Northern bentgrass
Agrostis mertensii · Poaceae
The gardener's calendar
Ideal time to plant northern bentgrass: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Family
- Poaceae (grasses)
- Plant type
- Ornamental grass
- Foliage
- Deciduous to semi-evergreen depending on climate
- Flowering
- Summer (June to August)
- Mature size
- 30 to 60 cm in height
- Growth
- Moderate
- Hardiness
- Good in temperate climates
- Origin
- Falkland Islands and Patagonia
Care
Light
Mertens' bentgrass appreciates full sun to partial shade for optimal development. In very hot climates, some afternoon shade can prevent excessive drying. Avoid completely shaded areas where the plant becomes less compact.
Watering
Keep the soil regularly moist during the active growing period, without creating waterlogging. Once established, this grass tolerates short dry spells well. In winter or during dormancy, gradually reduce watering.
Soil
Mertens' bentgrass prefers well-draining, rather cool and slightly acidic to neutral soil. Enrich the soil with compost or potting soil at planting to promote rooting. Improve drainage with sand or gravel if your soil is naturally clayey.
Pruning and maintenance
Cut back the clump in early spring, before new growth begins, cutting to 10-15 cm from the ground. Regularly remove dead or damaged leaves to keep the plant airy. This grass requires only minimal maintenance once established.
Fertilization
Apply balanced or grass-specific fertilizer in spring when growth resumes. One annual application is generally sufficient for healthy plants. Avoid excess nitrogen which would make the plant too lax.
Diseases and pests
Mertens' bentgrass is generally robust and not very susceptible to diseases if drainage conditions are correct. Watch for root rot in case of stagnant excess moisture. Good air circulation prevents most fungal problems.
Did you know?
Mertens' bentgrass is named after German botanist and naturalist Franz Carl Mertens (1764-1831). This grass native to Tierra del Fuego fascinates horticulturists with its ability to thrive in windswept coastal and cold environments, where it provides an elegant alternative to the usual tropical grasses.
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.