How to Grow China Asters (Callistephus chinensis) for Cut Flowers
Elegant, colorful, and endlessly versatile — China Asters (Callistephus chinensis) have long been a favourite among gardeners and florists. With their wide range of forms and colours, they easily fill late-summer gardens and bouquets with soft charm. But to get the very best stems for cutting, timing and care are key.
Let’s dive into their story, growing secrets, and the best ways to enjoy these beloved blooms.
A Short History
China Asters belong to the Asteraceae (Daisy) family and originate from East Asia — mainly China, Mongolia, and Korea.
In 1728, French missionary Nicolas-Joseph Incarville secretly sent seeds from China to Paris, sparking the plant’s European journey.
By the 19th century, breeding centres in France, Germany, and later the U.S. developed countless forms: from peony-flowered to chrysanthemum-type asters in every imaginable shade.
Today, new cultivars continue to appear from Poland, Denmark, Japan, and the Netherlands, keeping this classic flower fresh and exciting for modern gardeners.
Why Grow China Asters?
✅ Pros
- A huge variety of colours, shapes, and sizes – from soft pastels to vivid jewel tones.
- Excellent vase life – 7–10 days when harvested at the right stage.
- Strong stems and durable blooms – ideal for handling and transport.
- Long flowering window – they “hold” well in the field, giving flexibility for harvest.
- Often produce multiple stems per plant.
- Easy to grow from seed, suitable for both garden borders and professional cut-flower production.
⚠️ Cons
- Sensitive to day length – must be planted on time to achieve tall stems.
- Not ideal for succession planting – perform best when all are planted together early.
- Susceptible to Aster Yellows and Aster Rot – especially in warm, humid areas.
- Need careful rotation and hygiene to prevent disease buildup.
Choosing Varieties
When selecting seeds, make sure to choose tall varieties (minimum 60 cm / 24 in) bred specifically for cutting.
Many shorter types are designed for bedding or pot use and won’t give long stems.
Popular professional series include: Matsumoto, Tower, Chrisantella, Harlekin, Sea Starlet, Lady Coral, Valkyrie, and Syringa.
Each offers slightly different petal forms — from soft peony-like layers to narrow needle petals or perfect pompons.
How to Sow & Grow
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Sowing Indoors
- Start seeds 6–8 weeks before your last spring frost.
- Sow in trays, covering lightly (about 3 mm / ⅛ inch deep).
- Maintain +15–20 °C until germination (10–14 days).
- Keep the soil evenly moist but never soggy.
- When seedlings show true leaves, prick them out into separate cells or small pots.
Harden off plants gradually before transplanting outdoors.
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Transplanting
- Transplant after frost risk has passed and the soil has warmed.
- Timing is crucial: the plants must grow as much as possible before the Summer Solstice (around June 21).
After that, days shorten and stems stop elongating.
- Spacing: 20–30 cm between plants (closer spacing produces longer stems).
- Site: sunny, well-drained, fertile soil with pH 6.5–7.5.
- Watering: deep and regular, especially in dry spells.
- Feeding: apply balanced liquid fertilizer every 10–14 days during vegetative growth, but reduce nitrogen once buds appear.
Protecting from Pests & Diseases
- China Asters can be affected by:
- Leafhoppers and thrips – carriers of Aster Yellows virus.
- Fungal rots – including Fusarium and Rhizoctonia.
- Prevention tips:
- Use insect netting after transplanting to keep pests away.
- Rotate plantings — don’t grow asters in the same spot for at least 5–6 years.
- Avoid fresh manure or poorly decomposed compost.
- Remove and destroy any infected plants (do not compost).
- Support soil health with Trichoderma products or compost teas.
Care and Harvest
- Asters are sturdy, but netting helps keep stems straight in windy weather.
- Pinching is usually unnecessary — test only on a few plants if curious.
- Harvest when the outer petals are open, but the centres still tight.
- Remove lower leaves and condition stems in clean water with floral preservative.
- Properly grown asters reward you with long, straight, elegant stems — perfect for romantic summer and early-autumn bouquets.
Final Thoughts
China Asters bring the perfect bridge between summer and autumn in the flower garden.
Their vintage charm, wide palette, and long vase life make them indispensable for any cut-flower grower — whether you’re a home gardener or a professional florist.
With a little timing, good soil, and careful protection from pests, Callistephus chinensis will fill your garden — and your vases — with beauty, color, and nostalgia.
Explore our Therapy of Flowers selection of tall, florist-quality asters — from soft pastels to vibrant jewel tones.
Each packet includes fresh, high-germination seed and full sowing instructions.
