Grey moor grass

Grey moor grass: how do you recognise it?

Habit

Dense, upright clump about 50 cm tall and 40 cm wide, gradually getting bigger.

Foliage

Stiff, narrow and straight; grey-blue and evergreen, with a finely pointed tip.

Flower

Slender, silvery spikes in April–May, just above the foliage.

Season

A cool-season grass: it grows mainly in spring and autumn and stays grey-blue in winter.

Roots

Fibrous and deep, perfectly adapted to dry mountain slopes.

Flowering: April–May · Plants: March–May and September–October · Pruning: March

Why grow it?

• Grey-blue, evergreen foliage that looks good all year, even in winter.
• Tolerates drought and poor, chalky soil: ideal for sunny, dry spots.
• Compact, neat clumps of about 50 cm: suitable for borders, rock gardens, gravel gardens and containers.
• Silvery flower spikes in April–May, a soft display that never jars.
• Low maintenance: just comb out or trim the old leaves in spring.

Grey moor grass: where does it grow best?

• Sun to half shade: the sunnier the spot, the bluer the foliage.
• Well-drained soil: sand, loam or clay, neutral to chalky. It tolerates poor, stony soil.
• Dry: once established it copes with drought. It does not tolerate wet, heavy soil.
• Ideal in a rock garden, a gravel bed or at the foot of a sunny wall.
• Allow 30–40 cm between plants.

Light

Sun and partial shade

Soil type

Sand, loam or clay

Acidity

Neutral or chalky

Moisture

Dry

Size

0.5 m tall, 0.4 m wide

Hardiness

Hardy (to -20 °C)

Goes well with

• Lavender: Purple flowers and fragrance, in the same dry, chalky sun.
• Sage (Salvia): Purple flower spikes in late spring and summer, on the same dry soil.
• Stonecrop (Sedum): Fleshy leaves and late-summer flowers in the same spot.
• Spurge (Euphorbia): Yellow-green flowers in spring, lovely next to the grey-blue foliage.
• Creeping thyme: A low, fragrant mat between the clumps on dry soil.

Grey moor grass: when and how to plant it?

Plant in March–May and September–October.

1. Plant in March–May or in September–October, when the soil is neither frozen nor waterlogged.
2. Dig a hole twice as wide as the root ball. On heavy soil, mix in plenty of coarse sand or grit.
3. Set the plant at the same depth as in its pot and no deeper: the heart of the clump must stay above the soil.
4. Leave 30–40 cm between plants.
5. Water in thoroughly straight away, then weekly in dry weather during the first year.
6. Cover the soil around the plants with a layer of gravel, keeping the heart clear.

Care

Water

Only in the first year during dry spells. After that it copes by itself, even in a dry summer.

Feeding

Not needed: on poor, dry soil it stays compact and blue.

Tidying

In March, pull the old brown leaves out of the clump with your fingers or a small rake, or trim them off.

Mulching

A layer of gravel keeps the base dry and suppresses weeds.

Dividing

If the heart of the clump turns bare, divide it in April (every 4–5 years).

Tip: Plant it on dry, chalky soil and do not feed. Remove only the old leaves: an evergreen clump that is cut too short recovers slowly.

Grey moor grass: when to prune it?

Pruning months: March.

When: In March, before the flower spikes appear.

How:

• Remove the dead, brown leaves from the clump with your (gloved) fingers or a small rake.
• Trim off only the old, withered leaves; leave the green ones.
• The trimmings can go on the compost heap.

Caution: Never cut the clump right down: the evergreen foliage is its beauty and its winter protection.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In April–May (or in September): split a clump with a sharp spade into pieces, each with roots and leaves, and replant straight away at the same depth. Water well.

Seed

Sow in spring on seed compost, barely cover and keep lightly moist. Seedlings grow slowly at first: division is quicker.

Grey moor grass: how does it get through the winter?

Hardy to −20 °C.

• Hardy to about −20 °C: in Belgium protection is usually not needed, and the foliage stays grey-blue.
• Wet winters on heavy soil are more dangerous than frost: ensure good drainage or plant on a mound.
• In a pot: stand it on feet, keep it out of winter rain and wrap the pot in hessian in severe frost.

Diseases and pests

• Rotting: On wet, heavy soil the clump can rot away in winter. Improve drainage with coarse sand or grit, or plant on a mound.
• Floppy, open clump: Caused by too much shade, feed or water. Move to a sunny, dry spot and do not feed.
• Brown, dead leaves: Normal: old leaves die and stay in the clump. Remove them in March.
• Bare centre: An old clump dies out in the middle. Divide it in April and replant the young outer pieces.

Through the year

• March: Comb out old leaves before the flower spikes appear. Plant.
• April: Flowering begins. Plant or divide.
• May: In flower with silvery spikes. Plant.
• June: Quiet growth. Water young plants in long dry spells.
• September: Plant. Keep the soil slightly moist.
• October: Plant. Mulch with gravel.
• November: Resting, the foliage stays grey-blue.
• December: Evergreen: the clumps decorate the garden.

Did you know?

• The species name nitida means ‘shining’ in Latin.
• In the wild it grows on dry, chalky mountain grasslands in Italy.
• Sesleria are cool-season grasses: they grow mainly in spring and autumn and slow down in hot summers.