By EMGVs Jackie MacLeod and Cy Gurney
Cy Gurney and I became friends and Extension master gardener volunteers at the same time, so perhaps it’s no surprised that we share a love for growing irises. Our two Durham gardens present different growing conditions. My garden is a sunny downtown location. Cy’s garden, in the northern part of the county, is shaded by mature canopy trees. Yet we both are able to enjoy growing iris, an ornamental plant that commands attention at spring time with their regal stature, big blasts of color and, as with some varieties, that gentle scent of a freshly opened bottle of cream soda.
The name iris comes from the Greek word for rainbow–a reference to the vast amount of colors that irises display. They are easy to grow in zones 3 to 8 in the East. They prefer a sunny site and a light, loamy soil with pH of 6 to 7. They don’t like their rhizomes wet, so amend your clay soil with organic matter to improve drainage. Also, bury the rhizome firmly in the soil but near the surface; if planted too deeply, an iris will not bloom. Plant them in July, August or September and they will reward you the following year.
Iris in Jackie’s Sunny Garden
An iris flower has three upright petals called “standards” and three hanging petals called “falls.”
Some irises have fuzzy growth at the beginning (central side) of each fall. That is called a beard and those irises are Bearded Iris or Iris Germanica. The beard can be in contrasting colors to the petal (fall) below and is assumed to help attract pollinators.
Below is a picture of a Bearded Iris very similar to ‘Madame Henry Cayeaux.’ The light pink colored petals are the standards, the deep purple falls have a lighter color variegation towards the center and, laying on top of it, you can see the fuzzy yellow beard.
Here is another Bearded Iris. You can see the yellow beard laying on the striated yellow-gold and purple fall. If you compare the petals to the bearded iris in the picture above, you will see that these petals are ruffled. I believe this iris is called ’Nibelungen.’
Here is a variegated purple and white Bearded Iris. The flower shape and beard are much harder to discern in this variety ‘Batik,’ (see photos below) which is German for tie-dye. It’s quite the show-stopper!
Iris in Cy’s Shadier Garden
Irises have long been a favorite for many gardeners, yet not all gardens have the full sun needed for the large and beautiful bearded irises. If your tree canopy is tall and not dense, in the spring you can try these types of irises in your part-shade garden. These were in full bloom in April in my shady garden in northern Durham.
Iris japonica ‘Eco Easter’ is also known as Fringed Iris and Butterfly Flower. This is an easy to grow plant. It spreads 12 to 15 inches and grows in dense clumps of broad fans of green strap shaped leaves. It is an evergreen herbaceous perennial. It has two-inch lavender-blue flowers that have a yellow base and with darker purple markings on the lower petals (the falls) with the inner lavender-blue petals (the standards) that are narrow with fringed tips. The buds flower on multiple stems, which bloom reliably and in secession during early to mid-spring. It thrives in part-shade to full-shade and is deer resistant. It spreads by long slender, creeping rhizomes, making this an easy plant to share.
Iris hollandica ‘Dutch Iris’ (pictured below) grows from a teardrop shaped bulb. The flower colors are pale blue, lemon-yellow and deep purple, bronze, rose and gold. These are popular because they are long-lasting and look great in a flower vase. They have tall 18- to 24-inch sturdy stems which look nice in the back of a spring garden. The bulbs were planted in the fall among daffodils and tulips. They can rebloom a second year, but most gardeners treat them as annuals and replant new bulbs each year. They perform best in sun but they will also grow in part-shade.
Iris tectorum ‘Roof Iris’ is a herbaceous perennial. This is a 15-inch tall species of the crested iris group with large, six -inch across, beardless, bright lilac-purple flowers which are crested white. The leaves are in fans of narrow, lance-shaped leaves that are supple and arc in a lovely display. The rhizomes should be spaced 16 inches apart as this plant can spread vigorously, so plant with a plan in mind. It is deer resistant and does not require a great deal of water. It does well in sun and part-shade gardens. The common name is derived from the historical use on thatched roofs in its native China and Japan.
Sources & Further Reading
Planting and growing irises
NC Extension Plant Toolbox
Missouri Botanical Garden Plant Finder