up in standing water.

Jackie Carroll

Jackie Carroll has written over 500 articles for Gardening Know How on a wide range of topics.