Marram grass

How to recognise it

Habit

Large, stiff tussocks of 60–120 cm, linked by long horizontal and vertical rhizomes.

Leaf

Grey-green, stiff and long, rolled into a tube with a sharp, prickly tip. The inner surface is deeply ridged. The ligule is strikingly long, 1–3 cm, and pointed.

Flower

Dense, cylindrical, spike-like panicle of 10–20 cm, pale straw-yellow, from June to August.

Roots

An extensive network of rhizomes and roots that can reach metres deep into the sand.

Confusion with

Lyme grass has broad, flat, blue-grey leaves and a true spike. Wood small-reed has flatter leaves and a looser, purplish-brown panicle, and also grows inland.

Flowering: June–August · Pruning: March

Why grow it?

• It builds dunes: it traps blown sand and grows up through it again and again, so the dunes become higher.
• A natural coastal defence, planted for centuries along the North Sea.
• Dune insects, spiders and small animals find shelter from sun and wind between the tussocks.
• The open sand between the marram tussocks is a nesting site for mining bees and digger wasps.
• A tough, graceful grass for a sunny, sandy garden on the coast.

Marram grass: where does it grow best?

• In the wild: the foredunes and young, shifting dunes along the coast, where fresh sand blows in every year.
• Full sun and wind.
• Pure, dry, poor sand; tolerates salt-laden wind, but not flooding by seawater.
• In the garden: only on pure, dry sand in full sun, for example in a coastal garden or on a sandy mound; in ordinary garden soil it dwindles.

Goes well with

• Sea buckthorn: Orange berries in autumn for birds, on the same dry sand.
• Lyme grass: Blue-grey leaves as a contrast to the grey-green marram.
• Biting stonecrop: Low yellow flowers in June on bare sand.
• Burnet rose: Low, prickly rose with white flowers and black hips.
• Sea holly: Blue-grey, spiny flower heads; buy only from a nursery.

Marram grass: when and how to plant it?

1. Never pull up or dig out marram in the dunes: the dunes are protected nature areas and marram holds the sand in place. Buy plants from a nursery.
2. Plant from November to March, when the sand is moist and the plant is dormant.
3. Dig a hole 20–30 cm deep and set the plant deeper than it was in the pot: marram tolerates being buried.
4. Plant in a grid, 30–50 cm apart, for dense cover that holds the sand.
5. Do not add compost or potting soil: marram likes poor sand.
6. Water when planting; after that it is no longer needed.

Care

Watering

Never needed once established.

Feeding

Do not: fertiliser helps other plants that crowd out marram.

Fresh sand

In a garden without blowing sand, scatter a thin layer of fresh sand around the tussocks each spring to keep them vigorous.

Tidying

In March, comb dead leaves out of the tussock with a rake or gloved hands.

Spreading

The rhizomes creep far in loose sand. Cut off runners outside the desired area with a spade.

Tip: Marram only really thrives when it gets buried a little: in a sand garden, scatter a few centimetres of fresh sand over the tussocks every spring.

Pruning and mowing

Pruning months: March.

When: In March, before new growth starts, and only if you want to remove dead leaves.

How:

• Comb the dead, grey leaves out of the tussock with gloved hands or a rake.
• Cut off old flower stems just above the foliage.
• Never cut marram short: the tussock loses vigour and the sand is left bare.

Caution: Wear sturdy gloves: the leaf tips are sharp and prickly.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In late autumn or winter, cut off a piece of rhizome with a few shoots and plant it deep in sand. This is also how marram is planted on the coast.

Seed

Ripe in August–September. Sow in spring in moist sand; this is slower than division.

Marram grass: how does it get through the winter?

Hardy to −25 °C.

• Marram stays standing in winter; the leaves turn greyer and straw-coloured.
• Fully hardy, to about −25 °C, and resistant to storms and blowing sand.
• Even in winter storms the tussocks hold the sand and shelter small animals.

Diseases and pests

• Decline: Without fresh blown sand or in rich soil, marram loses vigour. Choose pure sand and add a layer of sand now and then.
• Trampling: Walking on it breaks the tussocks and sets the sand moving. Stay on the paths in the dunes; in the garden, lay a path.
• Too wet: On wet or heavy soil it rots. Plant only in free-draining sand.
• Prickly leaves: The leaf tips are sharp: do not plant it next to a play area or seating.

Through the year

• January: Plant in sand during mild weather.
• February: Plant or divide.
• March: Comb out dead leaves, cut off old flower stems.
• April: New growth. Scatter a thin layer of fresh sand in the garden.
• June: Flowering starts with pale spikes.
• July: Full flower.
• August: Seed ripens.
• November: Plant or divide in moist sand.
• December: Winter silhouette; holds the sand during storms.

Did you know?

• Ammophila means ‘sand-loving’ in Greek: ammos is sand, philos is friend.
• In dry weather the leaf rolls up into a tube. The breathing pores are on the inside, so the plant loses less water.
• Marram grows upwards when it is buried: a tussock can keep pace, year after year, with a dune that keeps getting higher.