Biennial/Wildflower | Height: 30–60 cm | USDA Zones: 4–8 | Light: Full sun to partial shade
For optimal germination rates, initiate seed propagation indoors under controlled conditions—unless the species exhibits a high sensitivity to root disturbance. This approach allows precise regulation of temperature, humidity, and light, improving germination consistency and seedling viability. Do not skip any recommended seed treatments, as they are essential for uniform and successful germination.
Seed Treatment:
Cold stratification: Place seeds on a damp paper towel, seal in a plastic bag, and refrigerate for 4–6 weeks.
If seedlings emerge in the bag during stratification, carefully transplant them.
GA3 (Gibberellic Acid) can be used by experienced growers to bypass dormancy, but improper use may damage seeds. Use with caution.
Best Time to Sow:
• Indoors: Start 6–10 weeks before last frost (late winter to early spring)
• Outdoors: Sow in autumn or early spring
Germination Time: up to 30 days after stratification
Optimum Germination Temperature: Use a heat mat to maintain a steady temperature of 18–22°C (64–72°F)
Light Requirements for Germination:
12–16 hrs/day – Use grow lights if sowing indoors
How to Sow:
• Sow on the surface of moist seed-starting mix – do not cover seeds; they need light to germinate
• Mist gently to keep moist but not soggy
• 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:
• Provide strong light (sunny window or grow lights)
• Keep temperature steady and avoid overwatering
• Transplant outdoors after last frost once seedlings are strong enough to handle
Growing Tips:
• Prefers well-draining, moderately fertile soil
• Deadhead spent blooms to prolong flowering
• May self-seed in suitable conditions
• Supports pollinators and is excellent for cottage gardens and wildflower meadows