Glandular Fireweed Plant Care
Epilobium glandulosum Lehm.
Updated · Sources · How we source care data
Epilobium ciliatum, known by the common names fringed willowherb, American willowherb, slender willow herb, and northern willow herb is a species of flowering plant in the willowherb family Onagraceae. This species is native to much of North America, southern South America, and East Asia.
Every 3–5 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Glandular Fireweed?
Water Glandular Fireweed every 3–5 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 Glandular Fireweed Native To?
What Is the Glandular Fireweed?
Glandular Fireweed (Epilobium glandulosum) belongs to the Onagraceae family within the Epilobium genus. Glandular Fireweed is native to much of North America, southern South America, and East Asia. Glandular Fireweed is also known as Glandular Willowherb, Northern Willowherb.
Glandular Fireweed displays an upright, spreading perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Glandular Fireweed produces showy spikes of pink, purple, or white flowers.
Leaf size: approximately 4 inches.
How Often Should You Water a Glandular Fireweed?
Epilobium glandulosum requires watering every 3–5 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 3–5 days
Let soil partially dry between waterings
What Light Does the Glandular Fireweed Need?
Glandular Fireweed thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Glandular Fireweed Prefer?
Epilobium glandulosum grows best at temperatures of 50–80°F. Glandular Fireweed prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Glandular Fireweed?
Moist, well-draining soil rich in organic matter. Good drainage is essential for Glandular Fireweed to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Glandular Fireweed?
Feed Glandular Fireweed 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 Glandular Fireweed?
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 Glandular Fireweed?
Glandular Fireweed can be propagated through seeds, division. Similar propagation techniques also apply to american willowherb plant care, which shares the same genus.
Is the Glandular Fireweed Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Glandular Fireweed, 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 Glandular Fireweed?
Glandular Fireweed is susceptible to aphids, caterpillars, leaf miners. 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 Glandular Fireweed Need?
Glandular Fireweed grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Glandular Fireweed is native to much of North America, southern South America, and East Asia. In cooler regions, grow Glandular Fireweed as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Glandular Fireweed 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 Epilobium genus — compare its care with other Epilobium species on PlantoScan.
Epilobium is part of the Onagraceae plant family — browse all Onagraceae genera and species.
Glandular Fireweed thrives in bright light and direct sun — see other bright-light plants.
More Epilobium Species
Other Epilobium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Epilobium glandulosum Lehm., family Onagraceae (first published in Fl. Bor.-Amer. (Hooker) 1(4): 206. 1832) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Glandular Fireweed, 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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