North America Native Plant

Spotted Water Hemlock

Botanical name: Cicuta maculata var. maculata

USDA symbol: CIMAM

Life cycle: biennial

Habit: forb

Native status: Native to Canada âš˜ Native to the lower 48 states  

Synonyms: Cicuta curtissii J.M. Coult. & Rose (CICU)  âš˜  Cicuta maculata L. var. curtissii (J.M. Coult. & Rose) Fernald (CIMAC2)  âš˜  Cicuta mexicana J.M. Coult. & Rose (CIME2)   

Spotted Water Hemlock: A Native Plant You Should Never Grow While we love celebrating native plants, there’s one species that deserves a very different kind of attention: spotted water hemlock (Cicuta maculata var. maculata). This plant holds the dubious honor of being one of the most poisonous plants in North ...

Spotted Water Hemlock: A Native Plant You Should Never Grow

While we love celebrating native plants, there’s one species that deserves a very different kind of attention: spotted water hemlock (Cicuta maculata var. maculata). This plant holds the dubious honor of being one of the most poisonous plants in North America, and it’s definitely not one you want anywhere near your garden, family, or pets.

What is Spotted Water Hemlock?

Spotted water hemlock is a native biennial or perennial forb that grows throughout most of the United States and Canada. As a forb, it’s an herbaceous plant without woody stems, but don’t let its innocent appearance fool you. This member of the carrot family produces clusters of small white flowers arranged in umbrella-like formations that might look pretty from a distance, but up close, they spell danger.

Where Does It Grow?

This native plant has an extensive range, growing naturally in almost every U.S. state and Canadian province, from Alabama to Alaska and everywhere in between. You’ll typically find it thriving in wetland areas, along stream banks, in marshes, and at the edges of ponds and lakes.

Why You Should Never Plant Spotted Water Hemlock

Here’s the deal: spotted water hemlock contains cicutoxin, a compound so toxic that even a small amount can be fatal to humans and animals. We’re talking about a plant where a single root the size of a walnut can kill a full-grown cow. The entire plant is poisonous, but the roots pack the most deadly punch.

Symptoms of poisoning include:

  • Nausea and vomiting
  • Abdominal pain
  • Tremors and seizures
  • Respiratory failure
  • Death (often within hours)

There’s no antidote, and medical treatment options are extremely limited. This is not a plant you want to take any chances with, especially if you have children, pets, or livestock.

How to Identify Spotted Water Hemlock

Knowing how to spot this dangerous plant is crucial for safety:

  • Height: Can grow 3-6 feet tall
  • Leaves: Compound leaves with serrated leaflets
  • Flowers: Small white flowers arranged in umbrella-shaped clusters
  • Stems: Often have purple streaks or spots (hence spotted)
  • Habitat: Always found near water sources
  • Root: Large, chambered taproot (extremely toxic)

Safe Native Alternatives for Wetland Gardens

If you’re looking to create a beautiful native wetland garden, there are plenty of safe alternatives that offer similar aesthetic appeal without the deadly risk:

  • Wild bergamot (Monarda fistulosa)
  • Blue flag iris (Iris versicolor)
  • Cardinal flower (Lobelia cardinalis)
  • Swamp milkweed (Asclepias incarnata)
  • Joe Pye weed (Eutrochium species)

What to Do If You Find It

If you discover spotted water hemlock on your property, especially near areas where children or pets play, consider having it professionally removed. Never attempt to remove it yourself without proper protective equipment, as even skin contact with the sap can be dangerous. Always wash hands thoroughly after any potential contact.

The Bottom Line

While we’re passionate advocates for native plants, spotted water hemlock is the exception to the rule. Its extreme toxicity makes it unsuitable for any garden or landscape setting. Instead, choose from the many beautiful and safe native wetland plants that can provide the same ecological benefits without putting your family and pets at risk.

Remember: when it comes to gardening, safety always comes first. There are simply too many wonderful, safe native plants to choose from to ever justify the risk of growing one of nature’s most dangerous specimens.

Spotted Water Hemlock

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Apiales

Family

Apiaceae Lindl. - Carrot family

Genus

Cicuta L. - water hemlock

Species

Cicuta maculata L. - spotted water hemlock

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA