Yellow flag iris perennial blub in the Iridaceae (iris) family native to Eurasia and Africa. The genus name Iris is named after the Greek Goddess of rainbows and the common name, "flag", comes from an old English word (flagge) for reeds and refers to its natural preference to wetlands. The showy yellow flowers appear in the spring and its bright green sword-shaped clumping foliage reaches up to 3 feet in height. These plants grow aggressively and spread quickly in wet soils including water up to 10 inches deep or the wet muds along a pond. Yellow flag iris spreads by rhizomes and seeds and can quickly overtake native plants in wet sites. Although it prefers full sun and boggy sites, it can adapt to somewhat drier sites in moist to wet gardens. While it is a popular perennial planted at the edge of ponds and waterways, the North Carolina Invasive Plant Council lists yellow flag iris as invasive . Invasive plants are especially threatening to wetland habitats due to their ease of spread through seeds and plantlets, and through their rapid growth. See native plant alternatives in the left-hand column. I nsects, Diseases, and Other Plant Problems: Listed as invasive by the NC Invasive Plant Council. It is also listed as invasive in Virginia and several other northeastern states as well as several northwestern states.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.