Indian grass

Indian grass: how do you recognise it?

Habit

Stiff, upright clump about 1.5 m tall and 60 cm wide, slowly spreading.

Foliage

Narrow, long and blue-green to blue-grey; strongly blue in ‘Sioux Blue’. Yellow to golden orange in autumn.

Plumes

Narrow plumes 20–30 cm long, golden brown with yellow stamens, from August to September.

Seeds

The seeds ripen in autumn and are eaten by birds.

Roots

Deep and fibrous, with short rhizomes: the clump stands firmly and gets through dry spells.

Flowering: August–September · Plants: April–May · Pruning: March

Why grow it?

• Blue-grey foliage and golden-brown plumes with yellow stamens: a stunning late-summer pairing.
• Straight, stiff clumps that give height and structure to a border, even in a narrow garden.
• Tolerates drought and heavy clay, even on poor soil.
• The seeds feed birds in autumn and winter.
• Low maintenance: one cut a year, no feeding needed.

Indian grass: where does it grow best?

• Full sun: in shade the clump flops and flowers less.
• Almost any soil: sand, loam or clay, acid to chalky. On poor soil it stays firmly upright.
• Dry to moderately moist: once established it copes with drought.
• In a sheltered or open spot: the stiff stems stand firmly, but strong autumn wind can bend them.
• Allow 50–60 cm between plants.

Light

Sun

Soil type

Sand, loam or clay

Acidity

Not fussy

Moisture

Dry or normal

Size

1.5 m tall, 0.6 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Coneflower (Echinacea): Pink flowers on sturdy stems, flowering in the same sunny summer.
• Rudbeckia: Yellow flowers in late summer: a lovely contrast with the blue foliage.
• Aster: Purple or pink stars in September–October, when the grass is at its best.
• Stonecrop (Sedum): Lower plants with pink late-summer flowers, at the foot of the tall clumps.
• Yarrow (Achillea): Flat heads in yellow or pink, in the same dry sun.

Indian grass: when and how to plant it?

Plant in April–May.

1. Plant in April or May, once the soil has warmed up: this warm-season grass establishes best then.
2. Dig a hole twice as wide as the root ball. On heavy clay you can mix in some coarse sand.
3. Set the plant at the same depth as in its pot and firm the soil well.
4. Leave 50–60 cm between plants.
5. Water in thoroughly straight away, then weekly in dry weather during the first year.
6. Spread a thin layer of compost or fine wood chip around the plant, keeping it clear of the base.

Care

Water

Weekly in dry weather in the first year, after that only in long droughts.

Feeding

Not needed: on poor soil it grows firm and upright. Too much feed gives soft stems.

Spring growth

It starts late, often not until May. That is normal, so do not clear the clump too early.

Support

Usually not needed. If it flops open, it is in too much shade or soil that is too rich.

Dividing

If the clump gets too big or bare in the centre, divide it in May–June.

Tip: Keep the clumps until March: the golden-brown plumes decorate the garden well into winter and the seeds feed birds. Cut back only when the new shoots are about to start.

Indian grass: when to prune it?

Pruning months: March.

When: In March, just before the new shoots start to grow.

How:

• Cut all stems and leaves back to about 10–15 cm above the ground.
• Tie the clump together with string first: this makes clearing up easy.
• Wear gloves, as the leaf edges of grasses can be sharp.
• The cuttings can go on the compost heap.

Caution: Do not cut in autumn: the seed plumes feed birds over winter and the clump protects its heart from wet and frost.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In May–June, when growth gets going: split a clump with a sharp spade into pieces, each with roots and shoots, and replant straight away. The clump is tough, so use a sturdy spade.

Seed

Sow in spring on seed compost, barely cover and keep lightly moist. Seedlings may differ from a selection such as ‘Sioux Blue’: division is more reliable.

Indian grass: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy, to about −30 °C: no protection is needed in Belgium.
• Leave the clumps and seed plumes standing until March: they look good and feed birds.
• In a pot: use a large pot of at least 40 cm, stand it against a sheltered wall and wrap it in hessian in severe frost.

Diseases and pests

• Flopping clump: Caused by shade or soil that is too rich. Move to full sun, do not feed, and divide the clump.
• No growth in April: The plant is not dead: warm-season grasses do not start until May. Be patient.
• Rotting in winter: On cold, wet clay the clump can rot away. Mix coarse sand into the soil or plant on a mound.
• Leaf spot and rust: Brown or orange spots after long damp spells. Usually harmless: leave space between plants and cut off affected leaves in March.

Through the year

• March: Cut all clumps back to 10–15 cm.
• April: Plant. Nothing to see yet: the grass starts late.
• May: Plant or divide. First shoots appear.
• June: Strong growth. In the first year water weekly in dry weather.
• July: The blue foliage is at its best.
• August: Flowering begins, with golden-brown plumes.
• September: Full plumes with yellow stamens. The foliage turns yellow.
• October: Autumn colour. Seeds for the birds.
• November: Leave the clumps standing: they decorate the garden.
• December: Resting. The straw-coloured clumps give winter structure.

Good for wildlife

Birds

Berries, seeds or insects as food, or a place to nest.

Did you know?

• Together with other tall grasses, Indian grass formed the great tallgrass prairies of North America.
• The species name nutans means ‘nodding’ in Latin, referring to the gently bowing plumes.
• Indian grass is the official state grass of the US state of Oklahoma.