Quick Facts

Quick facts

  • Devil's Trumpet (Datura metel) is a robust, bushy, annual herb with green or purple stems, green leaves (sometimes tinged purple) and white, yellow or purple trumpet-shaped flowers.
  • It is found sporadically in urban areas of Australia or sometimes close to habitation in remote areas.
  • Devil's Trumpet is toxic to stock and people but no records of poisoning have  been attributed to this species.
  • Seeds are spread usually by humans because it is grown as a garden ornamental.
  • It is mainly found as a garden escape or persisting in derelict or abandoned gardens.

What Does It Look Like?

What is it?

Devil's Trumpet (Datura metel) is a much-branched, bushy, annual herb growing to 1 m high. The stems are green or often tinged purple (sometimes entirely purple), without hairs or almost so on mature parts. The leaves are alternately arranged along the stem, stalked, green, often strongly tinged purple, with few or no hairs, oval to broadly oval in outline (widest below the middle), 100–140 mm long and 50–120 mm wide, sometimes up to 160 x 150 mm, with  16 cm long and 15 cm wide, with a few short, broad angular lobes on the leaf edges margins, especially towards the base.

The flowers are borne singly in the branch forks and are shortly stalked; they are usually double or triple in form, especially when purple or yellow, but sometimes single, especially when white. The flowers are 140–200 mm long, often purple outside and white inside, sometimes yellow and (in Australia) rarely white, trumpet-shaped, with 5 short, broad, each ending in a narrow tip (overall appearance 5-lobed).There is a tubular green or purple calyx (outer covering) extending for only about a third of the the total flower length from the base; it usually has 5  but sometimes up to 9 teeth.

Devil's Trumpet has capsular fruits that are tuberculate or covered in numerous short, blunt prickles; the capsules are turned downwards.  At maturity, the capsule body is very broadly egg-shaped to globular, 30–40 mm long,  and covered in numerous conical tubercles (blunt prickles) all more or less equal in length and mostly 2–5 mm long, the capsules rarely almost smooth. The capsules break up unevenly from the tip, shedding a large number of seeds. The seeds are D-shaped, tapered towards the base, with a smooth, deep furrow along the margins, yellow to brownish yellow, 4–5 mm long (Haegi 1976; Purdie et al. 1982).

For further information and assistance with the identification of Devil's Trumpet, contact the herbarium in your state or territory.

Flower colour

Purple and white; sometimes yellow (rarely white).

Growth form (weed type/habit)

Robust, bushy, annual herb

Where it currently grows? Preferred habitat

Devil's Trumpet appears to prefer open disturbed habitats in areas near habitation, where water and soil nutrients are available  (AVH 2021).

Are there similar species?

Devil's Trumpet is quite distinctive. It is somewhat similar to Common Thornapple (Datura stramonium) in overall appearance  but Common Thornapple has much smaller flowers (only 60–85 mm long) and upright, sharply-prickly capsules that split evenly into 4 segments when ripe. In Devils' Trumpet the flowers are 140–200 mm long and the capsules are nodding, they are covered in blunt tubercles and break up unevenly when ripe (Haegi 1976; Purdie et al. 1982).

Why Is It A Weed?

What are its impacts?

Agriculture: Devil's Trumpet is potentially a significant weed because it is toxic to stock (as well as people), but there are only minor occurrences of the plant outside cultivation in Australia and there are no records of poisoning attributed to this species (Haegi 1976; Purdie et al. 1982).

How does it spread?

Devil's Trumpet is dispersed by seed,  principally by humans because it is grown as a garden ornamental.  

What is its history in Australia?

Devil's Trumpet was introduced to Australia as an ornamental plant. Its year of introduction is unknown, but the earliest known record is from 1923 for a specimen taken from a plant in Sydney (Haegi 1976).

How To Manage It?

Best practice management

Non-chemical control: Mechanical control: Mechanical removal of Devil's Trumpet is effective for small infestations.

Chemical control: Small plants are likely to be susceptible to herbicide but this form of control may be ineffective for mature plants (Parsons & Cuthbertson 2001).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au 

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Devil's Trumpet is an annual plant. Flowers may be produced when the plant is only 2-5 weeks old. It flowers and fruits throughout the summer and autumn, but is generally does not survive cold winter conditions, sometimes being killed by frosts (Parsons & Cuthbertson 2001).

Where Is It Found?

Which states and territories is it found?

NSW, QLD, WA

What areas within states and territories is it found?

Devil's Trumpet is only very sparingly naturalised in Australia: all records are associated with previous cultivation in gardens. Sites from which possibly self-sustaining populations have been recorded are scattered and occur in warmer parts of Western Australia, New South Wales and Queensland (AVH 2021).

Where does it originate?

Devil's Trumpet probably originated in central America, possibly the West Indies (Symon & Haegi 1991; GRIN 2008).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

NT, TAS, WA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Datura metel

Other scientific names (synonyms)?

Datura alba Rumph. ex Nees

Does it have other known common name(s)?

Thornapple, Purple Horn of Plenty, Hindu Thornapple

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