How to Grow Crown of Thorns

Wikimedia Commons

Crown of Thorns

Euphorbia milii

shrub

Crown of Thorns is a succulent shrub native to Madagascar, featuring thorny stems adorned with vibrant flower-like bracts in red, pink, yellow, or white. The plant produces small true flowers surrounded by showy, colorful modified leaves (bracts) that can bloom year-round in ideal conditions. It's an excellent houseplant and outdoor ornamental in warm climates, valued for its drought tolerance and long flowering period.

Looking for a specific variety?

When should you plant Crown of Thorns in your zone?

Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.

Get my Crown of Thorns timeline →

Example Crown of Thorns timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Crown of Thorns

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Crown of Thorns

    Around Jul 16

    ≈ 90 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Crown of Thorns dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily; tolerates bright indirect light indoors
💧
Water: Water deeply when soil is completely dry; overwatering causes root rot. Reduce watering in winter. As a succulent, it prefers drought to wet conditions.
📏
Spacing: 24 inches
📅
Days to maturity: 90-180 days for flowering from transplant
🌱
Planting depth: Top of root ball level with soil surface; do not bury stems

Soil

Type: Well-draining cactus or succulent potting mix
pH: 6.0-7.0
Amendments:
Perlite or pumice for drainage Coarse sand Avoid heavy organic matter

Growing Zones

Find your zone →

Thrives in zones 10-11; grown indoors elsewhere

10a 10b 11a 11b

Sign up free to see if Crown of Thorns grows in your zone — and get a personalized planting timeline.

Get my Crown of Thorns timeline →

Growth Stages

1

Seedling

4-8 weeks

Tiny plantlets with first true leaves emerging; very delicate and slow-growing

Keep soil barely moist, provide bright indirect light, maintain 70-80°F temperature, protect from direct sun initially

2

Vegetative

3-6 months

Young plant developing thorny stems and glossy green leaves; no flowers yet

Water sparingly, gradually increase light exposure, fertilize monthly with diluted succulent fertilizer, ensure excellent drainage

3

Pre-flowering

2-3 months

Plant matures, stems thicken, leaf production continues, flower buds begin forming at stem tips

Maintain full sun exposure, reduce watering slightly, apply phosphorus-rich fertilizer monthly, prune leggy growth if desired

4

Flowering

Several months to year-round in optimal conditions

Colorful bracts appear in clusters at branch tips; true flowers emerge from center of bracts in yellow or other colors

Continue full sun, water only when dry, fertilize every 2-3 weeks with bloom-promoting formula, remove faded bracts to encourage new flowers

5

Dormancy/Rest

2-3 months (seasonal)

Plant growth slows in winter months; flowering decreases; stems may appear less vigorous

Reduce watering significantly, lower temperature if possible (55-60°F ideal), reduce or stop fertilizing, maintain bright light, prune to shape if needed

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

High-water-need plants Bog plants Ferns Tropical rainforest plants

Common Pests

  • Spray with isopropyl alcohol solution or insecticidal soap; isolate plant; check regularly for reinfestation

  • Increase humidity, spray with water to dislodge, use neem oil or miticide if severe; ensure good air circulation

  • Remove manually with cotton swab dipped in alcohol; spray with horticultural oil in early morning or evening

  • Improve drainage, reduce watering frequency, repot in fresh cactus soil if stems are mushy; trim affected roots

Uses

🍳

Not edible

Culinary

Crown of Thorns is ornamental only and not suitable for consumption due to toxic sap. [source]

🏠

Ornamental houseplant and landscape accent

Household

Crown of Thorns is grown indoors as a long-flowering potted plant and outdoors as a shrubby border or specimen plant in warm climates. Its colorful bracts and year-round blooming make it valued for interior decoration and tropical/Mediterranean garden design. [source]

🏠

Cut flower arrangements

Household

The vibrant bracts and flower clusters last well in vase arrangements when cut from mature plants. Seal cut stems with warm water or cauterize with flame to prevent sap leakage. [source]

💊

Traditional medicine uses

Medicinal

In some cultures, Crown of Thorns has been used traditionally to treat skin conditions and wounds, though scientific evidence is limited and the plant is toxic if ingested. [source]

🦋

Pollinator attractor

Wildlife

The bright flowers attract butterflies and bees, making it beneficial for pollinator-dependent gardens. It provides nectar for various insect species in warm climates. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Crown of Thorns is ornamental; harvest by removing cut flowers or bracts for indoor arrangements. Cut stems cleanly with sharp pruners. Note: Plant sap is mildly toxic and irritating; wear gloves and wash hands after handling. Wear eye protection when cutting due to thorns.

Fun Facts

  • 🌱 Crown of Thorns is native to the arid regions of Madagascar and is named for its resemblance to the crown worn by Christ in Christian tradition.
  • 🌱 The plant can live for decades and become quite woody and tree-like with proper care; some specimens over 20 years old develop thick, sculptural trunks.
  • 🌱 All parts of the plant contain a milky sap that can cause skin irritation and gastrointestinal upset if ingested; wear gloves when handling to avoid contact dermatitis.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Join 30,000 gardeners planning their gardens with LizPlants.

Get your personalized Crown of Thorns planting timeline

Tell us your zip code and we'll calculate exactly when to start Crown of Thorns seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.

Get my Crown of Thorns timeline →