Calamagrostis acutiflora
Calamagrostis acutiflora · Poaceae
The gardener's calendar
Calamagrostis acutiflora is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Family
- Poaceae (grasses)
- Foliage type
- Deciduous to semi-evergreen
- Flowering
- July to September
- Adult height
- 120 to 150 cm
- Adult spread
- 60 to 90 cm
- Growth
- Fast
- Hardiness
- Very hardy (-25 °C)
- Origin
- Central and Eastern Europe
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
This grass produces its finest spikes if you cut it back hard in February-March before growth resumes. Well-drained soil in winter is enough; don't over-enrich.
The common mistake
Failing to prune in late winter means dead wood accumulates, flowering diminishes, and the plant eventually collapses.
The pro's trick
Leave the spikes all autumn and winter for structure and landscape interest; only prune in March before new shoots emerge.
Care
Exposure
Calamagrostis acutiflora develops perfectly in full sun, ideally at least 6 hours of direct sunlight. It tolerates partial shade but will be less vigorous and less floriferous. Avoid overly shaded spots that would slow its growth and distort its shape.
Watering
Water regularly the first year after planting to promote root establishment. Once established, this grass is very drought-tolerant and only requires regular watering during prolonged heat waves. Drastically reduce watering in autumn and winter.
Soil
Plant in well-draining soil, even poor or chalky: this grass adapts to most soil types. Avoid constantly wet or waterlogged ground which causes rot. Ordinary garden soil is sufficient, with no special amendment needed.
Cutting and pruning
Cut short in late winter (February-March) before new growth, to about 10-15 cm from the ground. Wear gloves: the leaves are sharp. Remove faded inflorescences in autumn if preferred, but leaving the dried foliage offers a beautiful winter presence and protects the heart of the plant.
Fertilizer
Once established, this grass requires no regular fertilizer. A light annual application in spring (balanced fertilizer or compost) during weeding is sufficient. Avoid excessive nitrogen which weakens the plant's structure and makes it more prone to lodging.
Diseases and pests
Calamagrostis is very resistant and rarely affected by diseases. Prolonged excess moisture can promote root rot. Regularly aerate the heart of the clump by removing debris and avoiding excessive watering.
Did you know?
Calamagrostis acutiflora has become one of the most popular ornamental grasses in modern landscape architecture since the 1990s, notably thanks to the work of German landscape architect Dieter Kienast. Its feathery and airy inflorescences, lightly tinged with pink in early summer, sway gracefully in the wind, creating constant movement that animates gardens even in the depths of winter when the foliage has dried.
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.
Add this plant to my garden →Plants from the same family
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- Purple moor-grassMolinia caerulea
- Reed canary-grassPhalaris arundinacea
- Common quaking grassBriza media
- Creeping soft-grassHolcus mollis
Tips generated and checked by Viridia — adapt them to your local climate.