Iris giganticaerulea

Last updated

Iris giganticaerulea
Blue Iris at Jean Lafitte Barataria Unit (cropped).jpg
Wild blue iris blooming in swamp at Barataria Preserve, Louisiana
Status TNC G3.svg
Vulnerable  (NatureServe)
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Iridaceae
Genus: Iris
Subgenus: Iris subg. Limniris
Section: Iris sect. Limniris
Series: Iris ser. Hexagonae
Species:
I. giganticaerulea
Binomial name
Iris giganticaerulea
Synonyms [1]
  • Iris aurilinea Alexander
  • Iris citricristataSmall
  • Iris elephantinaSmall
  • Iris fluviatilisSmall
  • Iris hexagona var. giganticaerulea(Small) R.C.Foster
  • Iris miraculosaSmall
  • Iris venulosaAlexander
  • Iris wherryanaSmall
  • Limniris giganticaerulea(Small) Rodion.

Iris giganticaerulea, the giant blue iris, is a species of iris, in the subgenus Limniris , in the series Hexagonae . It is a rhizomatous perennial, from northern America. It has long bright green leaves, very tall stems and one or two musky fragrant flowers in a range of blue shades (pale, bright, dark, lavender and violet) or rarely white.

Contents

Description

Iris giganticaerulea (the giant blue iris) is the largest species of the Louisiana irises. [2] [3]

It has very large green rhizomes, which are between 5 and 12 inches (13 – 30 cm) long and 0.75 to 1.5 inches (2–4 cm) thick. [4] [5] They are shallow rooted, marked with the scars (of the previous seasons) leaves, with many branches, which can form a large clump/colony growing up to 6 x 3 feet (182 x 91 cm). [5] [6] [2]

Rising from the plant's base are four to six bright green leaves, ensiform (sword-shaped) and between 20 and 30 inches (50–76 cm) long, 1.5 inches (4 cm) wide. [6] [7] [8]

It has very tall stems, that can grow between 28 and 71 inches (70–180 cm) tall. [4] [7] [9] They have two or three branches, [5] with one or two terminal flowers rising above the leaves. [2] [5] There may be up to twelve flowers on the plant. [8]

It blooms from early to mid spring, in the UK and America, [3] [5] with musky flowers. [2] [6]

It comes in a range of blue shades, [3] from pale blue, [2] [4] [5] to lavender blue, [2] [3] [10] to bright blue, [6] [7] [10] to dark blue, [4] [9] [11] and to violet blue. [2] [4] [6] Occasionally there is a white form, [3] [4] [8] or yellowish white. [2]

The flowers are generally 5 to 6 inches (13 to 15 cm) across. [4] [6] [10] They have six petals, three outer sepals (called the falls), which are flaring (1.75 inch or 4 cm wide), arch downward and have a white or yellow or faint orange signal patch or ridge. [2] [4] [7] They also have three inner sepals (called the standards), which are slightly erect or upright and narrower than the falls. [2] [7] [8]

It has a 4–5 cm long perianth tube, blue-violet style 1.3–1.5 inch (3.5–4 cm long) and two-lobed stigmae. [5]

After flowering, it has bright green ellipsoid capsules 3–4 inches (7–10 cm) long by 1 inch (3 cm) wide, which are hexagonal in cross section and shaped like a D. [5] [12]

Genetics

As most irises are diploid, they have two sets of chromosomes. This fact can be used to identify hybrids and classification of groupings. [3] It has a chromosome count of 2n=44. [4] [5] [11] It has been counted several times 2n=44, Randolph 1934 (ex Randolph & Mitra in Bulletin of the American Iris Society 140, in 1956) 2n=44 Riley 1942, 2n=42, R C Foster 1937 (as Iris hexagona var. giganticaerulea) [13] and 2n=44, Randolph, 1966. [12]

Taxonomy

It has the common name of Giant blue iris, [7] [14] [15] or Giant blue flag. [4] [6] [9] Note, the blue flag is normally Iris virginica .

