Does it need pruning?

Yes, cut the dead foliage back to the ground in late winter or early spring.

Can it grow in shade?

It prefers full sun but tolerates light shade.

Plant guide

Purple moor grass.

Molinia caerulea

Pronounced mo-LIN-ee-uh see-ROO-lee-uh

Also known as Purple Moor-Grass, Purple moorgrass

Purple moor grass is a lovely, clump forming perennial that adds a soft, airy texture to your garden. It produces graceful, arching stems topped with delicate purple tinted flower spikes in late summer. This grass is a fantastic choice for adding movement and a natural feel to your landscape.

At a glance

Care level: Easy
Plant type: Perennial grass
Light: Full sun to partial shade
Indoor light: Bright indirect
Water: Every 3 to 7 days
Mature size: 2 to 3 feet
Growth rate: Medium
Hardiness: USDA 4 to 9
Bloom time: Mid to late summer

Care

Plant this grass in moist, acidic soil to keep it happy throughout the growing season. Watch for browning leaf tips, which often signal that the soil has become too dry. You should cut the foliage back to the ground in late winter before new growth appears.

Watering: Keep the soil consistently moist but never waterlogged.
Feeding: Apply a balanced, slow release fertilizer once in early spring.
Pruning: Cut back all foliage to the ground in late winter.
Repotting: Divide the clumps every few years to keep the plant vigorous.
Soil: Moist, acidic, well draining soil
Soil pH: Acidic
Temperature: -34 to 30°C
Humidity: 40 to 70%

Safety

People: There is no known toxicity to humans.
Children: The sharp leaf blades can cause paper cut style scratches on delicate skin.
Contact allergens: The leaf edges can be sharp and may cause minor skin abrasions.
Airborne allergens: The pollen can cause seasonal hay fever in sensitive individuals.
Edibility: This grass is not considered edible for humans.

How to identify it

Clump forming habit
Narrow, arching green leaves
Purple tinted flower panicles
Straw colored fall foliage

Height: 0.4 to 1.2m
Spread: 0.3 to 0.6m
Leaves: green, yellow, deciduous
Flowers: purple, brown, 0.5 to 1cm
Fruit: brown, Autumn

Problems to watch for

RustCommon
DehydrationUncommon
Leaf SpotUncommon
Root RotUncommon

By symptom

Plant problems by symptom

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Growing it

Propagation: division, seed
When to plant: Spring, Autumn

Group with other moisture loving plants to create a cohesive bog or meadow garden.

Grows well with

Heather · They share similar requirements for acidic, moist soil.
Joe Pye Weed · The tall, bold flowers contrast nicely with the fine texture of the grass.

Similar species

Tufted Hair Grass · It shares a similar clumping habit and preference for cool, moist conditions.

Science

Family: Poaceae
Genus: Molinia
Order: Poales
Class: Liliopsida
Native range: Europe and parts of Asia.
Conservation: It is widespread and not of conservation concern.

It naturally inhabits damp heaths, moors, and meadows where it tolerates acidic conditions.

Value to wildlife: larval host plant, nesting material
Pollinators: bees, butterflies
Uses: ornamental grass, prairie planting, container plant

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 1/9
Soil reaction: 3/9
Light: 7/9
Temperature: 5/9
Moisture: 7/9
Nutrients: 3/9

Taxonomy resolved against GBIF.

Questions people ask

Does it need pruning?: Yes, cut the dead foliage back to the ground in late winter or early spring.
Can it grow in shade?: It prefers full sun but tolerates light shade.

Where the name comes from

The genus honors the Chilean botanist Juan Ignacio Molina, while the species name refers to the bluish tint of the flowers.

Good to know

It is commonly known as purple moor grass.
It thrives in acidic, damp soils where other grasses struggle.
The flower spikes rise well above the foliage mound.

Keep your purple moor grass growing

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This guide was generated with AI on September 26, 2026 and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.