Photo: Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York. Vol. 3: 458. Courtesy of Kentucky Native Plant Society. Scanned by Omnitek Inc.Public domainvia Wikimedia Commons
Canadian Polymnia Plant Care
Polymnia canadensis L.
Updated · Sources · How we source care data
Polymnia canadensis, commonly known as whiteflower leafcup, is a flowering plant native to eastern North America from Ontario south to Alabama and from Kansas, Oklahoma, and Minnesota east to North Carolina, Vermont and Connecticut. It is considered endangered in the last two states. It is typically found in moist forests over calcareous rocks.
Every 5–7 days
Full sun to partial shade
60–75°F
40–60%
At a glance
How do you care for Canadian Polymnia?
Water Canadian Polymnia every 5–7 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 60–75°F (16–24°C) and 40–60% humidity. Fertilize it every 6 months during the growing season.
Where Is the Canadian Polymnia Native To?
What Is the Canadian Polymnia?
Canadian Polymnia (Polymnia canadensis) belongs to the Asteraceae family within the Polymnia genus. Canadian Polymnia is native to eastern North America from Ontario south to Alabama and from Kansas, Oklahoma, and Minnesota east to North Carolina, Vermont and Connecticut. Canadian Polymnia is also known as Leafcup, Polymnia canadensis, Polymnia radiata.
Canadian Polymnia displays a clumping perennial herb growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Canadian Polymnia produces small yellow composite flowers in dense clusters.
Leaf size: approximately 6 inches.
How Often Should You Water a Canadian Polymnia?
Polymnia canadensis requires watering every 5–7 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 5–7 days
Let soil partially dry between waterings
What Light Does the Canadian Polymnia Need?
Canadian Polymnia thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Canadian Polymnia Prefer?
Polymnia canadensis grows best at temperatures of 60–75°F. Canadian Polymnia prefers humidity levels of 40–60%.
Temperature
60–75°F
Humidity
40–60%
What Soil Mix Works Best for a Canadian Polymnia?
Well-draining loamy soil with added compost for nutrients. Good drainage is essential for Canadian Polymnia to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Canadian Polymnia?
Feed Canadian Polymnia 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 Canadian Polymnia?
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 Canadian Polymnia?
Canadian Polymnia can be propagated through seeds, division of rhizomes. Similar propagation techniques also apply to polymnia johnbeckii plant care, which shares the same genus.
Is the Canadian Polymnia Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Canadian Polymnia, 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 Canadian Polymnia?
Canadian Polymnia is susceptible to aphids, spider mites, whiteflies. 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 Canadian Polymnia Need?
Canadian Polymnia grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Canadian Polymnia is native to eastern North America from Ontario south to Alabama and from Kansas, Oklahoma, and Minnesota east to North Carolina, Vermont and Connecticut. In cooler regions, grow Canadian Polymnia as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Canadian Polymnia 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 Polymnia genus — compare its care with other Polymnia species on PlantoScan.
Polymnia is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Canadian Polymnia thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Polymnia canadensis L., family Asteraceae (first published in Sp. Pl. : 926 (1753)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Canadian Polymnia, 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: Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York. Vol. 3: 458. Courtesy of Kentucky Native Plant Society. Scanned by Omnitek Inc., Public domain, Wikimedia Commons — original.
- 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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