PlantFun
Plant Needs
Sunlight
Full sun to partial sun; thrives in open, disturbed areas with unobstructed sunlight
Watering
Drought-tolerant; water only when top 5–10 cm of soil is completely dry to avoid root rot
Temperature
Prefers warm temperate to subtropical conditions; sensitive to frost, with above-ground growth dying back at temperatures below 5°C
Characteristics
- Leaf: Alternate, heart-shaped to ovate leaves with coarse toothed margins and rough, hairy surfaces
- Flower: Inconspicuous greenish male and female flower heads; female heads develop into rigid, spiny seed burs
- Stem: Erect, densely hairy stems with branching upper growth
Care Guide
Watering
Water occasionally during prolonged dry spells to support growth
Fertilization
No regular fertilization required. Tolerates nutrient-poor soils; additional fertilization may encourage excessive, weak growth
Eggshell powder topdress：Sprinkle finely crushed, baked eggshells around the base to add calcium; avoid direct contact with stems to prevent irritationPruning
- Remove mature spiny burs before they disperse to prevent unintended seed spread
- Cut back dead above-ground stems in late autumn to reduce overwintering seed banks
- Thin dense growth in cultivated settings to improve airflow and reduce pest habitat
Toxicity
Warning: this plant may be toxic.
Pets & Humans
Pets: ASPCA: Toxic; ingestion may cause vomiting, diarrhea, lethargy, abdominal pain, and liver injury
Humans: Contains carboxyatractyloside; ingestion causes gastrointestinal distress, with severe cases potentially leading to liver damage
Garden Uses & Culture
Culture: N/A
Usage: N/A