It was first published and described by Small (of the New York Botanical Garden, [10] ) in 'Addisonia' in 1929. [16]

In 1937, Foster thought that it was a variety of Iris hexagona and renamed it Iris hexagona var. giganticaerulea. [13] In 1966, Randolph re-assessed it and classified it as a separate species. [12] [17]

Between 1950 and 1990, a large argument was waged over the state flower of Louisiana. Then a compromise was reached whereby the Southern magnolia became the state flower and the giant blue iris the state wildflower. [18] [19] [17]

It was verified by United States Department of Agriculture and the Agricultural Research Service on 4 April 2003, and then updated on 2 December 2004. [20]

Distribution and habitat

It is native to northern America. [20]

Range

Iris giganticaerulea is native to Alabama, Louisiana, [2] [3] [4] (on the west edge of Mississippi River), eastern Texas, [2] [6] [10] and Mississippi in the United States. [5] [11]

This constricted range is due to limited hardiness of the species. [10]

It grows in shallow freshwater, within roadside ditches, clearings within swamps (including cypress swamps, [10] ), wet meadows and marshes. [5] [9] [2] It is tolerant of brackish water. [2] [4]

Cultivation

Giant Blue Iris Seeds Irgi 002 php.jpg
Giant Blue Iris Seeds

The Louisiana irises generally all have similar cultivation requirements, with minor differences. They need full sunlight or partial shade, moist, acidic soils (ph level of 6.5) with a high organic and high fertility content (or humus rich). [6] [21] [22]

For best flowering, moisture is essential during late autumn, winter and spring times (between October and May), when the plant starts to grow new leaves. [23] They can be given a light feed between autumn and spring, if needed. [21] [22]

Propagation is best carried out by division of the rhizomes. [23] [24] [25] Which is best carried out in early autumn or early spring, when the plants are dormant. The ground must be prepared pre-planting, with the addition of a generous amount of organic matter and the soils dug to about 6 inches deep (to allow for new root growth). Plants require dividing every 3–4 years to promote good flowering. They can combine with other plants but tend to 'move' to suitable positions. [6] [21] [22]

If using a fertilizer, sprinkle around the plant in late January or February, before the plant is in flower. [21] [22] [23]

New plantings need to be mulched to prevent sun-scalding. [21] [22] It is also recommended to be added to during winter. [6]

The iris seed is not hard to raise but a very slow process. [24] It can take many months to germinate (between 3 and 12 months) with a 50% germination average. [22] They then can take 3–5 years before reaching flowering stage. [24]

Seeds should be harvested from the plant after flowering but they must be from mature seed pods. They then should be stored in paper bags, as seed stored in glass containers often goes mouldy. [22]

Iris giganticaerulea and Iris hexagona are considered too tender for cultivation in the UK. [8] [26] Since it needs moist acid soils, with warm summers and milder winters. [26]

It is hardy to USDA Zone 7 to 11 (or 5 and 6 if protected during the winter). [4] [6]

It is often available at water garden centres. [4]

Hybrids

Iris giganticaerulea can easily hybridize with other Louisiana irises to create new variants.

Several American garden nurseries and plant breeders have created many Iris giganticaerulea cultivars including, 'Angel Wings', 'Atrocyanea', 'Barbara Elaine Taylor', 'Bayou Barataria', 'Bayou Boeuf', 'Bayou St John', 'Bette Lee', 'Billy Mac', 'Biloxi', 'Cameron White', 'China Blue', 'Citricristata', 'Citricristata Alba', 'Citriviola', 'Coteau Holmes', 'Creole Can-Can', 'Easter Surprise', 'Elephantina', 'Excitement', 'Florence Zacharie', 'Gentilly Road', 'Gheen's White', 'Giganticaerulea Alba', 'Giganticaerulea Royal', 'Gulf Mist', 'Her Highness', 'High Hat', 'Iberville', 'Isle Bonne', 'Joe Mac', 'Kildea', 'La Bahia ', 'Lafitte', 'La Premiere', 'Laughing Water', 'Lazy Day', 'Longfellow's Gabriel', 'Mandeville', 'Miraculosa', 'Paludicola', 'Ruth Holleyman', 'Silverblu ', 'Snow Flag', 'Snow Goose', 'Southern Accent','Spanish Fort', 'Trixie'. [12]

Other crosses include with Iris fulva to produce 'Iris × vinicolor' Small. [5]

Related Research Articles

<i>Iris xiphium</i> Species of flowering plant in the iris family Iridaceae

Iris xiphium, commonly known as the Spanish iris, is an iris native to Spain and Portugal. It has also been found in Corsica, South West France, southern Italy, Algeria and Tunisia. This species is also known as the small bulbous-rooted iris.

