Seed Treatment
Cold stratification: Place seeds on a damp paper towel, seal in a plastic bag, and refrigerate for 30 to 90 days.
If seedlings emerge during stratification, remove and plant them immediately.
Optional: GA3 (Gibberellic Acid) may be used only if you're experienced—improper use can destroy seeds. Use very low concentrations (50-250 ppm) for a short soak (4-6 hrs).
When to Sow
Indoors: Start 8–10 weeks before last frost.
Outdoors: Direct sow in fall or very early spring for natural stratification.
Germination Time: up to 30 days (AFTER stratification)
Optimal Germination Temp
21–24°C (70–75°F)
Light for Germination
Requires light to germinate. Sow on the surface—do not cover with soil.
Provide 12–16 hrs/day of light. Use grow lights if sowing indoors.
How to Sow
Use sterile seed-starting mix in trays or pots. Press seeds onto moist surface without covering. Mist gently to avoid dislodging.
Humidity: Use a humidity dome or clear cover to maintain consistent moisture during germination. Open the dome briefly once per day to allow fresh air in and reduce mold risk. Remove the dome entirely once seedlings emerge.
Post-Germination Care
Remove cover as soon as seedlings appear (10–20 days). Provide strong light and good air circulation. Keep soil moist but not soggy. Transplant when seedlings have 2–3 true leaves.
Growing Tips
- Full sun (6–8 hrs/day)
- Well-drained soil
- Drought tolerant once established
- Blooms in the second year from seed
- Attracts bees, butterflies, and birds
- Deadhead to extend bloom season, or leave seed heads for birds
Final Height: 60–120 cm (24–48 in)
USDA Zones: 3–9
Uses: Cottage gardens, pollinator beds, medicinal herb borders