Quality flowers are an additional asset. Siberian iris are characterized by refined, grass-like foliage that provide an attractive accent all summer. Slender flower stalks give rise to elegant, beardless flowers, with the standards normally much shorter in length than the larger falls. Plants grow 1 to 3 feet tall in dense compact clumps. The rhizones are small tough and fibrous, and plants root quite deeply.
Siberian iris are of easy culture, thriving in most soils in full sun or light shade.
They grow best, however, in fertile, moist soils. The range of colors, heights and bloom tissue is expanding steadily thanks to the efforts of hybridizers. Beds should be well prepared with organic matter as this iris will be a long-lived planting. Clumps eventually become matted and are best divided after 5 to 10 years. Divide in July or August and keep new transplants of this species fairly moist during root establishment.