Colin Mills, compiler of the Hortus Camdenensis, died in late November 2012 after a short illness. As he always considered the Hortus his legacy, it is his family's intention to keep the site running in perpetuity. It will not, however, be updated in the near future.

Tweedia coerulea D.Don ex Sweet

Frost tender, erect, evergreen subshrub with twining, hairy stems, lance-shaped downy leaves, to 10cm long, and 3- or 4-flowered cymes of oblong-petalled, sky-blue flowers, to 2.5cm across, ageing to purple, in summer and autumn.  To 1m.  [RHSE, Hortus, Hilliers’].

Horticultural & Botanical History

‘A most highly interesting Asclepiadeous plant, for which I am indebted to Mr. Niven, the excellent Curator of the Glasnevin Botanic Garden, in which Establishent it flowered in July, 1837, and whence the specimen here represented was sent, accompanied by a beautiful figure.  It was discovered by Mr. Tweedie, probably in Tucuman, (though the locality is not mentioned,) and communicated to Mr. Niven with the name of Asclepias Asedra.  Its large flowers, of a singularly changeable blue colour, with exserted scales from the tube, remind one rather of a Boragineous than an Asclepiadeous plant.  In Genus it borders upon Oxypetalum and Tweedia; and I think it may safely be referred to the latter.’  [BM t.3630/1838].

Paxton’s Magazine of Botany noticed it at Rollinson’s Nursery, Tooting: ‘A most interesting greenhouse or half-hardy plant, said to be of twining habits.  The specimen which is now flowering in the greenhouse of these gentlemen grows nearly erect, and the beautiful blue blossoms are produced abundantly from the extremities of the shoots.  It is an exceedingly ornamental plant, and should be in every collection.’  [MB p.238/1838].  It was figured in this journal later in the year: ‘Perhaps no plant loses more of its beauty by confinement in a stove or greenhouse than Tweedia caerulea.  But when transplanted to the open border in the summer months, the blossoms assume a most lively azurean blue; and, being exceedingly numerous, produce a highly ornamental effect.’  [Paxton’s Magazine of Botany]. 

‘Mr. Tweedie discovered this pretty flower in Buenos Ayres [in 1832].  Plants were raised in the Glasgow Botanic Gardens.’  [FC p.293/1837].  This journal also figured the plant.  [FC p.193/1839].  

History at Camden Park

Listed in the 1850 and 1857 catalogues [T.966/1850].


Published Feb 24, 2010 - 09:44 AM | Last updated Jul 14, 2010 - 02:55 PM

Figured is a climber with downy leaves and sky-blue starry flowers.  Curtis's Botanical Magazine t.3630, 1838.

Tweedia coerulea D.Don ex Sweet | BM t.3630/1838 | BHL

Family Asclepiadaceae
Region of origin

South America

  • Oxypetalum coeruleum Dcne.
  • Tweedia versicolor Hook. 
Common Name
Name in the Camden Park Record

Tweedia cœrulea 

Confidence level high