Water Hemlock Plant Care
Cicuta virosa L.
Updated · Sources · How we source care data
Cicuta virosa, the cowbane or northern water hemlock, is a poisonous species of Cicuta, native to northern and central Europe, northern Asia and northwestern North America.
Every 5–7 days
Full sun to partial shade
60–75°F
40–60%
At a glance
How do you care for Water Hemlock?
Water Water Hemlock 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. It is reported as toxic to pets, so keep it out of reach of pets.
Where Is the Water Hemlock Native To?
What Is the Water Hemlock?
Water Hemlock (Cicuta virosa) belongs to the Apiaceae family within the Cicuta genus. Water Hemlock is native to northern and central Europe, northern Asia and northwestern North America. Water Hemlock is also known as Cowbane, Poison Hemlock.
Water Hemlock displays a tall upright perennial growth habit, reaching up to 5 ft tall with a spread of approximately 2 ft. Water Hemlock produces small white flowers arranged in umbels.
Leaf size: approximately 8 inches.
How Often Should You Water a Water Hemlock?
Cicuta virosa 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 Water Hemlock Need?
Water Hemlock thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Water Hemlock Prefer?
Cicuta virosa grows best at temperatures of 60–75°F. Water Hemlock prefers humidity levels of 40–60%.
Temperature
60–75°F
Humidity
40–60%
What Soil Mix Works Best for a Water Hemlock?
Rich, moist soil with good drainage. Good drainage is essential for Water Hemlock to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Water Hemlock?
Feed Water Hemlock 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 Water Hemlock?
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 Water Hemlock?
Water Hemlock can be propagated through seeds. Similar propagation techniques also apply to bulb-bearing water hemlock plant care, which shares the same genus.
Is the Water Hemlock Toxic to Pets and Children?
Toxic (caution)
Reported as toxic in our plant data. Not verified by the ASPCA.
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 Water Hemlock?
Water Hemlock is susceptible to aphids, spider mites, 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 Water Hemlock Need?
Water Hemlock grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Water Hemlock is native to northern and central Europe, northern Asia and northwestern North America. In cooler regions, grow Water Hemlock as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Water Hemlock 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 Cicuta genus — compare its care with other Cicuta species on PlantoScan.
Cicuta is part of the Apiaceae plant family — browse all Apiaceae genera and species.
Water Hemlock 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: Cicuta virosa L., family Apiaceae (first published in Sp. Pl. : 255 (1753)) — World Flora Online record, IPNI name record.
- Pet toxicity: Water Hemlock is reported as toxic to pets in our plant data (not verified by the ASPCA), so treat it with caution. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- 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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