Giant sow thistle Plant Care
Sonchus regius (Skottsb.) S.C.Kim & Mejías
Updated · Sources · How we source care data
With its striking silver-grey leaves covered in fine hairs, this plant originates from the Canary Islands. Plant collectors are drawn to Sonchus regius for its unique foliage that adds a touch of exotic beauty to any garden or collection.
Every 4–7 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Giant sow thistle?
Water Giant sow thistle every 4–7 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 Giant sow thistle Native To?
What Is the Giant sow thistle?
Giant sow thistle (Sonchus regius) belongs to the Asteraceae family within the Sonchus genus. Giant sow thistle is native to the Juan Fernández Islands of Chile. Giant sow thistle is also known as Giant Fleabane, Tree Sow Thistle.
Giant sow thistle displays an upright, branching herbaceous plant growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Giant sow thistle produces small yellow daisy-like flowers in clusters.
Leaf size: approximately 6 inches.
How Often Should You Water a Giant sow thistle?
Sonchus regius requires watering every 4–7 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 4–7 days
Let soil partially dry between waterings
What Light Does the Giant sow thistle Need?
Giant sow thistle thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Giant sow thistle Prefer?
Sonchus regius grows best at temperatures of 50–80°F. Giant sow thistle prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Giant sow thistle?
Well-draining, fertile soil with added compost or organic matter. Good drainage is essential for Giant sow thistle to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Giant sow thistle?
Feed Giant sow thistle 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 Giant sow thistle?
Repot every 1-2 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 Giant sow thistle?
Giant sow thistle can be propagated through seeds, division of root ball. Similar propagation techniques also apply to species plantarum plant care, which shares the same genus.
Is the Giant sow thistle Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Giant sow thistle, 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 Giant sow thistle?
Giant sow thistle is susceptible to aphids, caterpillars, slugs. 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 Giant sow thistle Need?
Giant sow thistle grows outdoors in USDA Zone 9b – 11b. It survives winters down to planting zone 9b. Giant sow thistle is native to the Juan Fernández Islands of Chile. In cooler regions, grow Giant sow thistle as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 9b – 11b
Keep exploring plants
Giant sow thistle 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 Sonchus genus — compare its care with other Sonchus species on PlantoScan.
Sonchus is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Giant sow thistle thrives in bright light and direct sun — see other bright-light plants.
More Sonchus Species
Other Sonchus species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Sonchus regius (Skottsb.) S.C.Kim & Mejías, family Asteraceae (first published in Ann. Bot. Fenn. 49(3): 176 (2012)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Giant sow thistle, 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 9b – 11b, estimated from the plant's typical growing conditions.
- 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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