Yellow Flag - Iris pseudacorus
Irish name - Feileastram siolastrach
Iris family - Iridaceae
The Yellow Flag, also known as Yellow Iris, Yellow Flag Iris, Jacob’s Sword or Segg is native to the wetlands and marshes of Northern Ireland. It is also distributed throughout Europe, North Africa and the Mediterranean region. This Iris is a common plant across the British Isles, apart from the Scottish Highlands, but is the only wild Iris in Northern Ireland.
This easy to identify wild plant charms us with its bright, showy, yellow flowers, which bloom from May to July. As the plant can grow up to 1.5 m tall, these flowers can also reach a handsome size (80-100 mm across), hence its name. The leaves of the Yellow Flag Iris appear long and sword-shaped and may be as much as 25mm wide.
Once the flowers have been pollinated by insects, large (7-9mm), brownish seeds begin to develop inside a capsule. This capsule splits open to release the seeds.
In ideal conditions it can become invasive and form large and dense stands, which out compete other plants. On the other hand though, land drainage controls this plant.
This species grows quite happily on sunny or partly shaded sites and is known to help remove metals from the soil.
Propagation
By division
Plants are best propagated by the division of rhizomes and potted on or planted into their permanent positions (rich moist soil preferred). This can be done during spring and early summer.
The following grow in similar habitats (alphabetical by common name)
Permission from the landowner - and, if the site holds any kind of designation, from Northern Ireland Environment Agency too - must be sought before collecting plant material (including seeds).