This diminutive, azure-flowered native iris grows to only about six inches.  Although not a long bloomer, Iris cristata spreads readily and is perfect for the shady woodland garden where it is a most welcome sight in spring.  Native Crested Irises complement Helleborus (Lenten Roses), Firepinks, Epimediums, spring bulbs, Columbine,  and just about anything else I can think of.

The official name of Belamcanda chinensis, or Blackberry Lily, has changed.  It is now officially Iris domestica but, not to worry, everything else is the same.  It still grows from two
to three feet tall and delights everyone who sees it with its orange, freckled flowers.  But it's not over after the blooms disappear: shiny black seed
clusters resembling blackberries are equally interesting and attractive in arrangements.  Iris domestica can withstand heat, sun, and dry soil and is sure to please.  Zones 5-9.  Quarts.

Partial to moist, acidic soil, these stunning Japanese Water Irises are perfect at water's edge where they will
thrive and increase in size and beauty with each passing year.  Iris ensata grows from three to four feet tall in full
sun.  This photo was taken of Iris ensata growing on a hillside
(courtesy of the birds) in partial shade where it is equally at home.  Zones 5-8.

Iris foetidissima is sometimes called "Stinking" Iris and  "Roast Beef Plant" because of the beef-like odor that some say emanates from the crushed or bruised leaves.  Native to the open woodlands of Europe and Britain, Iris foetidissima has beautiful sword-like foliage and steel blue flowers, although the somewhat drab blooms are not the attraction.  The real display comes later with seed capsules and scarlet berries that offer much needed winter interest  - that is, unless you want to use them in dried arrangements (see photo below).  Iris foetidissima grows from one to two feet tall, with a spread
of two feet, in bright shade. Something good to know:  it is the only iris that is said to thrive and bloom in  deep shade, and it is said to be evergreen in Zones 7 and above.  Zones  6-9  Quarts.  (These lovely photos are by Jymm of France and were generously donated to the public domain via Wiki Commons.)  Temporarily  unavailable.

Iris fulva, a native Louisiana iris, occurs from southern Illinois and southeast Missouri and Kentucky, south to Louisiana and east to Georgia in swamps and wet meadows.  Growing to about two feet tall, Iris fulva is also known as "Copper Iris" because of the copper red to brick red and, occasionally, yellow blooms in late spring.  Iris fulva has bright green leaves and will form large clumps if given a site with adequate moisture.  Copper Iris has an understated beauty that I very much admire.  Sun in Zones 5-10.

With a name like Iris prismatica, you know this native iris has to be beautiful. (Iris was the Greek goddess of the rainbow, and "prismatica" means prism-like.) Native to bogs and marshes from Maine to Georgia, Iris prismatica grows from one to three feet tall with blue to purple flowers and grass-like leaves and will make a sizable clump given time. Hummingbirds like it, and so will you. Sun. Zones 4-8.  (Photo from Wiki Commons and in the public domain)

Iris pseudacorus, or Yellow Flag Iris, likes moisture, but it will also thrive in ordinary soil.  In moisture-retentive soils, Yellow Flag will grow to over five
feet tall and spread rapidly.  In that setting, it is the idea water garden plant.  In ordinary soil, however, it is shorter and spreads far less; in fact, I have had the same clump for more than 20 years in a garden spot with too much shade and too little water, and it doesn't seem to have moved a muscle.  The blooms of Yellow Flag Irises are a bright, pleasing yellow, and the green, sword-like foliage is imposing; a mass planting is a sight to see when in bloom. Gallons.  Sun.  Zones 4-9.

This beautiful species of Siberian Irises grows two to three feet tall, spreading rapidly in water, but it can also be grown out of water, in regular garden soil, where it will grow less aggressively.  These plants were grown from seeds labeled "Kamayama" purchasedat the annual SIGNA seed exchange a couple of years ago.  They should be this deep purple color and, frankly, I can't wait.  Zones 4-9.  (Photo by Quert1234, via Wiki Commons, and in the public domain)

Beach Flag, Beachhead Iris, Arctic Iris, Alaska Flag, Wild Dwarf Iris, Wild Flag Iris, and Hairy Iris ("setosa" means hairy) are just some of the common names for this deep violet, beardless native of Alaska, Iris setosa.  So, I ask you, if it doesn't have a "beard," then
why is it hairy?  Beats me.  I just know that Iris setosa is a beautiful iris
and one I'm pleased to be able to include in my plant list.  The blooms are
deeply veined in dark purple, the signals are yellow/white, and the stiff green
foliage is tinted purple at the base.  Iris setosa grows from 12-18 inches in full sun or bright shade, and since it's a native of Alaska, you can bet your bottom dollar that it is extremely cold hardy. It prefers moist, well-drained
soil and is more drought tolerant if planted in shade.  Zones 3-8. Quarts.

Of all the irises I have grown, Siberians are my favorite.  I like their wide array of colors, their almost regal grace, and their grass-like foliage.  Better than that, they can go almost forever without having to be divided, and they are drought tolerant and, despite their fragile appearance, are quite rugged.  These irises grow from two to three feet high in sun.  Zones 3-9.

Iris tectorum is the purple, or lavender, version of the spring-blooming Japanese Roof Iris.  Iris tectorum has the same endearing qualities and growing habit as white Japanese Roof Irises below.  I don't see how one could possibly go wrong with either.  Sun in Zones 4-9. (Photo by H. Zell, Wiki Commons.)

Iris tectorum "alba" is a beautiful white-blooming iris that I am particularly fond of.  The story goes that this white Japanese Roof Iris was found growing on rooftops in Japan, as it was decreed at that time that land could only be used  for food crops.  I don't know about rooftops, but on terra firma this perennial  grows to about 15 inches in spring, and
it likes its terra firma on the dry side.  Iris tectorum "alba" has a lovely spreading habit, which makes it most attractive to look at and very agreeable when it comes to dividing.   Sun.  Zones 4-9.

The name "flag" is from the middle English, flagge," which means "rush" or "reed, and that's why Iris versicolor, native to the swamps, marshes, and wetlands of the northeastern United States, is commonly known as "Blue Flag."  Blue Flag grows to about two feet with violet-blue flowers in late spring and prefers moist conditions and sun in Zones 3-9.  Quarts.  (Illustration from The Botanical Magazine, Vol. 1, by William Curtis, from Wiki Commons and in the public domain).

This beautiful native Blue Flag grows best in a bog or water garden, but it will also thrive in a moist garden.  Pale green, sword-like foliage and blue-violet blooms with yellow and white markings set atop 3-foot stems in late spring.  Zones 3-9, Sun, light shade.  (Illustration by M.S. del, J.N.Fitch, lith. [Public domain], via Wikimedia Commons)

The official name of Pardancanda is now Iris x norrisii, but everything else about it is just the same.  Whatever this cross between Belamcanda chinensis (now Iris domestica!) and Pardanthopsis dochotoma, is officially called, I'm just grateful for its common name:  Candy Lily.  I grew this Candy Lily from seed, and I was delighted with the interesting mix of colors, as well as  the size - none of that droopiness people complain about.  Candy Lily likes average, well-drained soil, and sun.  After the blooms are spent, try cutting it back for new plants to emerge, or let the seeds ripen to grow more.  Zones 5-9,  to three feet.  Quarts.