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: Soak (Before Stratification)
Soak seeds in lukewarm water for 12–24 hours to soften the seed coat.
Step 2: Cold Stratification
Place soaked seeds in a moist paper towel, vermiculite, or peat moss.
Seal in a plastic bag and refrigerate for 4–6 weeks at 35–40°F (1–4°C).
Check occasionally to keep the medium moist (not soggy).
Check regularly: If seedlings sprout in the fridge, remove them gently and plant immediately.
When & How to Sow
Indoors: Start seeds 6–10 weeks before the last frost.
Outdoors: Sow in late fall for natural stratification (less common).
Sowing Depth: Surface sow or cover lightly — no more than ⅛ inch (3 mm). Press seeds gently into soil. They need light to germinate.
Soil: Use a well-draining, sterile, seed-starting mix with a bit of compost.
Ideal pH: 6.0–7.0 (slightly acidic to neutral).
Light: Use grow lights to maintain 12–16 hours of light per day.. Avoid harsh direct sun.
Watering: Mist gently to keep the soil evenly 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.
Germination Conditions
Temperature: Use a heat mat to maintain a steady temperature of 65–75°F (18–24°C)
Germination Time: up to 30 days after stratification
After Germination
Transplant when seedlings have 2–3 sets of true leaves. Space 12–18 inches (30–45 cm) apart.