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
Step 1: Cold Stratification
Mix seeds with moist sand or place on a damp paper towel inside a sealed plastic bag. Refrigerate for 14–28 days (2–4 weeks) at 1–4°C (34–40°F). Check periodically to ensure the medium stays moist but not soggy.
Check regularly: If seedlings sprout in the fridge, remove them gently and plant immediately.
Step 2: After stratification, soak seeds in lukewarm water for 6–8 hours.
When to Sow Indoors
Start seeds indoors 10–12 weeks (70–84 days) before your last expected frost date.
How to Sow Indoors
Sow on the surface of moist seed-starting mix. Press gently for good contact—do not cover, as light aids germination.
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.
Light Requirements for Germination
Light is required. Use grow lights to maintain 12–16 hours of light per day.
Optimum Germination Temperature: Use a heat mat to maintain a steady temperature of 18–22°C (65–72°F)
Germination Time: Up to 35 days after stratification
Post Germination Care
When seedlings have 2–3 true leaves, transplant into individual pots. Harden off gradually before planting outdoors.