Onion weed (Asphodelus fistulosus)

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Onion weed is an upright herb with onion like leaves and small white or pinkish flowers that have a stripe on each petal. It invades rangelands, pastures, crops and natural vegetation.

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How does this weed affect you?

Onion weed competes with:

pastures, especially poorer pastures, reducing productivity
cereal crops, reducing yields
native plants including plants in undisturbed woodlands.

Human health

Onion weed may cause dermatitis in some people.

What does it look like?

Onion weed is an upright annual, biennial or perennial herb 20–80 cm tall. It has onion-like leaves, but it is not in the same plant family as onions and doesn’t smell like onions.

Leaves are:

3–55 cm long and up to 8 mm wide
cylindrical, flattened on one side, tapering to a point
hollow
grow from the base of the plant.

There are usually more than 40 leaves per plant.

Flowers are:

white or sometimes pale pink with 6 petals that each have a red-brown stripe downthe centre
15–20 mm wide
alternate along the flower stems
present mainly from winter to spring.

Seedpods are:

rounded capsules
pale red brown to sandy brown
4–6 mm wide
divided into 3 sections each containing 1 or 2 seeds.

Seeds are:

black or brown
triangular or spindle shaped
3–4 mm long
wrinkled or pitted.
us, without a taproot.

Flowering stems are:

3–80 cm long and 2.5–7 mm wide
upright, rigid and hollow
branched towards the top.

Roots are:

yellow
long and fibrous.

Similar looking plants

Onion weed looks similar to other introduced plants including:

Three-cornered garlic (Allium triquetrum), which has flattened, strap-like leaves up to 17 mm wide, and only 11 leaves per plant.
Crow garlic (Allium vineale), which has dense clusters of flowers or bulbils at the top of the stems. The flowers do not have a stripe running down the centre of each petal.
False onion weed (Trachyandra divaricata), which has fleshy, flat leaves that may be up to 1 m long. Each plant has fewer leaves, up to 19.

Onion weed also looks similar to the native plant:

Native leek (Bulbine semibarbata), which has smaller, golden yellow flowers and only up to 20 leaves per plant.

Where is it found?

In NSW, onion weed is widespread and common from the coast to arid inland areas.

Onion weed is native to the Mediterranean region, the Middle East and Macaronesia.

What type of environment does it grow in?

Onion weed grows well in disturbed sites. It grows best in alkaline sandy soils and tolerates low nitrogen soils. Most infestations are in open sites and it has been found growing in:

coastal vegetation including on sand dunes
disturbed areas such as along roadsides and trails
cropping land
rangelands, grasslands and pastures
shrublands and woodlands.

How does it spread?

By seed

Onion weed plants usually start flowering when they are about 18 months old. One plant can produce up to 13,000 seeds per year. The seeds can germinate almost year-round.

Seeds are spread:

by wind moving dead plants with seeds still attached
in moving water
by sticking to animals or clothing
via vehicles and farm machinery
in contaminated produce.

References

Guerrero-Eloisa, O.S. (2024) CABI data sheet: Asphodelus fistulosus. CABI Digital Library. Retrieved 15 July 2026 from: https://www.cabidigitallibrary.org/doi/full/10.1079/cabicompendium.75461610

Identic Pty Ltd. and Lucid (2016). Weeds of Australia Fact sheet: Asphodelus fistulosus L. Retrieved: 13 July from: https://keyserver.lucidcentral.org/weeds/data/media/Html/asphodelus_fistulosus.htm

Parsons, W.T., & Cuthbertson, E. G. (2001). Noxious weeds of Australia. 2nd edition. CSIRO publishing.

PlantNET (The NSW Plant Information Network System) (2020). Asphodelus fistulosus L. NSW Flora Online. Royal Botanic Gardens and Domain Trust, Sydney. http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Asphodelus~fistulosus.

More information

Control

Prevention

If possible, avoid taking vehicles or machinery onto infested areas. Clean vehicles and machinery that have been in infested areas before taking them to a site without onion weed.

Request a vendor declaration form when purchasing fodder to limit introducing weeds onto your property.

Physical removal

By hand

If the infestation is small, plants can be dug out. Bag and dispose of any seeding plants to prevent seeds spreading.

Cultivation

In dry regions, cultivating in summer when the soil is dry can kill the plants. Cultivation can be successful if followed by establishing a competitive crop such as lucerne or other legume pastures, that are not grazed in the first year. Fertilizing the crop will help it outcompete onion weed.

Herbicide control

Spray actively growing plants, ensure all of the foliage is covered.

Herbicide options

WARNING - ALWAYS READ THE LABEL
Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this information. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website www.apvma.gov.au

See Using herbicides for more information.

PERMIT 11916 Expires 30/09/2030
Glyphosate 360 g/L (Various products)
Rate: 50 mL per 10 L of water.
Comments: Spray evenly to cover all foliage. Retreatment is essential after flowering. For use in urban bushlands, forests and coastal reserves. See permit for critical use comments.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

Aminocyclopyrachlor 240 g/L (Method® 240 SL)
Rate: 200-500 mL per 100 L of water
Comments: Spot spray with a handgun, hand-held sprayer or backpack sprayer. Thoroughly and uniformly wet the foliage but avoid spraying to the point of run off.
Withholding period: Nil for domestic grazing. See label for livestock export conditions.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate

Amitrole 250 g/L + Ammonium thiocyanate 220 g/L (Various products)
Rate: 1.1 L per 100 L of water
Comments: Active growth before flowering. Repeat treatments will be required.
Withholding period: Nil
Herbicide group: 34 (previously group Q), Inhibition of lycopene cyclase
Resistance risk: Moderate

Biosecurity duty

The content provided here is for information purposes only and is taken from the NSW Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.

Area	Duty
All of NSW	General Biosecurity Duty All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.

For technical advice and assistance with identification please contact your local council weeds officer.

Reviewed 2026