Saturday, November 24, 2012

Iris typhifolia Kitagawa
Siberian Iris have been gaining in popularity for decades. Garden Siberian Iris have been developed from two species, Iris sibirica and Iris sanguinea. A third species was known from a specimen discovered and collected in 1928.With flowers in three parts the race of garden Siberians now come from three species.

Its common name in the west is the Cattail-leaved iris, in China it is known as North Tombs Iris. Iris typhifolia is found in northeast China, Inner Mongolia and the southern border of Far East Russia. It has wide distribution along the Amur River valley.

It grows in ecological systems associated with water; wet meadows, permanent swamps, rivers, temporary streams, seasonal wet spots. These are surrounded by northern broadleaf and coniferous forests.
Iris typhifolia 'Caitlan's Smile

A delicate beauty
Iris typhifolia flourishes in continental climate extremes, winter temperatures below -20F, summer heat to 100F degrees. Rooted in glaciated soil types and watered by northern temperate rainfall cycles of seasonal spring rains followed by droughty summers.

Long inaccessible during the cold war it is now a contribution to our gardens from northern China. With the opening of trade in the early 80s seed was collected and distributed to Kew Gardens and iris experts in England. It first flowered in 1989, young plants often failed with moderate winter weather, bloom was arrested by late spring frosts. It was determined it preferred a later more northerly spring season due to its early bloom habit. Iris typhifolia blooms weeks earlier than its sister species.

In 1992 further material was distributed from plants and seeds collected by Dr. James Waddick, Powell University, Missouri and Professor Zhao Yu-tang of Northeast Normal University, China. Their collaboration resulted in the book Iris of China. Members of the American Iris Society who sponsored their expedition received seeds and propagated a wide variety of seedlings.

Leaves are narrow, upright and elegant, sometimes twisted. The stem base can be reddish, flower stems smooth and hollow, bracts mottled brown or with reddish spots. Species flowers are generally shades of violet- blue with no known color variations such as white found in its sister species. Variation is found in flower form since seed collection was done from a variety of native colonies. Bloom occurs in early spring, weeks before other Siberian iris species and cultivars.

Cultural requirements are similar to most garden Siberian iris; sunlight conditions are full sun to light shade, soil pH average to acidic and wet mesic soils. (Please review Siberian Iris culture sheet found in this blog site.) 

Propagation is by seed and division. Species plants from seed, hybrids by seed or division. Seeds which ripen from July to September will bloom in their second or third season.

Hybridizers have found that Iris typhifolia contributes early bloom, added hardiness, different foliage characteristics, repeat bloom and prominent signals. New hybrids have expanded the bloom season and added classic butterfly forms with some color variations in white and greater range in blue.

Iris typhifolia ‘Caitlin’s Smile’ is a selected species form with erect foliage and purple blue flowers. 'China Spring' is the first introduced Iris typhifolia hybrid; it’s a great harbinger of the coming flowering season. 'China White' is a typhifolia hybrid. 

Iris enthusiasts and gardeners should seek out Iris typhifolia for its novelty and as a companion plant in moist gardening conditions. Its flower form works well in natural gardens as an early spring accent with wet mesic ornamental grasses and perennials.

Seek specialty iris growers for purchase of Iris typhifolia and its hybrids. Seed can be purchased through the Species Iris Group of North America (SIGNA).

This delightful iris can add great delicate beauty to your spring garden.

China White

1 comment:

  1. This is the first I've seen MY Irises. They came with an old house I bought and everyone told me to transplant them from the North side of the house between a cement wall and cement driveway. People kept saying it's too cold, too wet, Irises won't grow there. Now I know why my cold damp bed works so well for it :)