Photo: Walter SiegmundCC BY 2.5via Wikimedia Commonsresized / cropped
Large aster Plant Care
Aster major (Hook.) Porter
Updated · Sources · How we source care data
Canadanthus is a North American genus of flowering plants in the family Asteraceae. The only known species is Canadanthus modestus (formerly Aster modestus), native to most of Canada (Alberta, British Columbia, Manitoba, Ontario, New Brunswick, Quebec, Saskatchewan, and Yukon) and to northern parts of the United States (Alaska, Idaho, Michigan, Minnesota, Montana, North Dakota, Oregon, South Dakota, Washington state, and Wisconsin).
Every 7–10 days
Full sun to partial shade
50–75°F
40–70%
At a glance
How do you care for Large aster?
Water Large aster 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 50–75°F (10–24°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
Where Is the Large aster Native To?
What Is the Large aster?
Large aster (Aster major) belongs to the Asteraceae family within the Aster genus. Large aster is native to most of Canada and to northern parts of the United States. Large aster is also known as Aster modestus.
Large aster displays an upright, bushy perennial growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Large aster produces daisy-like flowers in various colors like purple, pink, white, and blue.
Leaf size: approximately 4 inches.
How Often Should You Water a Large aster?
Aster major 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 Large aster Need?
Large aster thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Large aster Prefer?
Aster major grows best at temperatures of 50–75°F. Large aster prefers humidity levels of 40–70%.
Temperature
50–75°F
Humidity
40–70%
What Soil Mix Works Best for a Large aster?
Well-draining loamy soil with added compost for nutrients. Good drainage is essential for Large aster to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Large aster?
Feed Large aster 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 Large aster?
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 Large aster?
Large aster can be propagated through seeds, division of clumps. Similar propagation techniques also apply to rough-surface aster plant care, which shares the same genus.
Is the Large aster Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Large aster, 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 Large aster?
Large aster is susceptible to aphids, slugs, snails. 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 Large aster Need?
Large aster grows outdoors in USDA Zone 2a – 7b. It survives winters down to planting zone 2a. Large aster is native to most of Canada and to northern parts of the United States.
Hardiness Zone
Zone 2a – 7b
Keep exploring plants
Large aster 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 Aster genus — compare its care with other Aster species on PlantoScan.
Aster is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Large aster thrives in bright light and direct sun — see other bright-light plants.
More Aster Species
Other Aster species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Aster major (Hook.) Porter, family Asteraceae (first published in Mem. Torrey Bot. Club 5: 325 (1894)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Large aster, 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.
- Photo: Walter Siegmund, CC BY 2.5, Wikimedia Commons — original.
- Hardiness zone: USDA Zone 2a – 7b, 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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