How to Grow China Aster
Callistephus chinensis
China asters are half-hardy annuals grown fresh from seed each year for their showy, long-lasting cut flowers. Sow indoors 6 weeks before last frost or direct sow after all frost risk has passed. They need full sun, fertile well-drained soil, and consistent moisture. Pinch tips early for bushier plants with more blooms. Crucially, rotate the planting site every year to avoid Fusarium aster wilt which persists in soil.
In your Leaftide garden - Hardiness
- Half Hardy
- Season
- Warm Season
- Spacing
- 30 cm
- Height
- 60 cm
- Sow depth
- 0.5 cm
- Min. soil temperature
- 15°C+
- Start from
- Seed
- Light
- Full sun
- Water
- Moderate
When to Start
Sow indoors 6 weeks before last frost, or direct sow outdoors after frost risk has passed and soil reaches 15°C.
Don't know your frost date? Find it here →
Growth Stages
Approximate days from start
Care Essentials
- Liquid feed fortnightly once buds appear; use a balanced or high-potash fertilizer.
- Rotate planting site annually to prevent aster wilt buildup. Excellent cut flower lasting 7-14 days in a vase.
Growing Conditions
- Min. soil temperature
- 15°C+
- Germination temperature
- 18–22°C
Pet Safety
- Sow indoors
- —
- Transplant out
- —
- First harvest
- —
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Spacing & Planting
| Plant spacing | 30 cm |
| Row spacing | 40 cm |
| Sow depth | 0.5 cm |
| Mature height | 60 cm |
| Mature spread | 30 cm |
Taller varieties benefit from 35-40cm spacing for air circulation to prevent disease.
Growing Conditions
| Min. soil temperature | 15°C |
| Germination temperature | 18–22°C |
| Base growth temperature | 10°C |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant China Aster?
- Plant China Aster 30cm apart with 40cm between rows.
- When does China Aster flower?
- China Aster typically flowers approximately 70 days after transplanting.
- Is China Aster frost hardy?
- China Aster is classified as Half Hardy.