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.

Iris japonica Thunb.

A rhizomatous crested iris with fans of strap-shaped, evergreen, dark green leaves and, in late spring, 3-4 flattened, frilly, white or pale lavender-blue flowers per stem, with purple and orange markings on the falls.  To 45cm.  Under favourable conditions it can be very invasive in the garden.  [RHSE, Hortus].  

Horticultural & Botanical History

‘This iris has been cultivated in China for centuries and it is impossible to say whether it is only an introduction into Burma and Japan.’  [Dykes]. 

The Iris chinensis illustrated in Curtis’s Botanical Magazine is clearly Iris japonica: ‘The public are indebted to Mr. Evans of the India-House, for the introduction of this plant from China, where it is a native.

It flowered last year, at different periods, for the first time, in many collections near London; this irregularity of its blowing was occasioned, we presume by its being kept in different degrees of heat, in the stoves of some, and the green-houses of others; Mr. Thomson, Nurseryman of Mile-End, at the close of the year, had it growing very luxuriantly in the open ground; but the very severe winter of 1796-1797, in which the thermometer at Brompton was three degrees below zero, destroyed it; nevertheless, there is no doubt but it will bear the cold of our ordinary winters, and thrive better in the open ground, in a moist situation, than in the stove, or green-house in either of which, however, it will flower very well; and, where the plant is luxuriant, continue to do so for a confiderable length of time, the blossoms being numerous, and unfolding gradually: in a strong plant at Mr. Colvilles’s, Nurseryman, King’s-Road, we counted seven blossoms expanded at one time on its different branches.

It differs from all other known Iris’s, in having a root perfectly of the creeping kind, sending out shoots to a considerable distance, by which it is rendered very easy of propagation; its flowers, in form and colour, come nearest to those of Iris cristata, and have a considerable degree of fragrance.’  [BM t.373/1797]. 

Johnson’s Dictionary gives a date of introduction to Britain of 1792 for Iris chinensis, the description of which fits I. japonica.  

History at Camden Park

Listed in all published catalogues [B.230/1843].


Iris chinensis L. = Belamcanda chinensis (L.) DC. which see.

Iris chinensis Bunge. (1872) = Iris tectorum Maxim.  

Published Oct 29, 2009 - 05:21 PM | Last updated Jul 23, 2010 - 05:31 PM

Figured is a root and flowering stem with pale blue and yellow flowers.  Curtis's Botanical Magazine t.373, 1797.

Iris japonica Thunb. | BM t.373/1797 | BHL

Family Iridaceae
Region of origin

China, Burma and Japan

  • Iris chinensis Curt. 
Common Name

Japanese Iris

Name in the Camden Park Record

Iris Chinensis 

Confidence level high