Western blue-eyed grass

Sun

Full sun to light partial shade; give it some afternoon shade in hot inland gardens.

Water

Moderate moisture during active growth in autumn through spring; little summer water is needed once established in mild, dry-summer climates.

Soil

Well-drained sandy, loamy or clay soil; tolerates heavier soil provided it does not remain waterlogged.

Height

1-2 ft (0.3-0.6 m)

Spread

0.5-1 ft (0.15-0.3 m)

Flowers

Spring to early summer; violet-blue to purple flowers with yellow centres, opening most freely in sunshine.

Foliage

Narrow, flat, green leaves form upright to arching tufts. Often evergreen in mild, moist conditions, but foliage can die back during summer drought or cold winters.

Growth

Moderate; forms small clumps and may self-seed.

Care needed

Low

• Pollinators
• Deer resistant
• Drought tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.1 ft (0.35 m)

3. After 2 years

   1.3 ft (0.4 m)

4. After 3 years

   1.5 ft (0.45 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Native to

the US

Growth rate

Moderate

• Water new plants regularly during their first growing season, allowing the surface soil to dry between waterings.
• Keep the soil moderately moist while plants are growing and flowering; reduce watering during summer dormancy.
• Avoid rich feeding; use only a light spring dressing of compost on poor soil.
• Keep mulch away from the crown, especially in wet climates.
• Divide crowded clumps in spring or autumn when the soil is moist and temperatures are mild.

Pruning. Remove spent flower stems before seed capsules ripen if you want to limit seedlings. Cut away dead leaves after summer dormancy or winter damage, leaving green growth intact.

Early spring

Remove dead foliage and divide crowded clumps as active growth begins.

Spring

Plant in colder or wetter regions once the soil is workable; water thoroughly after planting.

Spring to early summer

Water during prolonged dry spells while plants are flowering.

Early summer

Remove fading flower stems to prevent self-seeding, or leave a few capsules to collect ripe seed.

Summer

Reduce watering if foliage dies back naturally; do not keep dormant crowns constantly wet.

Autumn

Plant or divide in mild, dry-summer regions after rain returns, and remove unwanted seedlings.

• Plant in loose drifts through a low meadow with fine-textured grasses for a light scattering of spring colour.
• Use along sunny path edges, where the small flowers can be seen close up.
• Combine with California poppies and yarrow in a seasonally dry, western native planting.
• Tuck small groups into an informal gravel garden, allowing room for occasional seedlings.

Garden styles it suits: California native, Native meadow, Wildflower, Pollinator garden, Dry gravel garden and Mediterranean.

Plant it with: California poppy, Yarrow, Purple needlegrass, Blue grama, Douglas iris and California fuchsia.

Wildlife: The flowers provide pollen for small native bees and other visiting insects. Leaving some seed heads allows natural regeneration, though this also increases seedlings.

• Crown or root rot in persistently wet soil: improve drainage and avoid burying the crown or watering dormant plants heavily.
• Slugs and snails eating young growth: remove hiding places and use barriers or a labelled iron-phosphate bait where needed.
• Unwanted seedlings: cut off flower stems before capsules ripen and pull seedlings while small.
• Brown foliage in summer drought: this can be normal dormancy; remove dead leaves and avoid trying to force growth with constant watering.

Not known to be toxic to people, cats, dogs or horses, but species-specific safety information is limited. No part is a recognised food; discourage pets and children from eating the leaves, flowers, roots or seeds.

• Narrow-leaved blue-eyed grass (Sisyrinchium angustifolium)

  Its flowers are very similar, but it usually has conspicuously flattened, winged flowering stems and commonly branched flower clusters. Identification from flowers alone is unreliable.

• Annual blue-eyed grass (Sisyrinchium rosulatum)

  Usually a smaller, short-lived plant with tiny pale lilac, pinkish or whitish flowers, often marked by a darker ring around the yellow centre.

• Yellow-eyed grass (Sisyrinchium californicum)

  Has clear yellow flowers rather than violet-blue flowers and generally prefers wetter ground.

The species name bellum means 'beautiful' in Latin, while 'blue-eyed grass' describes the blue flowers held above grass-like leaves.

Propagation. Divide established clumps in spring or autumn, keeping roots attached to each division. Sow ripe seed in a well-drained seed mix in autumn and leave outdoors in a sheltered position; germination can be uneven, and seedlings may differ from named garden selections.

Accepted botanical name

Sisyrinchium bellum

In the US and Canada

Native in the lower 48 states.

Native range

California, Mexico Northwest and Oregon.

Measured

Average height 16 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.