Seed Treatment
Cold Stratification:
Mix seeds with moist sand or place between a damp paper towel
Seal in a plastic bag and refrigerate at 35–40°F (2–5°C) for 4–6 weeks
Check weekly to keep moist (not soggy) and monitor for early germination
If seedlings sprout during stratification, gently remove and plant immediately
Best Time to Sow
Indoors: Late winter to early spring (after stratification)
Outdoors: Early spring or late fall (for natural stratification)
Germination Temperature:
Optimal: 65–70°F (18–21°C)
Germination Time: 21–30 days after stratification
Light Requirements for Germination
Requires 12–16 hours of bright light per day
Use grow lights if sowing indoors to ensure sufficient light exposure
Do not cover seeds with soil – light aids germination
Sowing Instructions
Press seeds gently onto the surface of moist, well-draining seed-starting mix
Use a humidity dome or cover with plastic to maintain moisture
Mist lightly to keep surface damp but never soggy
Post-Germination Care
Remove cover once seedlings emerge
Transplant when seedlings have at least 2 sets of true leaves
Harden off before moving outdoors by gradually exposing to outdoor conditions
Growing Tips
Prefers full sun
Grows in most soil types but thrives in moderately fertile, well-drained soil
Drought tolerant once established
Cut back after flowering to encourage a second bloom
Attracts beneficial insects and pollinators
Plant Height: 18–24 inches
Uses: Cottage gardens, borders, cut flowers, pollinator beds
USDA Zones: 3–8