Seed Treatment (Cold Stratification Required)
How to Stratify:
- Moisten a small amount of vermiculite, sand, or peat moss (just damp, not wet).
- Mix seeds with the moist medium in a resealable plastic bag.
- Place in the refrigerator at 35–40°F (1–4°C) for 6–8 weeks.
- Check occasionally to ensure medium remains moist and free of mold.
- After stratification, sow seeds immediately.
Sowing Instructions
- When to Sow:
- Indoors: Start seeds in late winter to early spring after stratification.
- Outdoors: Sow in fall for natural cold stratification.
- Soil Requirements:
- Use well-draining, sandy or loamy soil.
- Avoid waterlogged conditions.
- Ideal pH: 6.0–7.5 (neutral to slightly acidic/alkaline).
- Light Requirements:
- Prefers full sun (6–8 hours daily) for best flower production.
- Sowing Depth:
- Sow seeds ¼ inch (6 mm) deep.
- Lightly cover with fine soil and gently firm down.
- Watering:
- Keep the soil evenly moist but not soggy during germination.
- Once established, Allium plants are drought-tolerant and require minimal watering.
- Germination Time:
- Germination can take 30–90 days or longer — patience is key.
- Ideal temperature post-stratification: 60–70°F (15–21°C).
- Spacing & Transplanting:
- Once seedlings have several true leaves, transplant to individual pots or garden beds.
- Final spacing: 8–12 inches (20–30 cm) apart.
Growing Tips
- Allium aflatunense hollandicum produces globe-shaped purple flower heads on tall, upright stems — perfect for cut flowers and pollinator gardens.
- Leaves may yellow as the plant blooms — this is normal.
- Deer- and rodent-resistant, and attracts bees and butterflies.
- Blooms in late spring to early summer.
- Allow seed heads to dry on the plant for decorative interest or seed collection.
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