A Forager’s Guide to Horseweed (Erigeron Canadensis)

Horseweed (Erigeron canadensis) is an edible and fast-growing plant commonly found in North America. Horseweed is considered an invasive plant in many areas. The leaves, seedlings, and roots are edible.

Erigeron canadensis plant profile

Scientific name Erigeron canadensis, horseweed’s taxonomy places it in the Asteraceae family, which includes other well-known wildflowers and garden favorites such as daisy, aster, and sunflower.

Horseweed is also known by a number of other synonyms, such as:

  • Conyza canadensis
  • Horse balm
  • Canadian horseweed
  • Coltstail
  • Marestail
  • Butterweed
  • Canadian fleabane

Horseweed is a summer annual that can grow over 6 feet tall if left unchecked.

Its long stems give rise to a tight inflorescence with a white ray and yellow disc florets at the ends.

Although the flower color for horseweed is typically white, it can occasionally be found in purple as well.

Erigeron canadensis
Horseweed (Erigeron canadensis)

Where does horseweed grow?

In addition to areas of North America, particularly California and Canada, where it’s referred to as Canada fleabane, horseweed can grow in areas of Asia and Europe.

Horseweed is an opportunistic plant and commonly found in meadows and disturbed areas like:

  • Roadsides
  • Construction sites
  • Pastures

It can occasionally be found in wetlands, but they are not a primary habitat.

It is hearty enough to tolerate a number of soil types and will develop a tap root as it grows to satisfy its water needs.

In the United States, it grows most prolifically in USDA hardiness zones 6-9.

Conyza canadensis
Horseweed (Conyza canadensis or Erigeron canadensis)

Is horseweed invasive?

Horseweed is considered an invasive plant in many areas. It has now been placed on the plant list of dangerously invasive weeds in Ohio. It is also listed in the USDA plants database as an invasive species.

Each plant can produce thousands of seeds readily dispersed by wind and wildlife. These seeds then germinate in areas where they aren’t wanted.

Horseweed is resistant to a wide variety of herbicides, making management a challenge. Glyphosate-resistant horseweed produces many seeds, which means it can easily insert itself into the landscape and spread, eventually choking off more desirable plants or crops.

How to identify Erigeron Canadensis?

Horseweed seedlings can sprout in fall, spring, or summer.

As it grows, it develops hairy, oblanceolate leaves that come to a point at the tips and grow in a spiral shape up the stem. As the plant matures, the leaves become alternate, irregularly toothed, and lack petioles.

The flowerheads grow in small, daisy-like clusters at the top of the stem, covered lightly in fine hair. The florets are small, with each flowerhead containing roughly 20 disc-shaped florets. The flowers will bloom throughout the summer, with a bloom time from June – September.

One of its most distinguishing features is its bracts which have a brownish inner surface and lack the red dot at the tip. These attributes, particularly the hairs found on the bracts, are common to many related species.

Horseweed flowerhead
Horseweed flowerhead

Is it poisonous in any way?

Horseweed is not considered a highly poisonous plant. The flowers and leaves can cause mild irritation to some people’s skin.

It is also known to irritate horses’ nostrils and has also been reported to be toxic in sheep and cattle.

Those reports are anecdotal at this point and have not been verified.

What parts of horseweed are edible?

The leaves, seedlings, and roots are edible.

Native Americans would dry the leaves and use them as medicinal tea to treat dysentery. It can also be used as a diuretic and increases perspiration.

In some cultures, the root of horseweed has been boiled and used as a tea to help treat menstrual cramps.

It has also been used in the bedding material for dogs to ward off fleas. Hence the name, fleabane.

What does horseweed taste like?

Horseweed is reminiscent of tarragon and can be used as a seasoning to flavor many dishes.

When broken, the leaves of horseweed give off an aroma similar to carrots.

How to cook with horseweed

  • Horseweed is typically used as a seasoning. Its herbaceous flavor can add depth to any meat dish.
  • The young plants can be boiled and used as a potherb in soups and stews.
  • Some enjoy the leaves boiled and served as a side dish like spinach.

How to prepare horseweed tea

  • dried horseweed leaves: 1 tablespoon
  • 1 cup of boiling water

Steep dried horseweed leaves for about 30 mins. It is recommended not to consume more than 1-2 cups daily.


Lorin is a writer, photographer and nature enthusiast in Sacramento, CA. In addition to gardening, she makes a regular practice of forging for edible plants and flowers. Nature nourishes if you know where to look.

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