Perennial | Bell-shaped flowers | Attracts pollinators
Seed Treatment
Cold Stratification: Place seeds on a moist paper towel, fold it, and seal in a labeled ziplock bag. Refrigerate at 4°C (39°F) for 3–4 weeks. Check weekly — if seedlings emerge early, gently transplant into soil.
GA3 (Gibberellic Acid) may stimulate germination but can destroy seeds if misused — only use if experienced.
When to Sow
Indoors: Start in late winter to early spring (January–April).
Outdoors: Sow in late fall to early winter (October–January) for natural cold stratification. Only suitable in regions with consistent winter temps between 0–5°C (32–41°F).
Optimum Germination Temperature: 18–22°C (65–72°F)
Germination Time: Up to 30 days after stratification
Light Requirements for Germination
Seeds need light to germinate. Do not cover with soil.
Use grow lights to maintain 12–16 hours of light per day.
How to Sow Indoors
- Surface sow on moist, well-draining seed-starting mix
- Press gently to ensure contact
- Mist to avoid dislodging seeds
- Cover with a clear dome or wrap to retain moisture
- Remove cover once seedlings emerge
Post-Germination Care
- Move seedlings to bright, indirect light
- Water from below or mist to prevent damping off
- Transplant when 2–3 true leaves appear
- Harden off before moving outdoors (gradual exposure over 7–10 days)
Outdoor Stratification
For fall/winter sowing: sow on moist soil or in seed trays left outdoors. Cover lightly or protect with mesh. In spring, once temperatures rise, germination begins naturally.
If seedlings emerge during stratification, remove them from the bag and plant right away.
Growing Tips
- Space plants 30 cm (12 in.) apart
- Prefers full sun to partial shade
- Grows best in well-drained, neutral to alkaline soil
- Cold hardy; regrows in spring
- Deadhead to prolong flowering