Yellow iris Iris pseudacorus

Status Green - Least concern
Best Time to See May, June, July
Colour Yellow
Habitat Woodland

In a vase of gold And scarlet, how cold The flicker of wrinkled grays In this iris-sheaf! - 'Michael Field', 'Irises'

Also known as 'yellow flag'.

A tall plant (it can grow up to a meter and a half in height) with branched stems and large, bright yellow flowers. Its leaves are long and sword-shaped. It grows from a thick rhizome at the base. This give a black dye and black ink.

The yellow iris was chosen as the County Flower of Wigtownshire and the county's marshy hollows are often flooded with its bright 'flags' . It is known locally as 'segg' or 'sword-grass', a reference to the equally remarkable blade-like leaves.


Widespread throughout the UK, except for the Scottish Highlands.


A plant of damp places, from lake, ponds and river margins to wet woodland, fens, ditches and marshes.

Best time to see

When it flowers from May to July.

Did you know?

The yellow iris is thought by some to be the original 'fleur-de-lis' - a common symbol of heraldry.

It is apotropaic, i.e. believed to avert evil. Thus it was hung in bunches outside the doors on the Feast of Corpus Christi in Ireland.

Medicinally used for its astringency, to stop blood flow. Also the roasted seeds have been used to make an coffee-like drink.