Canadian horseweed.

En un coup d'œil

Niveau d'entretien

Facile

Type de plante

Annual herb

Lumière

Full sun

Lumière en intérieur

Soleil direct

Arrosage

Tous les 7 à 14 jours

Taille adulte

5 feet

Croissance

Rapide

Rusticité

USDA 3 à 9

Floraison

Mid summer to mid autumn

Entretien

This plant thrives in full sun and well drained soil. Watch for wilting during extreme heat, though it is quite drought tolerant once established. It is a prolific seeder, so pull it before flowers fade if you want to limit its spread.

Arrosage

Water only when the top inch of soil feels dry to the touch.

Engrais

This plant generally does not require supplemental fertilizer.

Taille

Remove spent flower heads to prevent unwanted self seeding.

Rempotage

As an annual, this plant is typically not repotted.

Sol

Well drained, sandy or loamy

pH du sol

6.0 to 7.5

Température

-20 à 35°C

Humidité

30 à 70%

Sécurité

Humains

The plant may cause skin irritation in sensitive individuals upon contact.

Enfants

Keep away from children as the plant can cause skin irritation if handled.

Allergènes de contact

The foliage contains compounds that can cause contact dermatitis.

Allergènes aéroportés

The abundant windborne seeds and pollen may trigger respiratory discomfort in sensitive people.

Comestibilité

While historically used in herbal medicine, it is not considered a food crop and should be avoided.

Comment l'identifier

• Tall, unbranched hairy stem
• Narrow, lance shaped leaves
• Small white flower heads
• Forms a basal rosette initially

Hauteur

0,3 à 1,5m

Envergure

0,15 à 0,45m

Feuilles

green, deciduous

Fleurs

white, yellow, 0,5 à 1cm

Fruits

tan, Autumn

Problèmes courants

• Powdery mildew — A fungal infection that appears as white dust on leaves during humid weather.

La cultiver

Multiplication

seed

Quand planter

spring, autumn

Plant in sunny, open areas to mimic its natural meadow habitat.

Bonnes associations

• Asclépiade commune — They share similar habitat requirements in open meadows.
• Verge d'or — Both species provide late season nectar for pollinators.

Espèces similaires

• Erigeron philadelphicus — It has similar flower structures but prefers moister soil.

Science

Famille

Asteraceae

Genre

Erigeron

Ordre

Asterales

Classe

Magnoliopsida

Région d'origine

North America

Préservation

It is considered a common weed in many regions and is not of conservation concern.

It thrives in open, disturbed habitats where it acts as an early successional species.

Intérêt pour la faune

nectar source, larval host plant

Pollinisateurs

abeilles, papillons, coléoptères

Utilisations

pollinator garden, meadow restoration, herbal history

Taxonomie vérifiée avec le GBIF.

Ce qu'on demande souvent

Is this plant invasive?

It is native to North America but can act as an aggressive colonizer in disturbed areas.

Does it need much water?

It is quite drought tolerant once established.

D'où vient le nom

The genus name comes from Greek words meaning early and old man, referring to the white, hair-like pappus. The species name indicates its origin in Canada.

Bon à savoir

• It is also known as horseweed.
• The plant was once used to treat various ailments in traditional medicine.
• It is a pioneer species that quickly covers bare soil.