Seed Treatment:
• Cold stratification is recommended: Place seeds in a moist paper towel, sand, or vermiculite and seal in a plastic bag.
• Refrigerate at 35–40°F (1–4°C) for 2–4 weeks before sowing.
When to Sow:
• Indoors: Start seeds 8–10 weeks before last frost after stratification.
• Outdoors: Sow in early spring or fall for natural stratification.
Sowing Instructions:
• Surface sow — do not cover seeds, as they require light to germinate.
• Press gently into moist, well-draining seed-starting mix.
• Mist lightly to keep soil consistently moist (but not soggy).
• Ideal germination temperature: 60–70°F (16–21°C).
• Germination takes 21–35 days.
Light Requirements:
• Prefers partial shade.
• Can tolerate full sun in cooler climates with sufficient moisture.
Soil Requirements:
• Thrives in rich, moist, well-draining soil.
• Benefits from added compost or organic matter.
• pH range: 5.5–7.0 (slightly acidic to neutral).
Watering:
• Keep soil consistently moist, especially during germination and establishment.
• Astilbe is sensitive to drought—never let it dry out completely.
Spacing:
• Transplant seedlings to 12–18 inches (30–45 cm) apart when large enough to handle.
Growing Tips:
• Produces feathery, plume-like flower spikes in shades of pink, purple, or white in summer.
• Attracts bees and pollinators.
• Ideal for shade gardens, borders, woodland gardens, and along water features.
• Mulch to retain soil moisture and keep roots cool.
• Hardy perennial in USDA Zones 4–9.