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
Cold Stratification: Mix seeds with moist sand or peat moss in a sealed plastic bag. Refrigerate at 34–40°F (1–4°C) for 14–28 days (2–4 weeks).
Check weekly: If seeds sprout during stratification, plant them right away.
When to Sow Indoors
Start indoors 6–8 weeks (42–56 days) before your last expected frost.
When to Sow Outdoors (for Natural Stratification)
Sow directly in late fall or early winter. Press seeds into bare soil and let cold weather naturally stratify them.
Optimum Germination Temperature: Use a heating mat to maintain STEADY temperatures of 65–75°F (18–24°C)
Germination Time: 10–30 days (after stratification)
Light Requirements
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
Use trays or small pots with well-draining seed-starting mix. Gently press seeds into the surface without covering. Keep the soil moist (use a spray bottle) and maintain warmth and light.
Humidity
Use a humidity dome or clear cover to keep conditions moist. Open briefly once a day to allow airflow and prevent mold. Remove the dome once seedlings appear.
Post-Germination Care
Transplant when seedlings have 2–3 true leaves. Harden off before moving outside. Space 12–18 inches (30–45 cm) apart for good airflow.
Growing Tips
This hardy perennial grows 18–24 inches (45–60 cm) tall and thrives in full sun. Tolerant of drought and poor soil once established. No fertilizer needed. Blooms from late spring to fall. Deadhead to encourage more flowers. Loved by pollinators and perfect for wildflower gardens, borders, or meadow plantings.
Achillea millefolium (yarrow) is a low-maintenance, drought-tolerant perennial that attracts pollinators and makes an excellent addition to wildflower gardens, meadows, and borders!