Home/Plants/Crown of Thorns

Crown of Thorns

Euphorbia milii

houseplant

verifiedReviewed by the GreenScout Team

Crown of Thorns is a succulent shrub native to Madagascar, prized for its vibrant flowers and dramatic spiny stems. It thrives indoors as a low-maintenance houseplant that blooms prolifically with proper light and care. The plant is toxic and should be kept away from children and pets.

Common Problems

Select the problem your Crown of Thorns is experiencing to get a treatment guide.

warning

Yellow Leaveschevron_right

compost

Root Rotchevron_right

trending_down

Wiltingchevron_right

south_west

Dropping Leaveschevron_right

shower

Overwateringchevron_right

Care Guide

light_mode

Light

Bright, direct sunlight for 6+ hours daily; flowering is enhanced by maximum light exposure.

water_drop

Water

Water when top 1–2 inches of soil are dry; reduce watering in winter. Allow soil to dry between waterings to prevent root rot.

compost

Soil

Well-draining cactus or succulent potting mix; add perlite if using regular potting soil.

science

Fertiliser

Feed monthly during growing season (spring/summer) with balanced or flowering plant fertilizer; reduce in fall/winter.

thermometer

Temperature

Prefers 65–75°F (18–24°C); avoid temperatures below 50°F (10°C).

humidity_percentage

Humidity

Low to moderate humidity is acceptable; avoid excessive moisture around foliage.

Toxicity

dangerousToxic to CatsdangerousToxic to DogsdangerousToxic to Children

All parts contain toxic sap that can cause skin irritation and gastrointestinal upset if ingested. Wear gloves when handling.

Common Diseases

filter_dramaRoot Rotchevron_right

Common Pests

coronavirusMealybugschevron_right pest_controlSpider Miteschevron_right hiveScale Insectschevron_right

Seasonal Care

local_floristspring

Resume regular watering and feeding as growth picks up.

light_modesummer

Peak growing season. Water and feed regularly.

ecoautumn

Reduce watering as growth slows. Stop heavy feeding.

ac_unitwinter

Minimal watering and feeding. Protect from frost if needed.

Frequently Asked Questions

Why isn't my Crown of Thorns flowering as much as it used to?

Flowering is directly tied to light — it needs as much bright, direct sun as you can give it. If blooms have slowed, the most common cause is the plant not getting enough hours of strong light.

Is the sap from Crown of Thorns actually dangerous?

Yes — like other Euphorbias, its milky sap is toxic and can cause skin and eye irritation on contact, plus gastrointestinal upset if ingested, so always wear gloves when pruning or handling it.