<i>Iris cristata</i> Species of flowering plant

Iris cristata is a species in the genus Iris, it is also in the subgenus of Limniris. It is a rhizomatous perennial plant, endemic to the eastern United States. It has pale lavender flowers with a white patch and orange or yellow crest. It is a close relative to Iris lacustris, the only other crested iris native to North America. It is cultivated as an ornamental plant in temperate regions.

<i>Iris confusa</i> Species of flowering plant

Iris confusa (; also known as the bamboo iris is a species of iris, it is also in the subgenus Limniris and in the section Lophiris. It is a rhizomatous perennial plant, native to Western China. It has flowers which range from white to a soft lavender or pale blue in colour, with orange-yellow crests and purple dots. The plant's broad, shiny leaves are attached to bamboo-like stems. It is cultivated as an ornamental plant in temperate regions.

<i>Iris tectorum</i> Species of flowering plant

Iris tectorum is a plant species in the genus Iris, it is also in the subgenus Limniris. It is a rhizomatous perennial. It is native of China, Korea and Burma, with lavender-blue, bluish-violet, purple-blue, blue-lilac or sky blue flowers. There is a white form as well. It is a compact plant and is cultivated as an ornamental plant in temperate regions of the world.

<span class="mw-page-title-main">Louisiana iris</span> Group of flowering plants

Louisiana iris is a taxonomic group of five iris species native to Louisiana and surrounding regions of the southeastern United States: Iris fulva, Iris hexagona, Iris brevicaulis, Iris giganticaerulea, and Iris nelsonii.

<i>Iris sanguinea</i> Species of flowering plant

Iris sanguinea is a rhizomatous flowering plant in the genus Iris and in the series Sibiricae. It is cultivated as an ornamental plant in temperate regions. It is one of the species considered a Japanese iris. It is from Asia, found between Russia, Mongolia, China, Japan and Korea. It has grey green leaves, an unbranched flowering stem and flowers in reddish-purple shades, from blue to blue-purple, red-violet, with a rare white variant.

<i>Iris variegata</i> Species of flowering plant

Iris variegata, commonly known as the Hungarian iris, is a plant species in the genus Iris, also in the subgenus Iris. It is a rhizomatous perennial from eastern Europe. It has dark green, ribbed leaves. The branched flowering stems can be as tall as the leaves, they can hold 2–3 flowers in summer. They are yellowish-white, with brown-purple veins on the drooping falls. It is very hardy and it is commonly cultivated as an ornamental plant in temperate regions. There are several cultivars.

<i>Iris planifolia</i> Species of flowering plant

Iris planifolia is a species of flowering plant in the subgenus Scorpiris of the genus Iris, family Iridaceae. This bulbous perennial from Southern Europe and North Africa has long, shiny green leaves, a short stem, and large scented flowers in various shades of blue.

<i>Iris setosa</i> Species of flowering plant

Iris setosa, the bristle-pointed iris, is a species of flowering plant in the genus Iris of the family Iridaceae, it belongs the subgenus Limniris and the series Tripetalae. It is a rhizomatous perennial from a wide range across the Arctic sea, including Alaska, Maine, Canada, Russia, northeastern Asia, China, Korea and southwards to Japan. The plant has tall branching stems, mid green leaves and violet, purple-blue, violet-blue, blue, to lavender flowers. There are also plants with pink and white flowers.

<i>Iris tridentata</i> Species of flowering plant

Iris tridentata is a species in the genus Iris, it is also in the subgenus Limniris and in the series Tripetalae. It is a rhizomatous perennial, from the Southeastern United States. It has a cord-like rhizome, bright green leaves, long stem and fragrant flowers in spring in shades of blue.

