Autumn moor grass

Autumn moor grass: how do you recognise it?

Habit

Dense, rounded clump 30–40 cm tall and wide.

Leaves

Narrow, flat, light green to yellow-green and evergreen.

Flowers

Slender, silvery white spikes on thin, straight stems above the leaves, in August–October.

Roots

Fibrous and deep-reaching; they make the plant drought-tolerant.

Growth

Spreads slowly and self-seeds only a little, if at all.

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

Why grow it?

• Evergreen: fresh green clumps all year round.
• Silvery white spikes in autumn, when many other plants have finished flowering.
• Tolerates dry soil, sun and part shade, even under trees.
• In large groups it makes a dense, low-maintenance ground cover.
• Neat, rounded clumps that do not flop or spread aggressively.

Autumn moor grass: where does it grow best?

• Sun to part shade; in full sun the leaves are slightly more yellow.
• Free-draining soil: sand, loam or clay, neutral to chalky.
• Dry to moist but not wet; it does not tolerate wet feet in winter.
• As ground cover, plant 30–40 cm apart in a staggered pattern so the clumps knit into a carpet.

Light

Sun and partial shade

Soil type

Sand, loam or clay

Acidity

Neutral or chalky

Moisture

Dry or normal

Size

0.4 m tall, 0.4 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Michaelmas daisy: Blue or white flowers at the same time as the silver spikes.
• Japanese anemone: Pink or white autumn flowers in the same part shade.
• Ice plant: Pink flower heads in late summer, just as drought-tolerant.
• Crocus: Spring flowers that come up between the green clumps.
• Cranesbill: Flowers in summer between the clumps and also copes with dry shade.

Autumn moor grass: when and how to plant it?

Plant in March–May and September–October.

1. Plant in March–May or in September–October.
2. Loosen the soil and remove perennial weeds thoroughly: weeding between the clumps is awkward later.
3. Set the plants at the same depth as in the pot.
4. Plant 30–40 cm apart in a staggered pattern, about 6–11 plants per m².
5. Water well after planting and in dry spells during the first year.
6. Mulch between the clumps with fine wood chips or gravel until they close up.

Care

Water

In dry spells during the first year. After that only in long droughts, especially under trees.

Feeding

Not needed.

Tidying

In March, comb the dead leaves out of the clumps.

Rejuvenating

If the clumps look untidy after some years, cut them back to 10 cm in March; they regrow quickly.

Weeding

Keep the area weed-free in the first year until the clumps close up.

Tip: Plant it closely, 30–40 cm apart in a staggered pattern, and keep the soil weed-free in the first year: after that it forms an evergreen carpet that needs almost no work.

Autumn moor grass: when to prune it?

Pruning months: March.

When: Evergreen: only tidy it in March. Every few years you can also cut it back to 10 cm at that time.

How:

• Comb the dead leaves out of the clumps with your fingers or a rake.
• Cut away last year’s old flower stems.
• If the clumps are bare or untidy, cut them back to 10 cm in March, before new growth starts.

Caution: Do not cut it back in autumn or winter: you would lose the green winter foliage.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In March–April or September, lift a clump and split it with a spade into pieces, each with good roots.

Seed

It sometimes self-seeds a little; move the seedlings in spring.

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

Hardy to −25 °C.

• Hardy to about −25 °C: no protection is needed in Belgium.
• The clumps stay green all winter, although the leaves may brown a little after hard frost.
• Heavy, wet soil is more dangerous than frost: make sure drainage is good.

Diseases and pests

• Yellow leaves: The leaves are naturally yellow-green, especially in sun: this is not a deficiency.
• Rot: Clumps die after a wet winter in heavy soil. Plant it in a free-draining spot.
• Weeds between clumps: Until the clumps close up. Mulch between the plants and weed in spring.
• Brown leaf tips: After hard frost or drought. Comb out or cut back in March.

Through the year

• March: Comb out dead leaves, every few years cut back to 10 cm. Plant and divide.
• April: Plant. Weed between the clumps.
• May: Plant. Water in dry spells.
• June: Fresh green clumps. Weed until they close up.
• August: Flowering begins: silvery white spikes.
• September: Flowering. Plant and divide.
• October: Last flowers. Plant.
• December: Evergreen clumps in the winter garden.

Did you know?

• The genus Sesleria is named after Leonardo Sesler, an eighteenth-century physician and botanist from Venice.
• Most moor grasses flower in spring; this one flowers in autumn, hence the name autumnalis.
• It is one of the few ornamental grasses that grow well both in full sun and in dry shade under trees.