Seed Treatment:
Cold Stratification:
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Place the seeds in a damp paper towel inside a sealed plastic bag and store them in the refrigerator at 35-40°F (2-5°C) for 1-2 weeks before planting.
Sowing Instructions:
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Timing:
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Direct Sowing (Preferred Method): Best sown in early spring (after the last frost) or fall (for blooms the following year).
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Indoor Sowing: Start seeds indoors 6-8 weeks before the last frost, then transplant outdoors.
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Soil Preparation:
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Choose a well-draining soil with neutral to slightly alkaline pH.
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If your soil is heavy, mix in sand or compost to improve drainage.
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Planting Depth:
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Sow seeds 1/8 inch (3 mm) deep.
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Lightly press the seeds into the soil but do not cover them too much, as they need light to germinate.
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Watering:
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Keep the soil evenly moist but not waterlogged.
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Avoid overwatering, as soggy soil can cause seeds to rot.
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Germination Conditions:
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Ideal temperature for germination: 50-60°F (10-15°C).
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Germination takes 10-20 days.
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Spacing:
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Thin seedlings to 6-12 inches (15-30 cm) apart once they develop strong roots.
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Sunlight Requirements:
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Prefers full sun, though it can tolerate light shade in hotter climates.
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Transplanting (If Started Indoors):
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Harden off seedlings for 7-10 days before transplanting outdoors to avoid shock.
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Handle roots carefully, as larkspur dislikes being transplanted.
Additional Tips:
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Self-seeding: Once established, larkspur will often self-seed and return year after year.
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Toxicity Warning: All parts of the plant are toxic if ingested, so keep it away from pets and children.
By following these steps, you should have beautiful larkspur blooms in late spring to early summer! ?