Yellow Iris

Description

Iris pseudacorus is a rhizomatous wetland iris valued for its vivid yellow flowers, sword-shaped grey-green leaves, and vigorous clump-forming habit. Kew lists it as an accepted species native from Europe to the Caucasus and from the Mediterranean region to Iran, while Missouri Botanical Garden describes it as a strong wetland plant that forms colonies along streams, ponds, and marshes. It grows best in full sun to partial shade in consistently moist to wet soils and performs especially well in shallow standing water up to about 30 cm deep. Mature plants usually reach around 90 to 150 cm in height, making them ideal for the back of a pond margin or as a structural accent in bog gardens and rain gardens. This species is attractive and easy to grow, but it spreads readily by rhizomes and self-seeding, so it is better suited to controlled pond plantings or larger naturalistic water gardens than to small unmanaged sites. Missouri Botanical Garden specifically notes that it can behave aggressively and is considered invasive in some parts of North America.