With more than 300 iris species and thousands of cultivars, you shouldn't have trouble finding the types of iris that thrive in your garden environment. The word "iris" comes from the Greek word for "rainbow"—an apt term for a genus of flowers that offers such a wide range of color combinations, flower sizes, and shapes.
Gardeners value irises for their reliable spring performance and hardy vigor in the landscape. even in hot and dry conditions. The lifespan of irises ranges between five and 20 years depending on the variety. The iris is also a beautiful bloom to incorporate into your cut flower arrangements.
Here are nine iris types popular for North American gardens.
- 01 of 09
Bearded Iris
There are more than 60,000 cultivars of bearded iris, virtually all are cultivars of Iris germanica. Planting different varieties lets you create a landscape with any color scheme you desire, and, if you add some reblooming irises, you'll enjoy a color show all season. The American Iris Society groups bearded iris into several subdivisions, including the tall bearded (higher than 27.5 inches) and intermediate bearded (16–27 inches).
- Name: Bearded iris (Iris x germanica)
- Native Area: Southern Europe and the Mediterranean
- USDA Hardiness Zones: 3–9
- Flower Colors: Red, orange, yellow, blue, purple, brown, white, pink, bicolors
- Height: 2–3 feet
- Sun Exposure: Full sun
- Soil: Well-drained
- 02 of 09
Dwarf Bearded Iris
The dwarf bearded iris group includes those cultivars of I. germanica that grow 8–15 inches high. Another subdivision, the miniature dwarfs, grows less than 8 inches high. What's not to love about these little powerhouses that illuminate your border garden and rock garden? Dwarf bearded iris varieties multiply quickly and let you populate an area of your yard with an investment of just a few plants. Some growers think these irises tolerate shade better than their standard cousins.
- Name: Bearded iris (Iris x germanica)
- Native Area: Hybrid, no native range
- USDA Hardiness Zones: 3–9
- Flower Colors: Orange, yellow, blue, purple, white, pink
- Height: 2–3 feet
- Sun Exposure: Full sun; tolerates partial shade
- Soil: Well-drained
- 03 of 09
Dwarf Crested Iris
The native dwarf crested iris has a special appeal to woodland gardeners, as it grows best in part shade. The 6-inch-high flowers appear from March to May and will attract hummingbirds and bees to the garden. Provide acidic soil to mirror the conditions of the pine groves where these plants grow in the wild. Like the bearded iris, this species spreads through rhizomes that can be divided to propagate new plants.
- Name: Dwarf crested iris (Iris crestata)
- Native Area: Eastern United States
- USDA Hardiness Zones: 3–9
- Flower Color: Blue, yellow, pink, purple, white
- Height: 6–9 inches
- Sun Exposure: Partial shade; tolerates full sun
- Soil: Well-drained
- 04 of 09
Species Irises
The Iris genus contains hundreds of species, many of which are endemic to small geographic regions and therefore not often cultivated. You may encounter these lesser-known varieties through small specialty nurseries or online plant forums where iris collectors propagate colonies of unique irises. Don't collect wild irises, which may be endangered in their native habitats. If you struggle to grow plants in an area with wet spring soils following the winter thaw, try I. missouriensis. Gardeners in the South should try I. confusa, also known as the bamboo iris, which prefers frost-free climates and growing conditions similar to azaleas.
- Name: Iris (Iris spp.)
- Native Area: North America
- USDA Hardiness Zones: Varies by species
- Flower Colors: Varies by species
- Height: Varies by species
- Sun Exposure: Varies by species; most prefer sun
- Soil: Varies by species
Continue to 5 of 9 below - 05 of 09
Dutch Iris
Dutch irises were developed in the Netherlands from parent species native to Spain and Morocco. Gardeners often overlook the small, simple flowers of Dutch irises, like the 'Apollo' cultivar, but these diminutive varieties serve as good companion plants. Try growing them among early salad greens, which will obscure the fading foliage of the iris after they finish blooming. Rather than growing from rhizomes, these are bulbous irises. Plant the bulbs deeply in the fall.
