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June 2015
Iris pallida
(Orris Root)
Text and Photographs by Bob Mitchell
The genus Iris is large and diverse with about 280 species arranged in six subgenera. Iris pallida belongs to the
Subgenus Iris, Section Iris which is characterised by having rhizomes and bearded flowers.
Iris pallida was named by Jean-Baptiste Lamarck (1744-1829) in Encycl. Meth. Bot.
3:294 in Paris in 1789, although it was in cultivation in the 13th century when it was
used in perfumery. In ancient time is was used medicinally but not now because
some can be allergic to it. It is native to north Italy and the west Balkans although it
has naturalised in south Europe and was grown commercially over a wide area. Our
plant is reputed to have come from Gallipoli, having been collected and brought
home by a relative in 1915 and grown on as a memento.
Iris pallida, Iris germanica and Iris versicolor are the main sources of orris
root, still used in the perfumery trade. The rhizomes are lifted, the growing tip
removed and replanted while the remainder of the rhizome is cleaned and dried for
3-5 days then sliced to further dry to produce a scent of violets. The rhizome
contains the essence iridine.
Iris pallida ssp pallida is a striking plant with silvery-green leaves and pale
lavender-blue flowers. The sturdy stems may reach 1 metre in height. There are at
least four fragrant flowers on each stem and these flower in succession, thus
extending the flowering season into July. There are two variegated leaf forms: one
silver, the other yellow which gives added year-round interest. Another subspecies
cengialti is dwarfer and stems with two to three flowers which are violet in
colour. This plant is native to north-east Italy.
Iris pallida has been hybridised with the taller and darker Iris germanica to
produce a vast number of Tall, Bearded Irises, much grown by enthusiasts.
Cultivation. Iris pallida is
easy to grow in a rich, well
drained soil in full sun. It is
remarkably free from pests and
diseases.
Propagation. Every three or
four years, and after the flowers are over, they should be lifted, the tuber
divided, the dead roots trimmed and replanted in an enriched soil. To
prevent wind rock the leaves can be cut back to half their length.
Position. Iris pallida is growing at the north end of the herbaceous border
at the front edge. Iris pallida ssp cengialti is in the Rock garden.
References:
Grieve, Mrs M. 1971. A Modern Herbal. Hafner.
Mabberley, D.J. 2008. Mabberley’s Plant-Book. Cambridge.
Mathew, Brian. 1981. The Iris. Batsford.
Tutin, T.G. et al. 1980. Flora Europaea Vol 5. Cambridge.
Walters, S.M. et al. 1986. The European Garden Flora Vol 1. Cambridge.
https://www.sagrona.com/sagrona/irises/Irises.jsp