Giant bentgrass
Agrostis gigantea · Poaceae
The gardener's calendar
Ideal time to plant giant bentgrass: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Family
- Poaceae (grasses)
- Type
- Perennial grass
- Mature height
- 60 to 120 cm
- Foliage
- Deciduous to semi-evergreen
- Flowering
- June to September
- Hardiness
- Very hardy (down to -20 °C)
- Origin
- Temperate Europe and Northern Asia
- Growth
- Fast
Care
Light exposure
Giant Agrostis prefers full sun or partial shade. It tolerates variations in light well but produces denser foliage and more abundant flowering in the sun. Avoid heavily shaded areas that slow its growth.
Watering
Water regularly while the plant is establishing itself, then moderately once established. This grass tolerates dry periods well thanks to its well-developed root system. In very arid climates, weekly watering in summer remains beneficial.
Soil
Giant Agrostis adapts to most soils, from sandy to loamy, provided they are not waterlogged. Well-draining soil is preferable. The plant tolerates poor soils, but adding organic matter in spring promotes vigor.
Pruning and cleanup
Cut back the clump to ground level in late winter (February-March) before growth resumes. This revitalizes the plant and removes dried culms. You can also regularly remove dead leaves at the base during summer.
Fertilizing
A balanced fertilizer application in spring is generally sufficient. In poor soil situations or intensive plantings, a light second application in June supports growth. Avoid excess nitrogen, which promotes fungal diseases.
Diseases and pests
Giant Agrostis is generally robust but can be susceptible to powdery mildew and rust in excessively humid conditions. Ensure good air circulation and avoid overhead watering. Properly drain stagnant areas to prevent root rot.
Did you know?
Giant Agrostis lives up to its name: unlike most of its more modest agrostis cousins, it can reach over one meter in height, making it an impressive grass for contemporary gardens. In Europe, it has long been used to stabilize riverbanks and degraded slopes, thanks to its powerful and highly anchoring root system.
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
- Tufted hair grassDeschampsia cespitosa
- Wavy hair-grassAvenella flexuosa
- 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.