- Name: Dutch iris (Iris hollandica)
- Native Area: Hybrid, no native range
- USDA Hardiness Zones: 6–9
- Flower Colors: Yellow, blue, white
- Height: 18–24 inches
- Sun Exposure: Full sun
- Soil: Well-drained
- 06 of 09
Japanese Iris
The Japanese iris isn't as well known as the bearded iris or Dutch iris, but gardeners who want large blooms should seek them out. Some varieties, like 'Amethyst's Sister' and 'Freckled Peacock,' routinely exceed four feet in height. The Japanese iris demands constant moisture, full sunlight, and rich soil, so these plants would make a good addition to a pond- or stream-side garden where the soil stays wet.
- Name: Japanese Iris (Iris ensata)
- Native Area: Eastern Asia, Kazakhstan
- USDA Hardiness Zones: 4–9
- Flower Colors: Blue, lavender, pink, white
- Height: 2–4 feet
- Sun Exposure: Full sun to partial shade
- Soil: Loamy, clay, acidic
- 07 of 09
Siberian Iris
Siberian irises, a beardless subgroup of irises, are hybrids, derived mostly from two blue-flowered Asian species, I. sibirica and I. sanguinea. They bloom slightly later than the bearded iris, providing a color bridge to summer perennials. Unlike bearded iris, whose foliage becomes ratty and ugly after the plants finish blooming, Siberian iris maintains its elegant waving foliage through the season, resembling an ornamental grass. Siberian iris is fairly drought tolerant and may succumb to crown rot if the soil is too wet.
- Name: Siberian iris (Iris sibirica)
- Native Area: Hybrid, no native range
- USDA Hardiness Zones: 3–8
- Flower Colors: Blue, violet, purple
- Height: 3–4 feet
- Sun Exposure: Full sun to partial shade
- Soil: Moist, well-drained
- 08 of 09
Yellow Flag Iris
This vibrant and vigorous iris comes with a caveat, it is considered invasive in many parts of the United States, so gardeners should cultivate the yellow flag iris responsibly and prevent it from escaping into nearby lakes and wild areas. This iris type spreads aggressively by rhizomes and may be best controlled in a container garden.
- Name: Yellow flag iris (Iris pseudacorus)
- Native Area: Europe to western Siberia; Caucasus; northern Africa
- USDA Hardiness Zones: 5–9
- Flower Color: Yellow
- Height: 3–5 feet
- Sun Exposure: Full sun to partial shade
- Soil: Moist, loamy, clay
Continue to 9 of 9 below - 09 of 09
Louisiana Iris
The name Louisiana iris refers to several beardless hybrids derived from five native species: I. fulva, I. hexagona, I. brevicaulis, I. giganticaerulea, and I. nelsonii. They are not the result of nursery development but naturally occurring in the native boggy, swampy habitats in the Gulf Coast area. These water-loving irises prefer mild temperatures, moist spring weather, and slightly acidic, sandy soil found in that area. Some varieties are hardy as far north as Zone 4.
- Name: Louisiana iris (Iris x)
- Native Area: Lower Midwest and southern United States
- USDA Hardiness Zones: Varies by type
- Flower Colors: Blue, purple, white, bicolor
- Height: 12–60 inches (varies by hybrid)
- Sun Exposure: Full sun to partial shade
- Soil: Moist, acidic
The American Iris Society also includes several other divisions and subdivisions of irises in addition to the ones described here. As you develop your enthusiasm for irises, you may want to explore some of the more exotic and unique classifications.
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Are all irises perennials?
With over 300 species available, the iris family are perennials and that come back every year.
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How do you care for iris flowers?
Irises should be given plenty of water, and most do best in full sun (meaning six to eight hours per day). Once the blooms are finished, you should deadhead them.
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Do irises attract butterflies?
The iris flower is not only beautiful, but they attract butterflies and hummingbirds, too.