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.
⚠️ Keep soil evenly moist during germination. DO NOT LET IT DRY OUT—once seeds begin absorbing water (imbibition), drying can kill the seed embryo, and even brief dryness after sprouting can kill seedlings.
Seed Preparation:
1. Soak seeds in lukewarm water for 4–6 hours.
2. Cold Stratification: Place the seeds in a damp paper towel in a ziplock for 7 days in the refrigerator.
If seedlings emerge during stratification, plant immediately.
Best Time to Sow
Indoors: 6–8 weeks before your last frost (Jan–Mar depending on zone)
Outdoors: After danger of frost has passed (Apr–May)
Germination Conditions
Germination time: up to 21 days after cold stratification
Optimum temperature: 18–21°C (65–70°F)
Daylight needs: Use grow lights to provide 12–14 hours of light per day
Planting Instructions
Sow lightly on surface – press in, do not cover heavily or cover lightly with vermiculite.
Water: Mist gently to keep soil moist (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.
After Germination
Move seedlings to bright light or south-facing window
Transplant: Once seedlings have 2–3 true leaves, harden off gradually
Spacing: 20–25 cm (8–10") apart in garden beds or containers
Soil: Well-draining, loamy soil with pH 6.0–7.0
Bloom Time: Spring through summer in temperate climates
Growing Tips
Deadhead regularly to encourage more blooms
Tolerates light frost; mulch base if overwintering outdoors
Ideal for borders, containers, or cottage gardens
More guides at: bloomoutlet.com/seed-guides