PlantFun
Plant Needs
Sunlight
Full sun to partial shade; thrives in open, sunny garden beds and tolerates light shade in hot summer climates.
Watering
Allow the top 2–3 cm of soil to dry completely between waterings; drought-tolerant once established and resistant to brief dry spells.
Temperature
Extremely cold-hardy, surviving harsh winter temperatures; tolerates moderate summer heat without significant stress.
Characteristics
- Leaf: Lower leaves are lobed, upper leaves are linear to lanceolate with serrated margins, dark green and slightly hairy.
- Flower: Dense whorls of small pink to purple tubular blooms clustered along upper stems.
- Stem: Square, hairy upright branching stems characteristic of the mint family.
Care Guide
Watering
Keep soil slightly moist during active growth periods; avoid overwatering to prevent root rot
Fertilization
Apply diluted organic feed once monthly to support growth. Use low-nitrogen feed to promote flowering rather than excessive foliage growth.
Eggshell powder topdress：Crush dried eggshells into fine powder, sprinkle lightly on soil surface, and gently work into top layer; avoid direct contact with stems to prevent irritation.Pruning
- Deadhead spent flower spikes to extend the flowering season and prevent self-seeding in managed gardens.
- Cut back all stems to 10 cm above soil level in late autumn to encourage healthy regrowth in spring.
- Thin overcrowded clumps in early spring to improve airflow and reduce fungal disease risk.
Toxicity
Warning: this plant may be toxic.
Pets & Humans
Pets: ASPCA: Toxic due to alkaloids and iridoid glycosides; ingestion may cause adverse systemic effects.
Humans: Excessive ingestion may cause nausea, dizziness, and mild gastrointestinal upset; used medicinally in controlled doses.
Garden Uses & Culture
Culture: Used in traditional European and Asian medicine to support menstrual health and cardiac function.
Usage: Medicinal herb, pollinator garden plant to attract bees and butterflies, and wildflower meadow component.
