Roan Mountain Blue Eyed Grass Plant Care

Sisyrinchium sarmentosum Suksd. ex Greene

Updated · Sources · How we source care data

Sisyrinchium sarmentosum is a species of flowering plant in the iris family known by the common names mountain blue-eyed grass and pale blue-eyed-grass. It is native to the Pacific Northwest of North America, where it is known from a part of the Cascade Mountains in Washington and Oregon.

🌼Perennials🧅Bulbs & Tubers
Water

Every 7–10 days

Light

Full sun to partial shade

Temp

50–80°F

Humidity

40–70%

At a glance

How do you care for Roan Mountain Blue Eyed Grass?

Water Roan Mountain Blue Eyed Grass every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 50–80°F (10–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.

Where Is the Roan Mountain Blue Eyed Grass Native To?

Native range3 countries

What Is the Roan Mountain Blue Eyed Grass?

Roan Mountain Blue Eyed Grass (Sisyrinchium sarmentosum) belongs to the Iridaceae family within the Sisyrinchium genus. Roan Mountain Blue Eyed Grass is native to the Pacific Northwest of North America.

Roan Mountain Blue Eyed Grass displays a clumping perennial growth habit, reaching up to 1 ft tall with a spread of approximately 1 ft. Roan Mountain Blue Eyed Grass produces small, star-shaped flowers in shades of blue, purple, or yellow.

Leaf size: approximately 6 inches.

How Often Should You Water a Roan Mountain Blue Eyed Grass?

Sisyrinchium sarmentosum requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.

Watering Frequency

Every 7–10 days

Let soil partially dry between waterings

What Light Does the Roan Mountain Blue Eyed Grass Need?

Roan Mountain Blue Eyed Grass thrives in full sun to partial shade.

Light Requirement

Full sun to partial shade

What Temperature and Humidity Does the Roan Mountain Blue Eyed Grass Prefer?

Sisyrinchium sarmentosum grows best at temperatures of 50–80°F. Roan Mountain Blue Eyed Grass prefers humidity levels of 40–70%.

Temperature

50–80°F

Humidity

40–70%

What Soil Mix Works Best for a Roan Mountain Blue Eyed Grass?

Well-draining sandy loam with added organic matter. Good drainage is essential for Roan Mountain Blue Eyed Grass to prevent waterlogging, which leads to root rot and fungal issues.

How Often Should You Fertilize a Roan Mountain Blue Eyed Grass?

Feed Roan Mountain Blue Eyed Grass every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.

Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.

Fertilizing

Every 6 months

During the growing season

The PlantoScan app can remind you when to water and when to fertilize each plant.

How Do You Repot a Roan Mountain Blue Eyed Grass?

Divide and repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.

How Do You Propagate a Roan Mountain Blue Eyed Grass?

Roan Mountain Blue Eyed Grass can be propagated through division of rhizomes, seeds. Similar propagation techniques also apply to bermuda blue-eyed grass plant care, which shares the same genus.

Is the Roan Mountain Blue Eyed Grass Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Roan Mountain Blue Eyed Grass, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.

This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.

See all plants toxic to cats and plants toxic to dogs.

What Pests and Diseases Affect the Roan Mountain Blue Eyed Grass?

Roan Mountain Blue Eyed Grass is susceptible to aphids, spider mites, thrips. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

What USDA Hardiness Zone Does the Roan Mountain Blue Eyed Grass Need?

Roan Mountain Blue Eyed Grass grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Roan Mountain Blue Eyed Grass is native to the Pacific Northwest of North America. In cooler regions, grow Roan Mountain Blue Eyed Grass as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 12a

Keep exploring plants

Roan Mountain Blue Eyed Grass is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.

It belongs to the Sisyrinchium genus — compare its care with other Sisyrinchium species on PlantoScan.

Sisyrinchium is part of the Iridaceae plant family — browse all Iridaceae genera and species.

Roan Mountain Blue Eyed Grass thrives in bright light and direct sun — see other bright-light plants.

More Sisyrinchium Species

Other Sisyrinchium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:

Sources

  • Scientific name & taxonomy: Sisyrinchium sarmentosum Suksd. ex Greene, family Iridaceae (first published in Erythea iii. (1895) 121.) — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Roan Mountain Blue Eyed Grass, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
  • Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
  • Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.

Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.

PlantoScan app icon

Identify Plants Like the
Roan Mountain Blue Eyed Grass Instantly

Scan any plant with your phone camera and get instant ID, care tips, water and fertilizer reminders, and health checks — all in one app.

Download on the App StoreGet it on Google Play

Free

to download

iOS & Android

platforms

Light & dark

mode

100,000+

species