PlantFun
Plant Needs
Sunlight
Full sun for optimal flower production; tolerates partial shade in hot, arid regions
Watering
Water deeply when the top 5 cm of soil is dry; avoid overwatering to prevent root rot
Temperature
Thrives in 15–25°C; tolerates short periods of light frost down to -5°C
Characteristics
- Leaf: Large oblong leaves with sharp marginal spines; white marbled veins, milky sap released when broken
- Flower: Purple spherical composite heads 5–15 cm wide, surrounded by rigid spiny bracts
- Stem: Erect, branched stems covered in fine hairs and small spiny projections
Care Guide
Watering
Keep soil consistently moist during active growth periods
Fertilization
Diluted balanced liquid feed every 2 weeks. Discontinue fertilization in late autumn when growth slows
Eggshell powder top dressing：Crush dried eggshells into fine powder; sprinkle 1 tsp per plant around the base and water in to release calcium graduallyPruning
- Deadhead spent flower heads to prevent unwanted self-seeding in garden settings
- Remove yellowing lower leaves to improve airflow and reduce fungal disease risk
- Cut back entire plant to ground level after flowering to encourage regrowth in biennial specimens
Toxicity
Warning: this plant may be toxic.
Pets & Humans
Pets: ASPCA: Non-toxic to cats; no reported adverse effects from ingestion or contact
Humans: No known toxic effects; seeds are used in medicinal supplements for liver support
Garden Uses & Culture
Culture: Associated with the Virgin Mary in Christian folklore; symbolizes protection and restorative health
Usage: Medicinal (seeds used for liver support); ornamental garden plant; nectar source for bees and butterflies