<i>Iris brevicaulis</i> Species of flowering plant

Iris brevicaulis is a species in the genus Iris, it is also in the subgenus Limniris and in the series Hexagonae. It is a rhizomatous perennial, from North America. It has bright green, glossy long leaves, a long zig-zagged stem and 3–6 flowers per stem, which are come in blue shades from violet-blue, to lavender, to purple-blue, to bright blue to blue, and pale blue.

<i>Iris fulva</i> Species of flowering plant

Iris fulva, also known as copper iris, is a species in the genus Iris, it is also in the subgenus Limniris and in the series Hexagonae. It is a rhizomatous perennial, endemic to the southern and central United States. It has copper-red to deep red flowers and bright green leaves.

<i>Iris hexagona</i> Species of flowering plant

Iris hexagona, commonly known as the Dixie iris, is a species in the genus Iris, it is also in the subgenus Limniris and in the series hexagonae. It is a rhizomatous perennial with long bright green leaves, long thin stem and has small groups of flowers in shades of blue, from violet, to bluish purple, to lavender. It flowers in springtime and is native to the southeastern and south-central US states.

Iris nelsonii is a species in the genus Iris, it is also in the subgenus Limniris and in the series hexagonae. It is a rhizomatous perennial, from northern America. It has long drooping, grass-like leaves, tall stems, 10 red-purple flowers.

<i>Iris savannarum</i> Species of flowering plant

Iris savannarum is a species in the genus Iris, it is also in the subgenus Limniris and in the series hexagonae. It is a rhizomatous perennial.

<i>Iris bulleyana</i> Species of flowering plant

Iris bulleyana is a species in the genus Iris, also the subgenus Limniris and in the series Sibiricae. It is a rhizomatous herbaceous perennial, from South west China, including Myanmar and Tibet. It has long thin green leaves,

<i>Iris typhifolia</i> Species of flowering plant

Iris typhifolia is a species in the genus Iris, also the subgenus Limniris and in the series Sibiricae. It is a rhizomatous herbaceous perennial, from China. It has slender, twisted leaves, deep green slender hollow stem and 2 violet-blue flowers. It is cultivated as an ornamental plant in temperate regions.

Iris heweri is a plant species in the genus Iris, it is also in the subgenus Iris and in the section Regelia. It is a rhizomatous perennial, from Afghanistan. It has tall, green curved leaves, tall slender stems and purple blue or violet-blue flowers, with white and purple or lilac beard. It is cultivated as an ornamental plant in temperate regions.

<i>Iris hoogiana</i> Species of flowering plant

Iris hoogiana is a plant species in the genus Iris, it is also in the subgenus Iris and in the section Regelia. It is a rhizomatous perennial, from the grassy mountainsides of Turkestan. It has long green leaves, which are slightly purple at the base, and a long slender flowering stem. The flowers are blue, ranging from sky-blue to lavender blue and blue purple. It has orange or yellow beards. It is cultivated as an ornamental plant in temperate regions.

<i>Iris scariosa</i> Species of plant

Iris scariosa is a plant species in the genus Iris, it is also in the subgenus Iris. It is a rhizomatous perennial, from the mountainsides of Russia, Kazakhstan, Mongolia and China. It has sword-like, or sickle shaped, blue green or grey-green leaves, a short flowering stem, 3 or 4 membranous or semi-transparent flower bud leaves, 2 violet, reddish violet, lilac, blue-purple, or blue flowers in late spring, with yellow or white beards. It is cultivated as an ornamental plant in temperate regions. It was merged with another similar iris in the region, and Iris glaucescens became a synonym of Iris scariosa, before being divided into two separate species again. Although some sources still call it the main species, despite a slight colour difference.

