Content Detail

When someone says “ground cover”, iris is not usually the plant that jumps to mind. Dwarf crested iris does make a good ground cover. It grows only 6 or 7 inches tall and forms a dense mat.

  • Family (English) Iris
  • Family (botanic) Iridaceae
  • Tree or plant type Ground cover, Perennial
  • Native locale Illinois, North America
  • Size range Small plant (6-12 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Moist, well-drained soil
  • Tolerances Alkaline soil, Dry sites
  • Season of interest early spring, mid spring
  • Flower color and fragrance Blue, Purple, White
  • Shape or form Upright
  • Growth rate Fast

Size and method of spreading:

Dwarf crested iris grows 3 to 6 inches high and is a colonizing ground cover. Colonizing ground covers produce underground stems that spread out horizontally and shallowly, produce roots, and then send up new shoots. These plants are strong growers and may have the potential to grow aggressively.

Native geographic location and habitat:

It is native to several eastern and southeastern U.S. states.

Leaf description:

Its leaves are narrow and strap-like, with entire margins. They arise from the base of the plant.

Flower description:

The flower is the typical iris flower, but smaller than other species. They are blue or violet and marked with white and yellow. Flowers are produced in early to mid-spring.

Fruit description:

The fruit is a capsule and not ornamentally important.

Plant care:

Best growth is in partial shade, but this plant can adapt to full sun as long as the water supply is adequate. Too much water can lead to rot of the rhizomes and decline of the plants. Excess fertilizing can promote growth of foliage at the expense of the flowers.

Pests, diseases, and tolerances:

Slugs and iris borers can be a problem. Soft rot and rhizome rot can occur, especially in wet sites. This perennial is resistant to deer.

Abbey’s Violet dwarf crested iris (Iris cristata ‘Abbey’s Violet’):  

This variety has darker violet-blue flowers.

Eco Bluebird dwarf crested iris (Iris cristata ‘Eco Bluebird’): 

The flowers are lavender-blue and the plant has a more vigorous growth.

White-flowered dwarf crested iris (Iris cristata ‘Alba’):

The flowers on this variety are white and marked with yellow.


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