Seed Treatment
Cold stratification is recommended to improve germination. Place seeds in a damp paper towel, seal inside a plastic bag, and refrigerate for 4–6 weeks. If seedlings begin to sprout during this time, remove them immediately and plant in soil.
When to Sow
Indoors: Start seeds in late winter to early spring.
Outdoors: Sow in fall for natural stratification or early spring after last frost.
Planting Depth & Spacing
Sow seeds just below the surface, about 1/8 inch (3 mm) deep. Cover lightly with fine soil. Space seedlings 6–10 inches (15–25 cm) apart when transplanting.
Germination Time
Germination can be slow and irregular. Expect sprouts in 6 to 12 weeks. Some seeds may wait until the second season to emerge, especially if dormancy hasn’t fully broken.
Optimal Temperature
Germinate at 60–70°F (16–21°C). Avoid temperatures above 75°F (24°C), which may hinder germination.
Light Requirements
Requires light to germinate—do not bury seeds too deep. Place trays in a bright location with indirect sunlight or under grow lights.
Watering
Keep soil evenly moist but not soggy. Mist gently to avoid disturbing seeds.
Post-Germination Care
Once seedlings appear, provide plenty of light and keep soil lightly moist. When seedlings are strong enough to handle, transplant to individual pots or outdoors after the danger of frost has passed.
Growing On
Alliums prefer full sun and well-draining soil. They thrive in garden beds, borders, or containers. Water moderately and avoid overly rich soil, which can reduce flower performance. Plants will naturalize over time and bloom in late spring to early summer with striking violet globes.
Tip
Patience is key—Allium seeds can take their time. Even slow starters may surprise you the following year!