Hairy Willowherb Plant Care
Epilobium collinum C.C.Gmel.
Updated · Sources · How we source care data
Epilobium collinum is a species of flowering plant belonging to the family Onagraceae.
Every 3–5 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Hairy Willowherb?
Water Hairy Willowherb 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.
What Is the Hairy Willowherb?
Hairy Willowherb (Epilobium collinum) belongs to the Onagraceae family within the Epilobium genus. Hairy Willowherb is also known as Broad-leaved Willowherb.
Hairy Willowherb displays an upright, spreading perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Hairy Willowherb produces showy spikes of pink, purple, or white flowers.
Leaf size: approximately 4 inches.
How Often Should You Water a Hairy Willowherb?
Epilobium collinum 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 Hairy Willowherb Need?
Hairy Willowherb thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Hairy Willowherb Prefer?
Epilobium collinum grows best at temperatures of 50–80°F. Hairy Willowherb prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Hairy Willowherb?
Moist, well-draining soil rich in organic matter. Good drainage is essential for Hairy Willowherb to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Hairy Willowherb?
Feed Hairy Willowherb 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 Hairy Willowherb?
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 Hairy Willowherb?
Hairy Willowherb can be propagated through seeds, division. Similar propagation techniques also apply to american willowherb plant care, which shares the same genus.
Is the Hairy Willowherb Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Hairy Willowherb, 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 Hairy Willowherb?
Hairy Willowherb 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 Hairy Willowherb Need?
Hairy Willowherb grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Hairy Willowherb as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Hairy Willowherb 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.
Hairy Willowherb 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 collinum C.C.Gmel., family Onagraceae (first published in Fl. Bad. 4: 265 (1826)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Hairy Willowherb, 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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