Crown of thorns care guide
Euphorbia milii
Also known as: Christ plant
Pets and children
Considered toxic
The stems carry sharp thorns, and the milky sap from a wound irritates skin and eyes; eating it can inflame the mouth and cause vomiting or diarrhea, so keep it out of reach and consult a veterinarian or doctor if swallowed.
How often to water Crown of thorns
- Spring–Summer (Mar–Sep)
- Every 5 days
- A summer grower that keeps blooming in warm weather: water thoroughly once the topsoil dries, as a guide.
- Autumn (Oct–Nov)
- Every 7 days
- As it cools the soil dries more slowly, so wait a day or two after it dries, as a guide.
- Winter (Dec–Feb)
- Every 14 days
- Indoors, water sparingly a few days after the soil dries; if it keeps flowering in a warm room, a little more is usually fine.
Light and placement for Crown of thorns
It loves sun, and generally the more light the more flowers: outdoors in the sun from spring to fall and at a sunny window in winter, as a guide; low light means fewer blooms and leggy stems.
Overwintering Crown of thorns
Overwintering guide: 5°C (41°F) or above
Tender, with about 5°C as the floor: move it to a bright window indoors when nights fall below 10°C and water less; it may drop leaves in winter but generally leafs out again in spring.
Fertilizing and repotting Crown of thorns
Fertilizer
From April to October, slow-release fertilizer every two months or diluted liquid feed about every two weeks, as a guide; none in winter, and too much gives leaves instead of flowers.
When to repot
Spring–Summer (Mar–Sep)
Common problems with Crown of thorns
- Too little sun stops flowering and leaves only lanky stems.
- Left outdoors in winter, it drops its leaves and dies of cold.
- Water left in the saucer rots the roots.
Tips for growing Crown of thorns
- Cut back overlong stems in spring for more side shoots and more flowers.
- Wear gloves for pruning, because of the thorns and the sap.
- It shrugs off summer heat, so a sunny balcony suits it well.
These are AI-generated general guidelines. They vary with the variety, the placement and the pot size. For effects on pets or children, consult a veterinarian or a doctor.
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