Incised-leaf aster
Kalimeris incisa · Asteraceae
📷 Hectonichus · CC BY-SA 3.0
The gardener's calendar
Incised-leaf aster is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Scientific name
- Kalimeris incisa
- Family
- Asteraceae
- Plant type
- Herbaceous perennial
- Foliage
- Deciduous
- Flowering
- July to September
- Adult height
- Approximately 60 cm
- Origin
- Japan, Korea
- Hardiness
- Very hardy (down to -15°C)
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability medium.
Expert tips
The key tip
Kalimeris incisa wants full sun and normal to dry soil. Water moderately during growth.
The common mistake
Overwatering or over-fertilizing with nitrogen: the plant becomes soft, prone to disease, and flowers poorly.
The pro's trick
Divide clumps as soon as March when it emerges: this rejuvenates the plants and encourages denser, longer flowering from July to September.
Care
Sunlight
Plant Japanese aster in full sun for generous flowering and a compact plant. It tolerates partial light shade but will flower less abundantly. An airy location limits fungal issues.
Watering
Keep the soil regularly moist during the growing period, without waterlogging. Once established, the plant tolerates moderate dry periods. Water more generously in summer during heat waves.
Soil
Prefer well-drained, fertile, and slightly moist soil. Japanese aster adapts to most soils but appreciates organic matter worked in at planting time. Avoid compacted and poorly draining soils.
Pruning and maintenance
Pinch back the tips in June to promote a compact shape and better branching. After flowering, remove faded stems at soil level in autumn or early spring. Divide the clump every 3 to 4 years.
Fertilizing
Apply balanced fertilizer in spring when growth restarts. Moderate feeding is sufficient; excess nitrogen favors foliage at the expense of flowers. A fertilizer formulated for perennials is recommended.
Diseases and pests
Generally robust, Japanese aster can be affected by powdery mildew in case of excessive humidity and poor air circulation. Ensure adequate spacing and avoid overhead watering. Aphids and spider mites are possible during hot, dry weather.
Did you know?
Japanese aster was once classified in the genus Aster, which includes over 600 species and takes its name from the Greek word 'astēr' meaning 'star,' referring to the shape of its small flowers. Kalimeris incisa has been highly prized by Japanese and Chinese gardeners for centuries for its late flowering, which extends color in gardens as autumn approaches.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
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Tips generated and checked by Viridia — adapt them to your local climate.