Seed Treatment:
• Cold stratification is recommended.
• Mix seeds with moist sand or vermiculite, seal in a plastic bag, and refrigerate at 35–40°F (1–4°C) for 2–4 weeks.
• Alternatively, sow outdoors in late fall for natural winter stratification.
When to Sow:
Indoors:
• Start 6–8 weeks before the last expected frost
Outdoors:
• Direct sow in early spring or late fall
Light Requirements:
• Prefers full sun, but tolerates light shade, especially in hot climates
Soil Requirements:
• Thrives in well-drained, moderately rich soil
• Avoid heavy clay or overly wet soil
• pH range: 6.0–7.5
Sowing Instructions:
• Surface sow — do not cover seeds, as they need light to germinate
• Press gently into the surface of moist seed-starting mix
• Keep temperature at 65–70°F (18–21°C)
• Germination time: 14–21 days
Watering:
• Keep soil consistently moist but not soggy during germination
• Once established, drought-tolerant and prefers slightly dry conditions between waterings
Spacing:
• Thin or transplant seedlings to 12–18 inches (30–45 cm) apart
Growing Tips:
• Named for its unique balloon-like buds that open into star-shaped blue, pink, or white flowers
• Blooms from mid-summer through fall
• Great for borders, cottage gardens, and containers
• Pinch back young plants to encourage bushier growth
• Long-lived perennial; once established, avoid disturbing the roots
• Hardy in USDA Zones 3–8