Gray's sedge

Carex grayi

In other languages: Carex grayi (Nederlands) · Carex grayi (Français)

Carex grayi, known as Gray’s sedge, is a sedge from eastern North America, where it grows in wet meadows, swampy woods and along rivers. It forms a sturdy clump 60–90 cm tall with fresh green, fairly broad leaves. Its special feature is the fruit: from summer on, spiky green balls about 3 cm across appear on the stems, looking like a medieval mace or morning star. They turn brown later and are excellent in dried arrangements and as cut flowers. The plant is fully hardy and happiest on a moist to wet spot, for example at the edge of a pond.

Updated on 9 October 2026

Light
Sun or partial shade
preferably some sun
Moisture
Normal to wet
must not dry out
Legal basis
Loam, clay or peat
any pH
Hardiness
Fully hardy
down to -30 °C
Size
0.7 m
tall, 0.5 m wide
Flowering
June–August

Key facts
Pruning months	March
Height	0.7 m
Native to Belgium	No, planted
Poisonous to people and pets	Not known to be poisonous
Flowering	June–August

Identify

Gray's sedge: how do you recognise it?

Habit: Sturdy, upright clump 60–90 cm tall and 40–50 cm wide.
Leaves: Narrow ribbon-like, up to about 1 cm wide, fresh green, yellow-brown in autumn.
Flower: Inconspicuous spikes in June–July on upright stems; the female flowers sit in a rounded spike.
Fruit: Green balls about 3 cm across full of spiny fruits, turning brown later; the main ornamental feature.
Stem: Fairly stout and triangular, as in many sedges.

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

In your garden

Why grow it?

Striking, spiky fruiting balls that no other sedge has.
Lovely as a cut flower and dried in everlasting bouquets, lasting a long time.
Fully hardy and low maintenance: one cut a year.
Great for wet, awkward spots, pond edges and banks.
Fresh green foliage that contrasts well with flowering moisture lovers.

Gray's sedge: where does it grow best?

Sun or half shade; in sun the soil should preferably stay moist.
Moist to wet, fertile soil: loam, clay or peat, acid to chalky.
Even tolerates wet feet for a while or shallow water at the pond edge.
Shelter it from strong wind. Allow 40–50 cm between plants.

Light: Sun and partial shade
Soil type: Loam, clay or peat
Acidity: Not fussy
Moisture: Normal or wet
Size: 0.7 m tall, 0.5 m wide
Hardiness: Hardy (to -30 °C)

Goes well with

Yellow flag iris: Sturdy marginal plant with yellow flowers in spring.
Meadowsweet: Creamy-white plumes on the same moist soil.
Rodgersia: Large, decorative leaves in moist half shade.
Marsh marigold: Yellow flowers in early spring at wet edges.

Maintenance

Gray's sedge: when and how to plant it?

Plant in March–May and September–October.

Plant in March–May or in September–October, when the soil is not frozen.
Dig a hole twice as wide as the root ball and mix in a few spades of compost.
Set the plant at the same depth as in its pot and firm the soil well.
Plant in groups of 3–5, 40–50 cm apart.
Water thoroughly straight away, even if it rains.
Spread a layer of leaf-mould mulch around the clump to hold the moisture.

Care

Water: Keep the soil moist at all times; in dry summers water generously and regularly.
Feeding: A spade of compost in spring; no more is needed.
Mulching: A layer of leaf mould in spring keeps the soil wet and cool.
Fruit heads: Cut them when the balls are fully grown but still green, for a fresh or dried arrangement.
Dividing: If the heart of the clump is bare, divide it in spring after 3–4 years.

Tip: Cut the balls while they are still green and firm and hang them upside down to dry: they keep their shape into winter.

Gray's sedge: when to prune it?

Pruning months: March.

When: From late February to March, before the new shoots start to grow.

How:

Cut the old brown leaves and stems back to about 5–10 cm above the ground.
Use sharp secateurs or shears and wear gloves.
Pull dead leaves from between the new shoots with your fingers.
In summer you can cut fruit heads for a bouquet.

Caution: Do not cut into the new shoots, only the old foliage.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division: In March–April lift the clump and divide it with a sharp spade into pieces with roots and shoots; replant straight away and water.
Seed: Sow in spring on moist soil, or collect the ripe fruits; the seed germinates slowly and unevenly.

Gray's sedge: how does it get through the winter?

Hardy to −30 °C.

Fully hardy, to about −30 °C: no protection needed.
The foliage changes colour in autumn and dies back in winter; the clump shoots again in spring.
In a pot: keep the compost moist, place the pot against a wall and protect it with hessian in severe frost.

Diseases and pests

Brown leaf tips: The soil is too dry. Water generously, mulch and preferably choose a damper spot.
Floppy, flattened stems: Too much shade or after heavy rain. Move the plant to a lighter spot and plant in groups so the clumps support one another.
Bare heart: After a few years. Divide the clump in spring and replant the young pieces.
Self-sown seedlings: In wet soil young plants may establish. Weed them out or move them in spring.

Through the year

March: Cut back old foliage. Divide and plant. Add compost.
April: Plant. Mulch.
May: Plant. Water in dry spells.
June: Inconspicuous spikes flower.
July: Fruit heads form. Water in dry spells.
August: Cut fruit heads for bouquets.
September: Plant. Make dried bouquets.
October: Plant. Yellow-brown autumn colour.
December: Rest. Leave the brown clump standing.

You and this species

Did you know?

The plant is named after the American botanist Asa Gray.
It is also called mace sedge or morning star sedge, after the spiky fruiting balls.
In the wild it grows in wet places such as river banks and wet woods in eastern North America.

Garden plants · All species