Blue Devil Plant Care
Eryngium ovinum A.Cunn.
Updated · Sources · How we source care data
Eryngium ovinum, commonly known as the blue devil, is a plant species native to Australia.
Every 7–14 days
Full sun to partial shade
60–80°F
40–70%
At a glance
How do you care for Blue Devil?
Water Blue Devil every 7–14 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 60–80°F (16–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
Where Is the Blue Devil Native To?
What Is the Blue Devil?
Blue Devil (Eryngium ovinum) belongs to the Apiaceae family within the Eryngium genus. Blue Devil is native to Australia. Blue Devil is also known as Fringed Eryngo.
Blue Devil displays an upright, clumping perennial growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Blue Devil produces small, cone-shaped blue or white flowers surrounded by spiky bracts.
Leaf size: approximately 6 inches.
How Often Should You Water a Blue Devil?
Eryngium ovinum requires watering every 7–14 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 7–14 days
Let soil partially dry between waterings
What Light Does the Blue Devil Need?
Blue Devil thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Blue Devil Prefer?
Eryngium ovinum grows best at temperatures of 60–80°F. Blue Devil prefers humidity levels of 40–70%.
Temperature
60–80°F
Humidity
40–70%
What Soil Mix Works Best for a Blue Devil?
Well-draining sandy soil with good organic content. Good drainage is essential for Blue Devil to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Blue Devil?
Feed Blue Devil 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 Devil?
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 Blue Devil?
Blue Devil can be propagated through seeds, division of offsets. Similar propagation techniques also apply to alligator weed plant care, which shares the same genus.
Is the Blue Devil Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Blue Devil, 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 Devil?
Blue Devil is susceptible to aphids, spider mites, powdery mildew. 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 Devil Need?
Blue Devil grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Blue Devil is native to Australia. In cooler regions, grow Blue Devil as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Blue Devil 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 Eryngium genus — compare its care with other Eryngium species on PlantoScan.
Eryngium is part of the Apiaceae plant family — browse all Apiaceae genera and species.
Blue Devil thrives in bright light and direct sun — see other bright-light plants.
More Eryngium Species
Other Eryngium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Eryngium ovinum A.Cunn., family Apiaceae (first published in Geogr. Mem. New South Wales : 358 (1825)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Blue Devil, 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 13a, 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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