Callistephus chinensis. King Size Mid-Blue China Asters make sensational cut flowers. The large, true blue flowers look amazing in the flower border, and incredible as a bouquet. The elaborate flowers open up to 8cm (3") across, with slightly curled petals. They top stems around 90cm (35") tall and bloom all summer. Be sure to take frequent harvests of cut flowers, or at least keep the plants dead-headed to prolong and enhance the bloom time. Please follow the planting and spacing instructions closely.
- Callistephus chinensis seeds
- 8cm (3") wide flowers
- Outstanding cut flowers
How to Grow China Aster
Step 1: Starting
Sow indoors 6-8 weeks before planting out, in peat pots or similar. Otherwise direct sow outdoors after the last frost date. Just cover the seeds. If starting indoors, provide bright light and a soil temperature of 18-21°C (65-70°F). China Aster seedlings are very susceptible to damping off, so provide good ventilation and only water from below.
Step 2: Growing
Space or transplant 30-45cm (12-18″) apart. This spacing is key to success later in the season, so please follow the guidance. Do not pinch back young plants. Water regularly during dry spells. This plant is particularly sensitive to over-watering, and will not thrive if over-crowded, poorly ventilated, or situated close to a heat-reflecting surface. Mulch around the plants in summer to help keep the roots cool.
Callistephus is prone to a bacteria-like organism known as aster yellows. If yellow spots become an obvious problem, destroy any infected plant before the condition spreads to others. Practice strict garden rotation with China Asters: never plant them in the same spot year after year.