Greek iris – rainbow – clearly, at least in part, a reference to the colourful flowers in this genus.
Perennial herbs with rhizome or bulb. Leaves mostly basal, 2 ranked and linear to sword-shaped, often in a fan-like arrangement. Stems usually erect, with one or more reduced leaves. Flowers erect, radially symmetrical, 1-several in terminal spathes. Perianth with tube; segments in two different series, the outer ones (known as falls) bent downward and often with a crest, coloured patch (the signal) or ridge of hairs (the beard), the inner segments (called standards) usually spreading or erect, shorter. Stamens free. Style branches petal-like, each pressed over a fall and covering a stamen. Fruit a cylindrical to ellipsoid capsule, round to triangular in section and often with 3-6 ribs; seeds numerous.
An important commercial genus whose members have structurally attractive and colourful flowers.
Species in the wild come from a wide range of habitats from permanent water to dry sandy soils so have wide use in the garden. They are best known in horticulture through the spectacular Bearded Irises which have been the subjects of extensive breeding especially in the USA, but Australia runs second, and it is these that have been variously classified for exhibition purposes according to the kinds of colour variations of the standards and falls. Louisianas rank second to Bearded Iris in Australian sales.
Irises are classified botanically into 6 subgenera, 8 sections and 16 series. Many of these groupings have horticultural names that are well known to gardeners and, since horticultural groupings correspond with the larger botanical ones, the species are presented here under horticultural names. The 6 subgenera are: Iris (Bearded Irises); Limniris (Beardless Irises); Xiphium (Spanish Irises); Scorpiris (Junos); Hermodactyloides (Reticulatas) and Nepalensis (no horticultural name). The subgenus Iris is divided into 6 sections including the horticulturally important Section Iris, the True Bearded or Pogon irises, and the Section Onocyclus. Popular horticultural groups in the subgenus Limniris include: Section Lophiris (Evansia or Crested Irises), and within the Section Limniris are the Series Sibiricae (Siberian Irises), Californicae (Pacific Coast Irises), Hexagonae (Louisianas), and Spuriae (Spurias).
The following account covers a small selection only, with emphasis on those raised in Australia. Lists of those currently available can be obtained from major Iris suppliers including Tempo Two Nursery in Victoria, Rainbow Ridge Nursery in NSW and Iris Acres Nursery in SA.
A historical account Iris pioneers and personalities in Australia by John Baldwin was published in 1987 by the Australian Iris Society.
About 260 species in the temperate zone of the Northern Hemisphere.
Division and offsets (cultivars), or seed (species).
The rhizomes of I. albicans, I. germanica and I. pallida are used in cosmetics and traditional European medicine under the name of orris root. I. tectorum is used in a similar way in E Asia.
Flowers with two different whorls of perianth segments joined in a tube at the base.
Hoog (1980), Kohlein (1987), Mathew (1989), Davis & Jury (1990),Waddick & Zhao (1992), Grosvenor (1997), Species Group of the British Iris Society (1997), Stebbings (1997). Periodicals: Bulletin of the American Iris Society; Newsletter, Bulletin and Year Book of the Australian Iris Society.
Source: (2005). Iridaceae. In: . Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.
Australian introductions include:
White, blue lavender, lemon, gold blend. (Blyth, 1998).
S kiss' Lavender standards, yellow falls with lavender edges.
Creamy white, deep gold signal. (p. Evans, 1997).
Violet with bronze shading on falls.
Yellow and brown.
Violet and gold. (Blyth, 1993).
Tall, lavender and cream. (Blyth, 2000).
Taller, bigger, earlier flowering than the similar 'Goldmania'. (Blyth, 2000).
Gold variety used for floral art. (Blyth, 1989).
Golden yellow with brown veins.
Honey overlaid with bronze. (Sylva, 1996).
Pale purple standards, bronze falls.
Chocolate brown. (Blyth, 1993).
Ruffled powder blue violet with purple veins. (Blyth, 1999).
Lavender blue and gold. (Blyth, 1993).
Lavender blue and creamy white. (p. Evans, 1997).
Pastel lavender, blue and gold. (Blyth, 1993).
Very tall deep violet standards and pale violet falls. (p. Evans, 1997).
Ruffled deep smoky lavender purple with gold signals. (Evans, 1997).
Navy blue with gold signals. (Blyth, 1993).
Pretty laced lemon with deeper gold line. (Blyth, 2000).
Violet to violet-black standards with gold and brown falls. (Blyth, 1999).
A group of hybrids originally bred from I. pallida and I. variegata, with later contributions from I. trojana and other species; they are the most popular commercial group.The oldest cultivars are diploids with perianth segments to 9 cm long and 6 cm wide; tetraploids and hexaploids were bred later with progressively broader ruffled segments.
