Thunbergia laurifolia Lindl.

First published in Gard. Chron. 1856: 260 (1856)
This species is accepted
The native range of this species is Arunachal Pradesh to Peninsula Malaysia. It is a liana and grows primarily in the wet tropical biome.

Descriptions

Kew Species Profiles

General Description

Thunbergia laurifolia is a vigorous climber from Asia. The generic name Thunbergia commemorates Swedish physician and botanist Carl Peter Thunberg (1743-1828), who was a protégé of the great Swedish naturalist Carl Linnaeus. The specific epithet laurifolia refers to its laurel-shaped leaves.

It is cultivated as an ornamental in gardens in tropical regions and in heated glasshouses in temperate regions. It is used medicinally in Thailand and Malaysia, although it is considered an invasive in other tropical regions.

Thunbergia laurifolia leaves are reported to have detoxifying effects, and in Thailand they are used as an antidote for poisons and in the treatment of drug addiction. Herbal teas and capsules containing T. laurifolia are sold in Thailand, where they are known as rang jeud.

A Thai study published in 2012 suggested that laurel clock vine has antioxidant and anti-inflammatory properties. It concluded that it may be effective in treating inflammations caused by Opisthorchis viverrinia (southeast Asian liver fluke), a parasite that attacks the liver and is endemic in northern areas of Thailand, Vietnam, Cambodia and Laos.

Species Profile
Geography and distribution

Thunbergia laurifolia is native to India, Burma and Malaysia. It grows in moist areas at low elevations and requires a frost-free environment.

It has been introduced to many tropical regions as an ornamental, but in countries such as Australia it is now considered an invasive weed (along with its close relative Thunbergia grandiflora ). It smothers native vegetation and is therefore considered a threat to Australia's biodiversity in several areas including remnant tropical rainforests across northern Australia.

Description

Overview: A vigorous, hairless, woody vine with tuberous roots, climbing by twining stems and reaching a length of 12 m or more in one season.

Leaves: In opposite pairs. Hairless, usually two to four times as long as they are wide. Lower half of the leaf sometimes irregularly lobed.

Flowers: Petals joined at base to form a short, broad tube with a yellowish throat, opening out into five rounded, lavender to blue (occasionally white in the wild) petals. Calyx (whorl of sepals) with glands at the edge only. 

Flowers are borne on hanging racemes (bearing four or more individual flowers) that can grow up to 1.8 m long.

Fruits: Large beaked capsules with a globose basal (fertile) portion, often compared to a duck's beak. Capsules are loculicidal (split into cells at maturity).

Laurel clock vine is similar in appearance to Thunbergia grandiflora , but has longer, thinner leaves; its young stems and leaves are hairless.

Uses

Laurel clock vine is a popular ornamental in the tropics, where it is grown for its attractive flowers and foliage.

In Thailand and Malaysia, the leaves are dried and crushed and drunk as a tea.

Cultivation

In tropical regions, laurel clock vine can be cultivated outdoors and is often grown on a trellis as a screen or over a pergola. This vigorous climber requires hard pruning each year to contain it. A slightly acidic soil is required, which should be fertile and freely draining.

In temperate climates, laurel clock vine should be grown in a heated glasshouse because it is frost-tender. When cultivated in this way, it enjoys a long and prolific flowering period (Kew's glasshouse specimens flower from March to November). Although still a vigorous climber in a glasshouse environment, its maximum size is significantly less than when it grows in the wild.

It can be propagated by seed or by using stem or root cuttings.

This species at Kew

Laurel clock vine can be seen in the tropical section (zone 1) of Kew's Princess of Wales Conservatory. This specimen was planted in 2012, and the adjacent image shows just one year's growth!

The cultivar Thunbergia laurifolia 'Augustas Blue' can be seen in Kew's Palm House.

Pressed and dried specimens of Thunbergia laurifolia are held in Kew's Herbarium, where they are available to researchers by appointment. The details of some of these specimens, including images, can be seen online in Kew's Herbarium Catalogue.

A specimen of Thunbergia laurifolia wood is held in Kew's Economic Botany Collection in the Sir Joseph Banks Building, where it is available to researchers by appointment.

Distribution
India, Malaysia
Ecology
Tropical forests, as a climber on trees.
Conservation
Not assessed according to IUCN Red List criteria.
Hazards

None known.

[KSP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Acanthaceae (part 1), Kaj Vollesen, Flora of Tropical East Africa, 2008

Morphology General Habit
Vigorous woody twiner to 25 m or more, forming large tangles and often completely covering large trees; young branches glabrous or puberulous at nodes.
Morphology Leaves
Leaves glossy; petiole 1.5–5 cm long, glabrous; lamina lanceolate to triangular ovate, largest 13–20.5 × 4–10.5 cm, apex acuminate, base truncate to cordate, without or with rounded to hastate lobes, margin subentire or with a few large teeth, glabrous, with whitish pustules along major veins above.
Morphology Reproductive morphology Flowers
Flowers in pendulous racemoid cymes to 30 cm long; peduncle to 11 cm long, glabrous, with a pair of leafy sessile bracts to 8 × 4.5 cm at base of cyme; pedicels 2–4.5 cm long, glabrous; bracteoles oblong to obovate, 2.5–4 × 1–2 cm, subacute to rounded, apiculate, truncate at base, glabrous.
Morphology Reproductive morphology Flowers Calyx
Calyx an entire or slightly undulate puberulous rim.
Morphology Reproductive morphology Flowers Corolla
Corolla pale mauve to mauve or purple; cylindric tube ± 1 cm long; throat broadly campanulate, 3–4 cm long, 2–3 cm in diameter apically; lobes 3–4 × 3–4 cm.
Morphology Reproductive morphology Flowers Androecium Stamens Filaments
Filaments 9–15 and 11–17 mm long, glabrous; anthers narrowly oblong, 7–9 mm long, indistinctly apiculate, bearded at base and almost to apex along one side with long hairs with small lateral spinules; all thecae spurred, spurs 4–5 mm long, flattened.
Morphology Reproductive morphology Fruits
Capsule subglobose, 13–15 mm in diameter, glabrous, beak 25–30 mm long, parallel-sided.
Morphology Reproductive morphology Seeds
Seed 8–12 mm in diameter.
Ecology
Margins and clearings of wet lowland rainforest, sometimes disturbed; 850–1200 m
Distribution
Range: Native of India and SE Asia, widely cultivated in East Africa and occasionally naturalized Flora districts: U4 T3 Range: Uganda. Range: Native of India and SE Asia, widely cultivated in East Africa and occasionally naturalized Range: Tanzania.
[FTEA]

Uses

Use
Ornamental, medicine.
[KSP]

Common Names

English
Laurel clock vine

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0
  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Herbarium Catalogue Specimens

    • 'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.
    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/
  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Species Profiles

    • Kew Species Profiles
    • http://creativecommons.org/licenses/by-nc-sa/3.0