Grow Wild to Know Wild
Yellow Flag Iris(Iris pseudacorus)

Flowers: June to August
Preferred site: Sunny

Description: A tall plant (up to 1.5m) with branched stems and large, bright yellow flowers (80-100mm across). Leaves are long and sword-shaped.

©Joe Sutton

Habitats in the wild: A plant of damp places, from lake and river margins to wet woodland and marshes.

Conservation status and threats: Yellow Flag Iris is a common and widespread native plant in Britain. Its distribution has remained relatively stable since the 1960s, so is not considered to be a threatened species.

Reasons for losses in the wild : Drainage of wet habitats and over-competition from excess nutrient pollution.

Folklore/medicinal uses : Yellow Flag Iris, also known as Jacob's Sword and Segg, is a symbol of spring from our wetlands. It is sometimes suggested as the origin of the fleur-de-lis in heraldry. A local name, Segg, comes from the Anglo-Saxon for a short sword, referring to the blade-like character of the leaves (Flora Britannica by Richard Mabey).

A slice of the root held against an aching tooth is said to bring immediate relief (http://www.pfaf.org).

Position in garden : An easy and vigorous plant for the pond margin, bog garden, or a constantly moist border. They appreciate a rich, well-dug soil, but can be somewhat invasive under optimum conditions.

How to plant and when: Plant bare-rooted or potted plants during the spring or early summer months, into well-prepared fertile garden soil.

Propagation: Yellow Flag Iris is most easily propagated by division of the rhizomes, and potted on, or planted in their final position in the garden.

Varieties available: The variety 'Alba' has pale creamy flowers, while 'Flore pleno' has double yellow flowers, although neither is widely available.

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