There are thousands of named cultivars - the following is a selection:
Yellow standards, brown falls.
White with dark blue veining.
Full, ruffled blush pink with darker orange-shaded throat.
Very dark indigo-violet standards, almost black falls.
Golden yellow self.
Golden copper standards, deep mahogany falls.
Medium blue, shaded and streaked near edges with grey.
Blush pink standards, maroon falls edged in pink.
Pale blue standards, purple falls.
Pure white standards, dark blue falls, orange beards.
Dark violet self.
Deep yellow standards, mahogany red falls.
Cream shading to orange-peach in centre.
Full, ruffled lilac self.
White self with pale yellow beards.
Leaves channelled, to 1 m long, 24 mm wide. Stem 80-140 cm tall. Flowers 1-3 in various combinations of white, blue, orange or yellow, 9.5-14 cm wide; spring. Falls with a claw 4-6 cm long, blade 4-5 long. Style branches 5-7 cm long, wider than claw.
A group of hybrids derived from I. tingitana and I. xiphium, with a lesser contribution from I. latifolia.
Most of the older cultivars carry the Iris mild mosaic virus (IMMV)
In Australia Edward (Ted) Armstrong of Red Hill Victoria, who died in 1985, was an outstanding breeder and had 7 cultivars registered with the Bulbous Iris Registrar in Holland.These were:'Blue Haze','Gwen Donnell','Marina','Mary Armstrong','Pastel Princess','Silver Dale' and 'Viscount'. Of these, 2 remain:'Marina' which is flax blue with a small orange signal, and 'Viscount' which has pale blue standards and rich deep violet blue falls with an orange blaze.
Bluish white standards, pale yellow falls with golden signals.
Orange-bronze to brown.
Blue standards, white falls with yellow signal.
White self with yellow signals.
Pale sky blue self with yellow signal.
Golden yellow self, very symmetrical with straight standards.
Pale lavender self.
Dark royal blue, small yellow signals.
Violet, large yellow signals edged in blue.
Royal blue standards, very pale blue falls with yellow signals.
Ivory white with yellow signals.
Violet standards, light blue falls, yellow signals.
Medium blue, golden signals.
Pure white self.
Cream-white standards, white falls with yellow signals.
Hybrids from many species including I. pumila, I. lutescens Lam. and I. reichenbachii. 10-40 cm tall, flowering earlier than the tall bearded iris including:
Dark burgundy standards, almost black falls, orange beards.
White, shading to lilac-blue edges.
Pink, with violet beards.
S love' Pale yellow with whitish patch on falls.
Cream-white shaded with yellow; deep blue beards.
Plants from 40 to 70 cm tall were produced by crossing cultivars from the dwarf bearded and tall bearded groups.
Pure black self.
Bright pink standards, apricot falls.
Light blue self with yellow beards.
Cream-white standards, yellow falls with orange beards.
Em up' Yellow standards, orange-red falls.
They are sturdy plants from swampy soils having stems with leafy spathes.The flowers are large and the capsules are 6 ribbed containing large, corky seeds. Louisiana hybrids were bred from i. brevicaulis Rafin., i. fulva Ker Gawl. and related species native to se usa, all semi-aquatic or growing in wet ground. Stems 40-180 cm tall, 2-6 branched and with leaf-like spathes. Flowers flat and open with all perianth segments broadly oval and spreading almost horizontally, in very diverse colour combinations. Signals are triangular and sometimes coalesce to form a star pattern in the centre of the flower. Late spring, with the remontants flowering again in autumn. Capsules 6 ribbed.
These are members of the series Hexagonae of the subgenus Limniris.
Caillet &Merzweiller (1988).
Modern hybrids have been developed in the USA and also in Australia and New Zealand in the last 50 years.
Flowers buff flushed with pink and yellow.
Rich cornflower blue self.
Finely ruffled lobes, white, shading to pale lemon in centre.
Sulphur-yellow self, remontant.
Bred in New Zealand by Sam Rix of Mt Maunganui in the North Island received the highest award for Louisianas in the usa in 1963. Successful breeders in Australia include Bob Raabe, John Taylor, Graeme Grosvenor, Heather and Bernard Pryor, Janet Hutchinson, Dr t.j. Betts and Peter Jackson. Goals include orange, red or near black segments, or segments with interesting patterns, also miniature forms.
S dream' Very broad overlapping maroon-red lobes, yellow star centre and edges.
Deep yellow self with broad ruffled lobes.
Very broad overlapping purple lobes, yellow-green star centre with pink styles.
Flowers pale blue with white centre and white edges.