Blue Iris Iris spuria Play pronunciation

Blue Iris (also commonly known as Salt Marsh Iris or Butterfly Iris) is a 5-foot tall, beardless, herbaceous perennial bulb native to Europe, Africa, and Asia. It is one of the tallest of the iris family. The genus is named for the Greek goddess of the rainbow and the epithet, Spuria, means false.

Blue Iris grows best in rich, well-composted, medium moisture, neutral to slightly alkaline, well-drained soils. For best flowering and disease resistance, site the plant in full sun, although it will tolerate light shade. Provide consistent moisture during growth periods, but avoid wet soils.  Amend heavy clay soils and avoid overhead watering. Raised plantings are another solution. Deadhead individual spent flowers and remove flowering stems to the ground after bloom. Divide plants immediately after flowering when overcrowding occurs.

It typically grows in clumps with attractive 4-foot-long leaves and flowers that display a range of colors from bluish-purple, white, blue, purple, wine and brown.

Use blue iris in borders or mass planted in butterfly or cutting gardens.

Diseases, Insect Pests, and Other Plant Problems: Good soil drainage is essential to combat potential soft rot problems. Insect problems include iris borer, iris weevil, slugs, snails, thrips, whiteflies and verbena bud moth. Major disease problems include bacterial soft rot, crown rot fungus, rhizome rot, and fungal leaf spot. Watch for mottling of leaves and flowers which may indicate the presence of mosaic virus. Mustard seed fungus can be fatal. Good sanitation practices can often prevent problems.