Blue Flax Lily Plant Care
Dianella caerulea var. caerulea
Updated · Sources · How we source care data
Dianella caerulea, commonly known as the blue flax-lily, blueberry lily, or paroo lily, is a perennial herb of the family Asphodelaceae, subfamily Hemerocallidoideae, found across the eastern states of Australia and Tasmania. It is a hardy plant, growing to a height and width of around 1 metre with grass-like strappy leaves.
Every 7–10 days
Partial shade to full sun
50–85°F
40–70%
At a glance
How do you care for Blue Flax Lily?
Water Blue Flax Lily every 7–10 days, letting the top layer of soil dry out between waterings, and give it partial shade to full sun. It prefers temperatures of 50–85°F (10–29°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Blue Flax Lily?
Blue Flax Lily (Dianella caerulea var. caerulea) belongs to the Asphodelaceae family within the Dianella genus. Blue Flax Lily is also known as Blueberry Lily, Flax Lily.
Blue Flax Lily displays a clumping perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Blue Flax Lily produces small blue or white flowers in clusters.
Leaf size: approximately 18 inches.
How Often Should You Water a Blue Flax Lily?
Dianella caerulea var. caerulea 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 Blue Flax Lily Need?
Blue Flax Lily thrives in partial shade to full sun.
Light Requirement
Partial shade to full sun
What Temperature and Humidity Does the Blue Flax Lily Prefer?
Dianella caerulea var. caerulea grows best at temperatures of 50–85°F. Blue Flax Lily prefers humidity levels of 40–70%.
Temperature
50–85°F
Humidity
40–70%
What Soil Mix Works Best for a Blue Flax Lily?
Well-draining sandy loam with added organic matter. Good drainage is essential for Blue Flax Lily to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Blue Flax Lily?
Feed Blue Flax Lily 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 Blue Flax Lily?
Repot every 2-3 years in 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 Blue Flax Lily?
Blue Flax Lily can be propagated through division, seeds. Similar propagation techniques also apply to blueberry lily plant care, which shares the same genus.
Is the Blue Flax Lily Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Blue Flax Lily, 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 Blue Flax Lily?
Blue Flax Lily is susceptible to aphids, scale insects, spider mites. 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 Blue Flax Lily Need?
Blue Flax Lily grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Blue Flax Lily as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Blue Flax Lily 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 Dianella genus — compare its care with other Dianella species on PlantoScan.
Dianella is part of the Asphodelaceae plant family — browse all Asphodelaceae genera and species.
Blue Flax Lily thrives in bright light and direct sun — see other bright-light plants.
More Dianella Species
Other Dianella species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Dianella caerulea var. caerulea, family Asphodelaceae (first published in Queensland Department of Agriculture and Stock Bulletin 9. Botany Bulletin 3 1891) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Blue Flax Lily, 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.
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