Alliaria petiolata

Tracheophyta MagnoliopsidaCruciferaeAlliariaAlliaria petiolata


A biennial or monocarpic herb, found in a wide range of habitats including disturbed woodland, woodland edges and clearings, shaded hedge banks, river-banks, the base of walls, road verges, waste ground, farmyards and gardens. It grows especially well on relatively fertile, moist soils, but avoids only the most acidic sites. Generally lowland, but reaching 535 m S. of Garsdale Head (N.W. Yorks.).



World Distribution

European Temperate element; also in C. Asia and widely naturalised outside its native range.

© S. Hammonds

Broad Habitats

Boundary and linear features (eg hedges, roadsides, walls)

Light (Ellenberg): 5

Moisture (Ellenberg): 6

Reaction (Ellenberg): 7

Nitrogen (Ellenberg): 8

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.6

July Mean Temperature (Celsius): 15.1

Annual Precipitation (mm): 935

Height (cm): 120

Perennation - primary

Biennial, including monocarpic perennials

Life Form - primary




Clonality - primary

Little or no vegetative spread

Comment on Clonality

"CTW say it sometimes persists by root buds, but CPE say usually monocarpic"

Count of 10km squares in Great Britain: 1990

Count of 10km squares in Ireland: 367

Count of 10km squares in the Channel Isles: 9

Atlas Change Index: 0.03

Weighted Changed Factor: -4

Weighted Change Factor Confidence (90%)


JNCC Designations


Atlas text references

Atlas (50d)
Anderson RC, Dhillon SS, Kelley TM
1996.  Aspects of the ecology of an invasive plant, garlic mustard (Alliaria petiolata), in Central Illinois. Restoration Ecology. 4(2):181-191.
Cavers PB, Heagy MI, Kokron RF
1979.  The biology of Canadian weeds. 35. Alliaria petiolata (M. Bieb) Cavara and Grande. Canadian Journal of Plant Science. 59:217-229.
Grime JP, Hodgson JG, Hunt R
1988.  Comparative Plant Ecology.
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Jalas & Suominen (1994)
Meusel H, Jäger E, Weinert E
1965.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
Rich TCG
1991.  Crucifers of Great Britain and Ireland. Botanical Society of the British Isles Handbook no. 6.