Callistephus chinensis. Like its cousins in the rest of the King Size China Asters series, King Size Red are showy, and make superb cut flowers. The large, bright red flowers are luxuriant without going over the top. The elaborate flowers open up to 8cm (3") across, with slightly curled crimson petals. They top stems around 90cm (35") tall and bloom all summer. The plants are very upright in growth, with numerous multi-branching stems. 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.