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Bardane

Arctium minus (ARK-tee-um MY-nus)

Family: Asteraceae Non-native Herbaceous

Common Burdock is a weedy, biennial, herbaceous wildflower belonging to the Aster family. Native to Europe, it is now widely distributed in many parts of the world. Accidentally introduced to the U.S., it is tenacious and aggressively invades disturbed areas, empty lots, parks, roadsides, prairies, fields and pastures. This plant is on the Federal USDA list of Introduced, Invasive and Noxious Plants and is found across most of North America. Some states list this plant as invasive, but North Carolina is not yet one of them. Once established, growth is difficult to eradicate due to deep tap roots and copious amounts of seed that disperse widely and remain viable for a long while even if plants are destroyed. A single plant can produce 15,000 seeds. Robust growth potentially competes with beneficial native species. The first year's growth forms a short, dense rosette of leaves. In its second year, it bolts to heights 3-6 feet, develops very large heart-shaped leaves, pink to purple thistle-like flowers on branched stems, and slender tap roots growing to depths of one foot. Clusters of purple flowerheads are arranged on short stalks on the upper ends of stems. Flowerheads consist of many disk florets and globular bracts terminating in fine, sharp hooks forming prickly burs that aid in seed dispersal by latching onto animals, birds, or hay bales. Burs are very difficult to remove and reportedly have killed small birds and bats that become entangled. Fruits (achenes) within these burs contain sharp, minute bristles (pappas hairs) that easily become windborne and, if exposed to them, can cause severe eye, skin, and respiratory irritation and/or infection in humans, dogs, horses or other livestock. In dairy animals, Common Burdock may taint milk if ingested in sufficient quantity. The pollen from the blooms is collected by bumblebees, honeybees, Miner bees and Leaf-cutting bees, who also feast on the nectar. The foliage is a food source for the caterpillar of the Painted Lady butterfly. It prefers full sun locations with moist, well drained soil rich in organic matter and nitrogen. It may host root rot and powdery mildew, potentially impacting agricultural crops. In Asia and other parts of the world, Common Burdock has been cultivated for for its edible roots and stems and medicinal uses. Cultivated plants are sown from seed in summer and first-year roots are harvested by late autumn before becoming too fibrous. After peeling away the outer husk of young stems, the pith can be eaten as a vegetable. Insects, Diseases, and Other Plant Problems: This plant is weedy, invasive and difficult to eradicate once established. It is susceptible to powdery mildew and root rot with potential to impact agricultural plants. Burs and bristles may cause severe eye, skin or respiratory problems in humans, dogs, horses, and other livestock. Burs are difficult to remove from animals and clothing.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 60 attributes.

How it fits the guild

Guild layer 4 - Herbaceous Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Arctium lappa
Fills a similar niche Impatiens hawkeri Ocimum basilicum Verbena canadensis
Similar, less problematic Echinacea purpurea Liatris

Full plant profile

Growing Conditions
Plant type
Edible; Herbaceous Perennial; Perennial; Weed; Wildflower
Life cycle
Biennial
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt)
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage
NC region
Coastal; Mountains; Piedmont
Growth rate
Rapid
Maintenance
Low
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Erect
Texture
Coarse
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Cordate; Ovate
Leaf margin
Dentate; Undulate
Leaf feel
Rough
Leaf size
> 6 inches long, > 6 inches wide
Hairs present
Yes
Leaf detail
Leaves are very large, up to 2 feet long by 1.5 feet wide, and heart-shaped (like "elephant ears") with wooly hairs on the underside. The largest leaves are at the base of the plant and decrease in size progressing upward along the stem. Lower leaves have hollow stalks (petioles) with a groove on the upper surface.
Flower color
Pink; Purple/Lavender
Flower form
Cyme
Flower shape
Tubular
Flower size
< 1 inch
Flower detail
Pink to purple flowerheads are approximately 3/4-1 inch in size and arranged on stalks. Flowerheads are comprised of many disk florets and needle-thin bracts that terminate in a sharp, hooked tip. There are no ray florets on the flowerhead. After flowers whither, the globular bracts turn brown and enclose the flowers, forming a spiked bur covered with looped ends. This design is highly effective in clinging to animals, birds or clothing and aids in dispersal of seed. Burs may be very difficult to remove.
Bloom time
Fall; Summer
Fruit color
Brown/Copper
Fruit type
Achene
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Achenes are oblong and have fine, minute bristles (pappas hairs) on one end that soon fall off and easily become airborne. These can be seriously irritating to humans or other mammals (particularly dogs, horses, or livestock) if exposed to eyes, skin, or the respiratory tract.
Stem color
Green; Red/Burgundy
Stem detail
Young stems have white hairs, resembling cobwebs. Second year stems are green or reddish green, stout, smooth with longitudinal veins, and round or slightly ridged in cross section.
Wildlife & Ecology
Native status
Non-native
Origin
Native to Europe, Middle East, Baltic States and North Africa
Distribution
Europe, Asia, North Africa, Canada and South America. In the U.S. it is found in the lower 48 states except Florida.
Wildlife value
Bees, butterflies and skippers are attracted.
Attracts
Bees; Butterflies; Pollinators
Play value
Attracts Pollinators; Wildlife Food Source
Food & Medicine
Edible parts
Leaves; Flowers; Roots
Harvest time
Fall; Winter
Fruit type
Achene

Edibility

Primarily the roots are edible. Young leaves and immature flower stalks are also edible before flowers appear.

Uses (ethnobotany)

This plant has been used in Europe and Asia as a food source (roots and leaves) as well as for medicinal purposes.

Landscape Use
Garden tags
#edible weed #lavender flowers #bracts #purple #lavender #fields #pink flowers #purple flowers #globular #summer flowers #fall flowers #biennial #herbaceous #aggressive #weedy
Problems & Resistance
Problems
Contact Dermatitis; Problem for Dogs; Problem for Horses; Spines/Thorns; Weedy
Propagation
Seed

Planted at Hunnicutt

Nobody’s planted this one yet.