References

  1. ↑ "Iris giganticaerulea Small is an accepted name". theplantlist.org. 23 March 2013. Retrieved 27 November 2014.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 "Iris giganticaerulea". fs.fed.us. Retrieved 27 November 2014.
  3. 1 2 3 4 5 6 7 Austin, Claire (2005). Irises: A Gardener's Encyclopedia. Timber Press, Incorporated. ISBN   978-0881927306. OL   8176432M.
  4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Kramb, D. (20 September 2004). "Iris giganticaerulea". signa.org (Species Iris Group of North America). Retrieved 5 December 2014.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 "FNA Vol. 26 Page 394". efloras.org. Retrieved 28 November 2014.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 "Iris". rslandscapedesign.blogspot.co.uk. 13 February 2010. Retrieved 10 December 2014.
  7. 1 2 3 4 5 6 "Iris giganticaerulea". wildflower.org. Retrieved 28 November 2014.
  8. 1 2 3 4 5 Cassidy, George E.; Linnegar, Sidney (1987). Growing Irises (Revised ed.). Bromley: Christopher Helm. p. 146. ISBN   978-0-88192-089-5.
  9. 1 2 3 4 Brzuszek, Robert F. (21 August 2014). "Louisiana Iris in the Home Landscape". msucares.com. Retrieved 27 November 2014.
  10. 1 2 3 4 5 6 7 Dillard, Tom W. "FROM NEW ORLEANS TO NEW ZEALAND, History and Development of The Louisiana Irises". zydecoirises.com. Retrieved 28 November 2014.
  11. 1 2 3 "Iris summary" (PDF). pacificbulbsociety.org. 14 April 2014. Retrieved 28 November 2014.
  12. 1 2 3 4 Laurin, Terry (19 August 2014). "(SPEC) Iris giganticaerulea Small". wiki.irises.org. Retrieved 28 November 2014.
  13. 1 2 Riley, Herbert Parkes (December 1938). "A Character Analysis of Colonies of Iris Fulva, Iris Hexagona Var. Giganticaerulea and Natural Hybrids". American Journal of Botany. Botanical Society of America. 25 (10): 727–738. doi:10.2307/2436599. JSTOR   2436599.
  14. ↑ "Iris giganticaerulea". facstaff.hsc.unt.edu. Retrieved 28 November 2014.
  15. ↑ "PLANT CHECKLIST". americaswetlandresources.com. Retrieved 10 December 2014.
  16. ↑ "Iridaceae Iris giganticaerulea Small". ipni.org (International Plant Names Index). Retrieved 27 November 2014.
  17. 1 2 Mary A.Hood Ecotravel on the World's Rivers&pg=PA38 _vmOwmSh12YC , p. 38, at Google Books
  18. ↑ "Louisiana Laws: RS 49:154.1" . Retrieved 28 November 2014.
  19. ↑ "LOUISIANA LAGNIAPPE". sos.la.gov. 2014. Retrieved 1 December 2014.
  20. 1 2 "Iris giganticaerulea". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 5 August 2015.
  21. 1 2 3 4 5 Gill, Dan; Owings, Allen (1969). "Louisiana Iris" (PDF). Louisiana State University. Retrieved 7 December 2014.
  22. 1 2 3 4 5 6 7 Helen Nash Guide to Water Garden Plants ssKzSCtgyZ8C at Google Books
  23. 1 2 3 Neil G. Odenwald and James R. Turner Selection, and Use of Southern Plants: For Landscape Design&pg=PA316 S__s1QADDJoC , p. 316, at Google Books
  24. 1 2 3 Nick Romanowski Garden Plants & Animals: The Complete Guide for All Australia gQsVgaxl-9kC at Google Books
  25. ↑ Gill, Dan (9 August 2006). "Get It Growing: It's Time To Divide Louisiana Irises Get It Growing News". lsuagcenter.com. Archived from the original on 13 December 2014. Retrieved 8 December 2014.
  26. 1 2 Stebbings, Geoff (1997). The Gardener's Guide to Growing Irises . Newton Abbot: David and Charles. p.  18. ISBN   978-0715305393.

Sources

Commons-logo.svg Media related to Iris giganticaerulea at Wikimedia Commons Wikispecies-logo.svg Data related to Iris giganticaerulea at Wikispecies

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.