''Thunbergia gregorii'', commonly known as orange clockvine or orange trumpet vine, is a herbaceous perennial climbing plant species in the family

Acanthaceae Acanthaceae is a family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are tropical herbs, shrubs, or twining vines; some are epiphytes. Only a few species are distributed in te ...

, native to East Africa and sometimes cultivated as an ornamental vine. The bright, pure all-orange flowers distinguish it from the related black-eyed Susan vine (''

Thunbergia alata ''Thunbergia alata'', commonly called black-eyed Susan vine, is a herbaceous perennial climbing plant species in the family Acanthaceae. It is native to Eastern Africa, and has been naturalized in other parts of the world. It is grown as an or ...

'').

Spencer Le Marchant Moore Spencer Le Marchant Moore (1 November 1850 – 14 March 1931) was an English botanist. Biography Moore was born in Hampstead. He worked at the Royal Botanic Gardens, Kew, from about 1870 to 1879, wrote a number of botanical papers, and then work ...

described the species in 1894, naming it after

John Walter Gregory John Walter Gregory, , (27 January 1864 – 2 June 1932) was a British geologist and explorer, known principally for his work on glacial geology and on the geography and geology of Australia and East Africa. The Gregory Rift in the Great Rift ...

. Within the genus ''

Thunbergia ''Thunbergia'' is a genus of flowering plants in the family Acanthaceae, native to tropical regions of Africa, Madagascar and southern Asia. ''Thunbergia'' species are vigorous annual or perennial vines and shrubs growing to 2–8 m tall. The ge ...

'', it is most closely related to ''T. alata'', the two being placed in the subgenus ''Parahexacentris''. The common name of clockvine relates to the vine spiralling upwards in a clockwise direction. ''Thunbergia gregorii'' is an evergreen vine that grows to 8–10 ft. tall, or if left without support can become an extensive groundcover. It looks like the related black-eyed Susan vine (''T. alata''), but without the black eye. ''Thunbergia gregorii'' is native to east Africa, and is pollinated by bees. Hardy to -1 C, ''Thunbergia gregorii'' flowers more profusely and even year-round in warmer climates, while restricted to summer and autumn in cooler climates. It has received the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nort ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

. Propagation is by cuttings taken in the summer.

References

External links

* {{Taxonbar, from=Q10637261 gregorii Flora of Africa Garden plants of Africa