Iris 'Flavescens'
Common Name: tall bearded iris 
Type: Herbaceous perennial
Family: Iridaceae
Zone: 3 to 9
Height: 2.00 to 3.00 feet
Spread: 3.00 to 4.00 feet
Bloom Time: May
Bloom Description: Yellow
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Flower: Showy, Fragrant, Good Cut


Grow in average, medium moisture, well-drained soils in full sun. Tolerates some part afternoon shade, particularly in hot summer climates. Best with consistent moisture from spring to 6 weeks after flowering ends. Some drought tolerance once established. Best performance occurs in light sandy soils with excellent drainage. With clay soils or in areas of high rainfall, plant rhizomes on slopes (growing end uphill) or in raised beds to promote good drainage and discourage the onset of rhizome rot. Plant rhizomes, depending on location, from late July through October (late July–early September in areas with cold winters or September-October in areas with mild winters). Plant rhizomes 12-20” apart. Plant each rhizome shallowly over a baseball-sized mound of soil with 1/3 of the rhizome above the soil and with the roots horizontally spread to support the plant. Growth comes from the leafy end of the rhizome. If overcrowding occurs over time, lift the clump in late summer (August) with a garden fork, divide and replant. Keep the iris bed free of weeds.

Noteworthy Characteristics

Tall Bearded Iris is a rhizomatous iris class whose numerous hybrid cultivars grow to heights above 27.5” tall featuring two or more branches and 7 or more blossoms per stem with flowers spreading to more than 5” wide. Each flower has upright standards and pendant falls. Flowers bloom in June (St. Louis). Most cultivars produce plants significantly taller than 27.5”, with many rising to 38-40” tall. Bearded name comes from the bushy beard which is easily visible in the middle of each fall. Plants typically form clumps in the garden over time. Flowers bloom in an almost unlimited variety of different colors and color combinations. Narrow, linear green leaves are substantially erect.

Genus named for the Greek goddess of the rainbow.

'Flavescens' is an heirloom cultivar of uncertain origin first introduced in 1813. It is believed to be a naturally occurring hybrid, and naturalized populations can now be found growing along roadsides and in old residential properties and cemeteries throughout the eastern half of the United States. The fragrant blooms are a light lemon-yellow in color, and are held above dense, sword-like foliage on sturdy stalks up to 3' tall. An excellent selection for cutting.


Leaf spot, root rot, bacterial soft rot, crown rot and mosaic viruses may appear. Watch for slug, snails, whiteflies, aphids and thrips. Iris borers can cause significant problems in areas where they are found.

The major insect pest of bearded iris is iris borer. Major disease problems are bacterial soft rot and fungal leaf spot. Good sanitation practices are the most important component of any disease/insect control program: promptly remove and destroy diseased foliage/rhizomes, promptly remove and destroy borer-infected foliage/rhizomes and perform an annual clean-up of all debris and foliage from beds in fall after frost. The most frequent causes of failure to flower or sparse flowering are (1) rhizomes are planted too deep, (2) plants are located in too much shade, (3) plants were given too much fertilizer or (4) plants have become overcrowded and need division.


Best grouped or massed in sunny areas of perennial beds, borders or foundations.